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Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-13T00:06:04Z

MaxForman: /* Government Response and Recovery Efforts */

= Environmental and Social Impacts of the 2021 Flooding Season in Southern BC =
== Introduction ==
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]From November 13 to 15th 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
== History of the Sumas Prairie and its Colonization ==
The Sumas prairie has experienced extreme change to appear the way that it does today. Historically, the eastern part of the Sumas Prairie was occupied by Sumas Lake, before its eventual draining for agricultural purposes between 1920 and 1924. Farmers sought the fertile soil at the bottom of the lake<ref>{{Cite web|date=January 7, 2025|title=Sumas River and Canal|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects/sumas-river-and-canal|url-status=live|website=Government of British Columbia}}</ref>.

Historically, Sumas Lake saw much natural variability, which mainly was caused by the Lake's connection to the Fraser River, which is in turn connected to the Pacific Ocean. The water levels of the Fraser River typically rise in the summer due to snowmelt. This unpredictability in the Fraser directly translated to the Sumas Lake, with the water levels of the Lake seeing large changes in depth and size depending on the season, snowmelt, and even the Pacific tides<ref name=":7">{{Cite journal|last=Murton|first=James|date=January 2008|title=Creating Order: the Liberals, the Landowners, and the Draining of Sumas Lake, British Columbia|url=https://www.proquest.com/docview/216123962/fulltextPDF/D6152C190D6F41EBPQ/1?accountid=14656&sourcetype=Scholarly%20Journals|journal=Environmental History|via=ProQuest}}</ref>.

The Stó:lō people are an Indigenous group that have historically inhabited the Fraser Valley for at least 4,000 years. They had a deep connection to Sumas Lake, both for cultural purposes and for fishing. In 1858, the discovery of gold in the Fraser Valley meant that the Stó:lō were forced into reserves by James Douglas, British Columbia's governor<ref name=":7" />. In the 1970s, there began to be discussion and legislation surrounding diking the Sumas Lake. By 1920, the conversation had shifted towards draining the lake, with hopes of accessing the fertile soil at the bottom of the Sumas Lake and avoiding its unpredictable shifts. By June 26, 1924, the Sumas Lake was gone<ref name=":7" />. Today, the lake remains drained and is mostly covered by agricultural lands.

==Converging Factors and Causes of Flooding==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

In addition to the unprecedented atmospheric river, the Sumas lake was a contributing factor to the severity of flooding. Between the Sumas Mountain and Vedder Mountain in the Lower Fraser Valley, the Sumas lake was historically the center of a dynamic floodplain landscape<ref name=":4" />. The Indigenous food system in the area was supported by a high amount of animal and plant life<ref name=":4" />. In addition to its biodiversity, the lake could vary from an area of 9,000 acres (3,642 ha) and a depth of 3 meters in the winter, to an area of 26,000 acres (10,522 ha) and depth of 11 meters in the spring<ref name=":4" />. During the past 150 years, the Lower Fraser has seen changes within its vast network of rivers, creeks, wetlands, and floodplains. These ecosystems have been developed into a series of ditches, canals, dikes, floodgates, and agricultural fields, in an effort to further residential and urban development in the area<ref name=":4" />. The changes in the lake's historical wide array of seasonal depth and the progression of urban development resulted in 30% of native vegetation remaining intact and over 85% of floodplain habitat and 64% of streams being lost<ref name=":4" />. In the early 1920's, The Sumas Lake was drained after an act in a Canada-wide process of land dispossession from Indigenous peoples in Canada<ref name=":4" />. The loss of traditional use and knowledge resulted in mismanagement practices that increased the flood risk in the area. By the mid 1920's, a plan was put in motion to drain the lake in order to further expand agricultural practices in the area. By 1924, the Chilliwack River had been diverted west, draining the lake through the Sumas Drainage Canal and into the Fraser River around the northeastern tip of the Sumas Mountain<ref name=":4" />. Despite the loss of the lake, the low elevation remained, resulting in permanent flood risk for the newly developed agricultural area.

==Impacts ==
The flooding caused by the 2021 atmospheric river had severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, caused severe damage to both the environment and infastucture in surrounding areas, in addition to public safety and human health risks.

=== Human Impacts ===

During the floods and the resulting landslides, five individuals were confirmed dead, with well over 3,000 residents forced out of their homes and evacuated in the Abbotsford area alone <ref name=":4">{{Cite web|last=Finn et al.|date=02 June 2024|title=Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake|url=https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2024.1380083/full|url-status=live|access-date=08 March 2026}}</ref>. In the Sumas Prairie, the former Sumas Lake refilled, displacing thousands and destroying homes built on the historic lake bed<ref name=":4" />. Farms, homes, businesses, and transportation corridors flooded, causing destruction to livelihoods and infrastructure. Many of those affected by the flooding, were not aware that their homes and farms were located on a former lakebed—Sumas Lake.

Floodwaters transported significant amounts of debris, sediment, and bacteria. E. coli counts at several locations, such as the Pitt Meadows Shoreline, exceeded Canadian Drinking Water Quality Guidelines (CDWQG) following sanitary sewer overflows <ref name=":5">{{Cite web|last=Minton et al.|date=June 2022|title=Water Quality Assessment of the Fraser River Following
the November 2021 Floods|url=https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/flood-response-and-the-environment/water-quality/water_quality_assessment_of_fraser_river_2021_floods.pdf|url-status=live|access-date=09 March 2026}}</ref>. Sanitary sewer overflows (SSOs) and the overflow of septic systems led to dangerous spikes in bacteria and other waterborne pathogens which pose risks to human health <ref name=":5" />.

Due to the flooding, many were forced to stay home and not travel within the flooded region for extended periods of time. For many days during November of 2021, using smartphone tracking data, it was found that there was virtually no travel between the cities of Hope, Merritt, and Chilliwack (all three are within the Fraser Valley and were affected by the floods)<ref>{{Cite journal|last=Liao|first=Enqi|date=May 24, 2024|title=Travel Behavior during the 2021 British Columbia Floods Using De-identified Network Mobility Data|url=doi.org/10.32866/001c.117422|journal=Resilience Findings}}</ref>. In the following weeks, travel between the cities slowly began to increase, but it took extended time for typical travel between the cities to return.
=== Environmental Impacts ===

The floods severely degraded the Lower Fraser Valley's critical habitat, which is essential for Pacific salmon and sturgeon. Rapidly rising waters caused massive sediment movement which buried salmon spawning grounds and destroyed eggs. Scientists note that the full impact on salmon populations may not be known until their 2 to 5 year life cycles are complete in spawning season of 2026 <ref>{{Cite web|last=DFO|date=2022|title=Extreme environmental impacts on Pacific salmon|url=https://www.pac.dfo-mpo.gc.ca/pacific-smon-pacifique/environmental-impacts-environnementaux-eng.html|url-status=live|access-date=09 March 2026}}</ref>.

Excessive nutrients (nitrogen and phosphorus) washed into slow moving bodies of water from farmland, leading to eutrophication. Eutrophication occurs when nutrient runoff (often from agricultural fertilizers) causes rapid algal growth. When the algae dies, the bacteria that decompose the algae consume dissolved oxygen, creating hypoxic (not enough oxygen) conditions. These hypoxic conditions can suffocate aquatic organisms <ref>{{Cite web|last=Ross et al.|date=November 2022|title=A lake re-emerges: Analysis of contaminants in the Semá:th X̱ó:tsa (Sumas Lake) region following the BC floods of 2021|url=https://www.raincoast.org/reports/flood/|url-status=live|access-date=09 March 2026}}</ref>.

The death of over 670,000 farm animals created a biological hazard through an increase of immediate groundwater contamination and the spread of disease <ref name=":6">{{Cite web|last=Province of British Columbia|date=2024|title=Flood debris management projects|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects|url-status=live|access-date=09 March 2026}}</ref>. Crews eventually removed over 16,000 metric tons of natural and man-made debris (including 98 vehicles and 4 bridges) from provincial waterways to prevent further ecological blockages from occurring as a result of the floods <ref name=":6" />.

The flooding not only contributed to land destruction, but had severe impacts on rivers and natural water systems. The unprecidented rainfall contributed to the destabilization of slopes, erosion on shorelines, and damage to critical infasturcture such as dikes and highways. Extensive human made debris was dispersed across multiple waterway systems. Among the debris, entire homes and buildings were washed into river streams, along with vehicles, propane and fuel tanks<ref name=":8">{{Cite web|last=Government of British Columbia|title=Recovering Together: November 2021 Atmospheric River|url=https://storymaps.arcgis.com/stories/ecff219fba9f453bbf0f771918ccdd7b|url-status=live|access-date=12 April, 2026}}</ref>. Additionally, rivers experienced pollution through shipping containers and damaged bridges, further contributing to environmental degradation. The impacts of the debris posed risks to public safety, water quality, and infrastructure. In addition to human made debris, waterways experienced extensive damage through the distribution of natural debris. Rivers were affected by the runoff of logs and fuel left by wildfire, uprooted trees due to erosion, along with the accumulation of rocks and boulders in river beds<ref name=":8" />. With the presence of natural debris, buildups obstructed water flow, compromised the structure of many water ways and increased risk to further damage in the future flooding events.

The overall impact of the flood debris led to extensive damage to the Nicola Valley area, affecting the livelihoods of many Indigenous communities.

=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />. In addition to flood damage to farmers, the Insurance Bureau of Canada reported an estimated $9 billion Canadian dollars (CAD) in insured damages, contributing to the further economic impacts <ref>{{Cite web|last=S. Richards-Thomas, J. Déry, E. Stewart, M. Thériault,|first=Tamar, Stephen J. Déry, Ronald, Julie|date=12 June, 2024|title=Climatological context of the mid-November 2021 floods in the province of British Columbia, Canada|url=https://www.sciencedirect.com/science/article/pii/S2212094724000665|url-status=live|access-date=10 April, 2026}}</ref>. Power outages also contributed to further economic damage.

Large impacts of the flooding was also seen on British Columbia's roads. In 2023, the British Columbia Transportation Ministry said that it was expected that the repairs for major damages to BC's highways had grown to approximately $1 billion. At the time, $250 million in repairs had been done on highways one (the Trans-Canada highway), five, and eight. However, more repairs were needed to restore the British Columbia's highways and attempt to make them more resilient to future atmospheric rivers and flooding, which is why Rob Fleming, BC's Transportation Minister, estimated that the government would likely end up spending around $1 billion<ref>{{Cite news|url=https://globalnews.ca/news/9468280/highway-flood-repairs-1billion/|title=B.C. highway flood repair costs expected to balloon to $1 billion|last=Garrett|first=Catherine|date=February 7, 2023|work=Global News|access-date=April 11, 2026}}</ref>.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response and Recovery Efforts ==

The provincial government of British Columbia declared a state of emergency and implemented a variety of disaster responses in the event of BC's 2021 floods. This prompted organized activity across many levels of the Canadian government, which includes municipal, provincial, and federal agencies to come together to discuss the best strategies to manage the crises and mitigate the impact. The different levels of the Canadian government came up with many ways to respond with recovery and evacuation plans as well as emergency response units to address damage to infrastructure, the environment, and the evacuation of affected communities . Initiatives from the provincial government focused on post-flood repair and clean up by implementing flood debris management programs to restore and improve waterways <ref name=":6" />.

Water quality assessments were conducted by researchers and the government to evaluate and record potential pollutants in the water within the Fraser River Valley area after the floods. Floodwaters can carry contaminants from excess sediment, agricultural run off, and many more sources which can negatively impact the the surrounding environment and human health. Additionally, the research group wanted to determine if the flood event caused accelerated pollution of contaminants compared to average rainfalls to track changes in water composition, ensuring that contamination levels do not further worsen beyond expectations<ref name=":5" />.

Infrastructure of highways and railways where prioritized for repair from flood and landslide damage by the government as they were critical transportation and trade routes. Repair crews often had to reconstruct entire sections of highways due to erosion while reinforcing them to prevent similar events from happening in the future by implementing reinforced structure and better drainage systems. These repairs reconnected the Lower Mainland with the rest of Canada, which reactivated many supply chains<ref name=":3" />.

[[File:Screenshot 2026-03-08 at 9.26.41 PM.png|thumb|340x340px|Minister Kelly Greene and Minister Lana Popham meet with Abbotsford Mayor Ross Siemens and technical experts to give the latest update on flood response in British Columbia. Following the update, Minister Greene and the Mayor toured areas impacted by the atmospheric river and the emergency operations centre. December 12, 2026. ]]

== Future Recommendations and Preventative Measures ==
Following the recovery efforts, several preventative measures were put into place in order to prevent further flooding across British Columbia's lower mainland - from upstream of Fraser Valley all the way down to the Pacific Ocean <ref name=":32">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. The most widespread measure used across this area is dikes, large engineered barriers intended to prevent flooding by either containing, or separating the water from the land. Despite a numerous dikes being in place, Principle Flood Management Engineer Monica Mannerström noted that a study found 87% of dikes to be "in less-than-fair condition" and that 71% simply wouldn't hold in the event of a flood, rendering them useless <ref name=":32" />.

Along with the dikes, a water pump system upgrade was deemed necessary in order for the location to be flood safe going forward. Despite having this knowledge for many years, there has been no action to actually improve upon the current status of the different emplacements. Part of the reason that no real progress has been made to upgrade the preventative measures is because according to Henry Braun, the cost of operations to meet the provint [[File:54989012923 95b4e84af5 o.jpg|thumb|Premier David Eby, Minister Kelly Greene, Minister Lana Popham and others visit Abbotsford on December 15, 2026. ]]

==References==

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

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[[Category:Conservation]]

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-12T04:11:20Z

MaxForman:

= Environmental and Social Impacts of the 2021 Flooding Season in Southern BC =
== Introduction ==
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
== History of the Sumas Prairie and its Colonization ==
The Sumas prairie has experienced extreme change to appear the way that it does today. Historically, the eastern part of the Sumas Prairie was occupied by Sumas Lake, before its eventual draining for agricultural purposes between 1920 and 1924. Farmers sought the fertile soil at the bottom of the lake<ref>{{Cite web|date=January 7, 2025|title=Sumas River and Canal|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects/sumas-river-and-canal|url-status=live|website=Government of British Columbia}}</ref>.

Historically, Sumas Lake saw much natural variability, which mainly was caused by the Lake's connection to the Fraser River, which is in turn connected to the Pacific Ocean. The water levels of the Fraser River typically rise in the summer due to snowmelt. This unpredictability in the Fraser directly translated to the Sumas Lake, with the water levels of the Lake seeing large changes in depth and size depending on the season, snowmelt, and even the Pacific tides<ref name=":7">{{Cite journal|last=Murton|first=James|date=January 2008|title=Creating Order: the Liberals, the Landowners, and the Draining of Sumas Lake, British Columbia|url=https://www.proquest.com/docview/216123962/fulltextPDF/D6152C190D6F41EBPQ/1?accountid=14656&sourcetype=Scholarly%20Journals|journal=Environmental History|via=ProQuest}}</ref>.

The Stó:lō people are an Indigenous group that have historically inhabited the Fraser Valley for at least 4,000 years. They had a deep connection to Sumas Lake, both for cultural purposes and for fishing. In 1858, the discovery of gold in the Fraser Valley meant that the Stó:lō were forced into reserves by James Douglas, British Columbia's governor<ref name=":7" />. In the 1970s, there began to be discussion and legislation surrounding diking the Sumas Lake. By 1920, the conversation had shifted towards draining the lake, with hopes of accessing the fertile soil at the bottom of the Sumas Lake and avoiding its unpredictable shifts. By June 26, 1924, the Sumas Lake was gone<ref name=":7" />. Today, the lake remains drained and is mostly covered by agricultural lands.

==Converging Factors and Causes of Flooding==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

In addition to the unprecedented atmospheric river, the Sumas lake was a contributing factor to the severity of flooding. Between the Sumas Mountain and Vedder Mountain in the Lower Fraser Valley, the Sumas lake was historically the center of a dynamic floodplain landscape<ref name=":4" />. The Indigenous food system in the area was supported by a high amount of animal and plant life<ref name=":4" />. In addition to its biodiversity, the lake could vary from an area of 9,000 acres (3,642 ha) and a depth of 3 meters in the winter, to an area of 26,000 acres (10,522 ha) and depth of 11 meters in the spring<ref name=":4" />. During the past 150 years, the Lower Fraser has seen changes within its vast network of rivers, creeks, wetlands, and floodplains. These ecosystems have been developed into a series of ditches, canals, dikes, floodgates, and agricultural fields, in an effort to further residential and urban development in the area<ref name=":4" />. The changes in the lake's historical wide array of seasonal depth and the progression of urban development resulted in 30% of native vegetation remaining intact and over 85% of floodplain habitat and 64% of streams being lost<ref name=":4" />. In the early 1920's, The Sumas Lake was drained after an act in a Canada-wide process of land dispossession from Indigenous peoples in Canada<ref name=":4" />. The loss of traditional use and knowledge resulted in mismanagement practices that increased the flood risk in the area. By the mid 1920's, a plan was put in motion to drain the lake in order to further expand agricultural practices in the area. By 1924, the Chilliwack River had been diverted west, draining the lake through the Sumas Drainage Canal and into the Fraser River around the northeastern tip of the Sumas Mountain<ref name=":4" />. Despite the loss of the lake, the low elevation remained, resulting in permanent flood risk for the newly developed agricultural area.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, the nature and infrastructure in the Southern BC area, as well as citizens of that area.

=== Human Impacts ===

During the floods and the resulting landslides, five individuals were confirmed dead, with well over 3,000 residents forced out of their homes and evacuated in the Abbotsford area alone <ref name=":4">{{Cite web|last=Finn et al.|date=02 June 2024|title=Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake|url=https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2024.1380083/full|url-status=live|access-date=08 March 2026}}</ref>. In the Sumas Prairie, the former Sumas Lake refilled, displacing thousands and destroying homes built on the historic lake bed<ref name=":4" />. Farms, homes, businesses, and transportation corridors flooded, causing destruction to livelihoods and infrastructure. Many of those affected by the flooding, were not aware that their homes and farms were located on a former lakebed—Sumas Lake.

Floodwaters transported significant amounts of debris, sediment, and bacteria. E. coli counts at several locations, such as the Pitt Meadows Shoreline, exceeded Canadian Drinking Water Quality Guidelines (CDWQG) following sanitary sewer overflows <ref name=":5">{{Cite web|last=Minton et al.|date=June 2022|title=Water Quality Assessment of the Fraser River Following
the November 2021 Floods|url=https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/flood-response-and-the-environment/water-quality/water_quality_assessment_of_fraser_river_2021_floods.pdf|url-status=live|access-date=09 March 2026}}</ref>. Sanitary sewer overflows (SSOs) and the overflow of septic systems led to dangerous spikes in bacteria and other waterborne pathogens which pose risks to human health <ref name=":5" />.

Due to the flooding, many were forced to stay home and not travel within the flooded region for extended periods of time. For many days during November of 2021, using smartphone tracking data, it was found that there was virtually no travel between the cities of Hope, Merritt, and Chilliwack (all three are within the Fraser Valley and were affected by the floods)<ref>{{Cite journal|last=Liao|first=Enqi|date=May 24, 2024|title=Travel Behavior during the 2021 British Columbia Floods Using De-identified Network Mobility Data|url=doi.org/10.32866/001c.117422|journal=Resilience Findings}}</ref>. In the following weeks, travel between the cities slowly began to increase, but it took extended time for typical travel between the cities to return.
=== Environmental Impacts ===

The floods severely degraded the Lower Fraser Valley's critical habitat, which is essential for Pacific salmon and sturgeon. Rapidly rising waters caused massive sediment movement which buried salmon spawning grounds and destroyed eggs. Scientists note that the full impact on salmon populations may not be known until their 2 to 5 year life cycles are complete in spawning season of 2026 <ref>{{Cite web|last=DFO|date=2022|title=Extreme environmental impacts on Pacific salmon|url=https://www.pac.dfo-mpo.gc.ca/pacific-smon-pacifique/environmental-impacts-environnementaux-eng.html|url-status=live|access-date=09 March 2026}}</ref>.

Excessive nutrients (nitrogen and phosphorus) washed into slow moving bodies of water from farmland, leading to eutrophication. Eutrophication occurs when nutrient runoff (often from agricultural fertilizers) causes rapid algal growth. When the algae dies, the bacteria that decompose the algae consume dissolved oxygen, creating hypoxic (not enough oxygen) conditions. These hypoxic conditions can suffocate aquatic organisms <ref>{{Cite web|last=Ross et al.|date=November 2022|title=A lake re-emerges: Analysis of contaminants in the Semá:th X̱ó:tsa (Sumas Lake) region following the BC floods of 2021|url=https://www.raincoast.org/reports/flood/|url-status=live|access-date=09 March 2026}}</ref>.

The death of over 670,000 farm animals created a biological hazard through an increase of immediate groundwater contamination and the spread of disease <ref name=":6">{{Cite web|last=Province of British Columbia|date=2024|title=Flood debris management projects|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects|url-status=live|access-date=09 March 2026}}</ref>. Crews eventually removed over 16,000 metric tons of natural and man-made debris (including 98 vehicles and 4 bridges) from provincial waterways to prevent further ecological blockages from occurring as a result of the floods <ref name=":6" />.
=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />. In addition to flood damage to farmers, the Insurance Bureau of Canada reported an estimated $9 billion Canadian dollars (CAD) in insured damages, contributing to the further economic impacts <ref>{{Cite web|last=S. Richards-Thomas, J. Déry, E. Stewart, M. Thériault,|first=Tamar, Stephen J. Déry, Ronald, Julie|date=12 June, 2024|title=Climatological context of the mid-November 2021 floods in the province of British Columbia, Canada|url=https://www.sciencedirect.com/science/article/pii/S2212094724000665|url-status=live|access-date=10 April, 2026}}</ref>. Power outages also contributed to further economic damage.

Large impacts of the flooding was also seen on British Columbia's roads. In 2023, the British Columbia Transportation Ministry said that it was expected that the repairs for major damages to BC's highways had grown to approximately $1 billion. At the time, $250 million in repairs had been done on highways one (the Trans-Canada highway), five, and eight. However, more repairs were needed to restore the British Columbia's highways and attempt to make them more resilient to future atmospheric rivers and flooding, which is why Rob Fleming, BC's Transportation Minister, estimated that the government would likely end up spending around $1 billion<ref>{{Cite news|url=https://globalnews.ca/news/9468280/highway-flood-repairs-1billion/|title=B.C. highway flood repair costs expected to balloon to $1 billion|last=Garrett|first=Catherine|date=February 7, 2023|work=Global News|access-date=April 11, 2026}}</ref>.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response and Recovery Efforts ==

The provincial government of British Columbia declared a state of emergency and implemented a variety of disaster responses in the event of BC's 2021 floods. This caused Canadian Governments of many levels to respond with recovery and evacuation plans as well as emergency response units to address damage to infrastructure, the environment, and the evacuation of affected communities . Initiatives from the provincial government focused on post-flood repair and clean up by implementing flood debris management programs to restore and improve waterways <ref name=":6" />.

Water quality assessments were conducted by researchers and the government to evaluate and record potential pollutants in the water within the Fraser River Valley area after the floods. Additionally, the research group wanted to determine if the flood event caused accelerated pollution of contaminants compared to average rainfalls to track changes in water composition, ensuring that contamination levels do not further worsen beyond expectations<ref name=":5" />.

Infrastructure of highways and railways where prioritized for repair from flood and landslide damage by the government as they were critical transportation and trade routes. Repair crews often had to reconstruct entire sections of highways due to erosion while reinforcing them to prevent similar events from happening in the future. These repairs reconnected the Lower Mainland with the rest of Canada, which reactivated many supply chains<ref name=":3" />.

[[File:Screenshot 2026-03-08 at 9.26.41 PM.png|thumb|340x340px|Minister Kelly Greene and Minister Lana Popham meet with Abbotsford Mayor Ross Siemens and technical experts to give the latest update on flood response in British Columbia. Following the update, Minister Greene and the Mayor toured areas impacted by the atmospheric river and the emergency operations centre. December 12, 2026. ]]

== Future Recommendations and Preventative Measures ==
Following the recovery efforts, several preventative measures were put into place in order to prevent further flooding across British Columbia's lower mainland - from upstream of Fraser Valley all the way down to the Pacific Ocean <ref name=":32">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. The most widespread measure used across this area is dikes, large engineered barriers intended to prevent flooding by either containing, or separating the water from the land. Despite a numerous dikes being in place, Principle Flood Management Engineer Monica Mannerström noted that a study found 87% of dikes to be "in less-than-fair condition" and that 71% simply wouldn't hold in the event of a flood, rendering them useless <ref name=":32" />.

Along with the dikes, a water pump system upgrade was deemed [[File:54989012923 95b4e84af5 o.jpg|thumb|Premier David Eby, Minister Kelly Greene, Minister Lana Popham and others visit Abbotsford on December 15, 2026. ]]

==References==

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]

Course:CONS200/Projects

2026-04-11T23:39:56Z

MaxForman:

{{Start tab|
| tab-1 = Guidelines
| link-1 = Course:CONS200
| tab-3 = 2026
| link-3 = Course:CONS200/Projects
| tab-4 = Past Projects
| link-4 = Course:CONS200/Samples
| tab-5 = Help and Resources
| link-5 = Course:CONS200/Help and Resources
}}

==Create Your Wiki Page==
===1. Login to the UBC Wiki===
Click the CWL button on the top of the page and login from there.

===2. Find your Project page===
Find your project page from the table below. If you don't see your project, create the wiki page using the box below:

<inputbox>
useve=yes
placeholder=project title here
preload=Course:CONS200/Sample Assignment Page
prefix=Course:CONS200/2026WT2/
type=create

</inputbox>

===3. Begin Writing! ===
Click the "Edit" button to start editing your wiki page! Your new wiki page will be created with some suggested headings and sections.
==Project Table==

After you have created your project page, please add your information to the project below. You can edit the table by double clicking on the table.
{| class="wikitable"
|+
!Group
!Project Title
|-
|Test
|[[Course:CONS200/2026WT2/Rie's test project 2|Rie's project]]
|-
|Group 1
|[[Course:CONS200/2026WT2/Climate change impacts on Western red cedar|Climate change impacts on Western red cedar]]
|-
|Group 2
|[https://wiki.ubc.ca/index.php?title=Course%3ACONS200%2F2026WT2%2FGroup_2%3A_Human_Black_Bear_%28Ursus_Americanus%29_conflict_in_British_Columbia%3A_Status_and_potential_solutions&redirect=no Human Black Bear (Ursus Americanus) conflict in British Columbia: Status and potential solutions]
|-
|Group 3
|[[Course:CONS200/2026WT2/Strategies, opportunities and challenges for biodiversity conservation in Sicily|Strategies, opportunities and challenges for biodiversity conservation in Sicily]]
|-
|Group 4
|[[Course:CONS200/2026WT2/Grassland Ecosystem Conservation and Indigenous Stewardship in the BC Interior|Grassland Ecosystem Conservation and Indigenous Stewardship in the BC Interior]]
|-
|Group 5
|[[Healing Reefs with Sound: The Potential of Acoustic Enrichment]]
|-
|Group 6
|[[Course:CONS200/2026WT2/Illegal logging in Ecuador: Drivers, impacts and potential solutions|Illegal logging in Ecuador: Drivers, impacts and potential solutions]]
|-
|Group 7
|[[Course:CONS200/2026WT2/Organized crime and illegal mining in Latin America|Organized crime and illegal mining in Latin America]]
|-
|Group 8
|[[Course:CONS200/2026WT2/The Use of Prescribed Burning in Sweden for Conservation and Biodiversity Outcomes]]
|-
|Group 9
|[[Course:CONS200/2026WT2/Chimpanzee-human interactions in Uganda: Is a sustainable co-existence possible?|Chimpanzee-human interactions in Uganda: Is a sustainable co-existence possible?]]
|-
|Group 10
|[[Course:CONS200/2026WT2/ Rewilding Europe: Reviewing Continent-Wide Strategies|Rewilding Europe: Reviewing Continent-Wide Strategies]]
|-
|Group 11
|
|-
|Group 12
|[[Course:CONS200/2026WT2/Marine and Reef Conservation in the Hawaiian Islands]]
|-
|Group 13
|
|-
|Group 14
|[[Course:CONS200/2026WT2/Conflicts and potential solutions between the forestry sector and Sámi reindeer husbandry in Sweden]]
|-
|Group 15
|[[Course:CONS200/2026WT2/Orcas (Orcinus orca) and climate change in the Arctic: Status and impact|Orcas (Orcinus orca) and climate change in the Arctic: Status and impact]]
|-
|Group 16
|[[Course:CONS200/2026WT2/Narco-deforestation and degradation in Central America: Status and potential solutions|Narco-deforestation and degradation in Central America]]
|-
|Group 18
|Salmonid Colonization: Glacier Retreat And The Creation of New Habitat for Salmon in a Changing Climate
|-
|Group 19
|[[Course:CONS200/2026WT2/Jaguars (Panthera onca) in Mexico: Status and conservation|Jaguars (Panthera onca) in Mexico: Status and conservation]]
|-
|Group 20
|[[The Impacts of Urbanization on Mule Deer in British Columbia]]
|-
|Group 21
|[[Course:CONS200/2026WT2/Conservation challenges and Indigenous cultural significance of eulachon in the Fraser River|Conservation challenges and Indigenous cultural significance of eulachon in the Fraser River]]
|-
|Group 22
|[https://wiki.ubc.ca/Course:CONS200/2026WT2/Authoritarian_Environmentalism_in_China%27s_The_Top_Ten-Thousand_Enterprises_Programme Authoritarian environmentalism: A case study of China’s Ten Thousand Enterprises Energy Conservation Low-Carbon Programme]
|-
|Group 23
|Conservation technology and illegal poaching in Sub-Saharan Africa: An overview of its effectiveness
|-
|Group 28
|[[Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC|Environmental and Social Impacts of the 2021 Flooding Season in Southern BC]]

|-
|Group 29
|Snow Leopards (Panthera uncia) and Climate Change: What's the story in the Himalayas?
|-
|group 25
|The impacts of tourism on Subak conservation in Bali, Indonesia
|}

==Project Template==
This project template is only a guide for your wiki page. You can modify it depending on your topic. Click on the link to your topic to begin editing:
*
[[Course:CONS200/Sample Assignment Page|Project Template]]

==Project Listings(Auto Generated)==

<dpl>
titlematch=CONS200/2026WT2/%
namespace=Course
shownamespace=false
replaceintitle=$CONS200/2026WT2/$,
allowcachedresults=false
format=,\n* [[%PAGE%|%TITLE%]],,
</dpl>

Course:CONS200/Projects

2026-04-11T23:38:47Z

MaxForman:

{{Start tab|
| tab-1 = Guidelines
| link-1 = Course:CONS200
| tab-3 = 2026
| link-3 = Course:CONS200/Projects
| tab-4 = Past Projects
| link-4 = Course:CONS200/Samples
| tab-5 = Help and Resources
| link-5 = Course:CONS200/Help and Resources
}}

==Create Your Wiki Page==
===1. Login to the UBC Wiki===
Click the CWL button on the top of the page and login from there.

===2. Find your Project page===
Find your project page from the table below. If you don't see your project, create the wiki page using the box below:

<inputbox>
useve=yes
placeholder=project title here
preload=Course:CONS200/Sample Assignment Page
prefix=Course:CONS200/2026WT2/
type=create

</inputbox>

===3. Begin Writing! ===
Click the "Edit" button to start editing your wiki page! Your new wiki page will be created with some suggested headings and sections.
==Project Table==

After you have created your project page, please add your information to the project below. You can edit the table by double clicking on the table.
{| class="wikitable"
|+
!Group
!Project Title
|-
|Test
|[[Course:CONS200/2026WT2/Rie's test project 2|Rie's project]]
|-
|Group 1
|[[Course:CONS200/2026WT2/Climate change impacts on Western red cedar|Climate change impacts on Western red cedar]]
|-
|Group 2
|[https://wiki.ubc.ca/index.php?title=Course%3ACONS200%2F2026WT2%2FGroup_2%3A_Human_Black_Bear_%28Ursus_Americanus%29_conflict_in_British_Columbia%3A_Status_and_potential_solutions&redirect=no Human Black Bear (Ursus Americanus) conflict in British Columbia: Status and potential solutions]
|-
|Group 3
|[[Course:CONS200/2026WT2/Strategies, opportunities and challenges for biodiversity conservation in Sicily|Strategies, opportunities and challenges for biodiversity conservation in Sicily]]
|-
|Group 4
|[[Course:CONS200/2026WT2/Grassland Ecosystem Conservation and Indigenous Stewardship in the BC Interior|Grassland Ecosystem Conservation and Indigenous Stewardship in the BC Interior]]
|-
|Group 5
|[[Healing Reefs with Sound: The Potential of Acoustic Enrichment]]
|-
|Group 6
|[[Course:CONS200/2026WT2/Illegal logging in Ecuador: Drivers, impacts and potential solutions|Illegal logging in Ecuador: Drivers, impacts and potential solutions]]
|-
|Group 7
|[[Course:CONS200/2026WT2/Organized crime and illegal mining in Latin America|Organized crime and illegal mining in Latin America]]
|-
|Group 8
|[[Course:CONS200/2026WT2/The Use of Prescribed Burning in Sweden for Conservation and Biodiversity Outcomes]]
|-
|Group 9
|[[Course:CONS200/2026WT2/Chimpanzee-human interactions in Uganda: Is a sustainable co-existence possible?|Chimpanzee-human interactions in Uganda: Is a sustainable co-existence possible?]]
|-
|Group 10
|[[Course:CONS200/2026WT2/ Rewilding Europe: Reviewing Continent-Wide Strategies|Rewilding Europe: Reviewing Continent-Wide Strategies]]
|-
|Group 11
|
|-
|Group 12
|[[Course:CONS200/2026WT2/Marine and Reef Conservation in the Hawaiian Islands]]
|-
|Group 13
|
|-
|Group 14
|[[Course:CONS200/2026WT2/Conflicts and potential solutions between the forestry sector and Sámi reindeer husbandry in Sweden]]
|-
|Group 15
|[[Course:CONS200/2026WT2/Orcas (Orcinus orca) and climate change in the Arctic: Status and impact|Orcas (Orcinus orca) and climate change in the Arctic: Status and impact]]
|-
|Group 16
|[[Course:CONS200/2026WT2/Narco-deforestation and degradation in Central America: Status and potential solutions|Narco-deforestation and degradation in Central America]]
|-
|Group 18
|Salmonid Colonization: Glacier Retreat And The Creation of New Habitat for Salmon in a Changing Climate
|-
|Group 19
|[[Course:CONS200/2026WT2/Jaguars (Panthera onca) in Mexico: Status and conservation|Jaguars (Panthera onca) in Mexico: Status and conservation]]
|-
|Group 20
|[[The Impacts of Urbanization on Mule Deer in British Columbia]]
|-
|Group 21
|[[Course:CONS200/2026WT2/Conservation challenges and Indigenous cultural significance of eulachon in the Fraser River|Conservation challenges and Indigenous cultural significance of eulachon in the Fraser River]]
|-
|Group 22
|[https://wiki.ubc.ca/Course:CONS200/2026WT2/Authoritarian_Environmentalism_in_China%27s_The_Top_Ten-Thousand_Enterprises_Programme Authoritarian environmentalism: A case study of China’s Ten Thousand Enterprises Energy Conservation Low-Carbon Programme]
|-
|Group 23
|Conservation technology and illegal poaching in Sub-Saharan Africa: An overview of its effectiveness
|-
|Group 28
|
* [[Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC|Environmental and social impacts of the 2021 flooding season in southern BC]]
|-
|Group 29
|Snow Leopards (Panthera uncia) and Climate Change: What's the story in the Himalayas?
|-
|group 25
|The impacts of tourism on Subak conservation in Bali, Indonesia
|}

==Project Template==
This project template is only a guide for your wiki page. You can modify it depending on your topic. Click on the link to your topic to begin editing:
*
[[Course:CONS200/Sample Assignment Page|Project Template]]

==Project Listings(Auto Generated)==

<dpl>
titlematch=CONS200/2026WT2/%
namespace=Course
shownamespace=false
replaceintitle=$CONS200/2026WT2/$,
allowcachedresults=false
format=,\n* [[%PAGE%|%TITLE%]],,
</dpl>

Course:CONS200/Projects

2026-04-11T23:37:34Z

MaxForman: /* Project Table */

{{Start tab|
| tab-1 = Guidelines
| link-1 = Course:CONS200
| tab-3 = 2026
| link-3 = Course:CONS200/Projects
| tab-4 = Past Projects
| link-4 = Course:CONS200/Samples
| tab-5 = Help and Resources
| link-5 = Course:CONS200/Help and Resources
}}

==Create Your Wiki Page==
===1. Login to the UBC Wiki===
Click the CWL button on the top of the page and login from there.

===2. Find your Project page===
Find your project page from the table below. If you don't see your project, create the wiki page using the box below:

<inputbox>
useve=yes
placeholder=project title here
preload=Course:CONS200/Sample Assignment Page
prefix=Course:CONS200/2026WT2/
type=create

</inputbox>

===3. Begin Writing! ===
Click the "Edit" button to start editing your wiki page! Your new wiki page will be created with some suggested headings and sections.
==Project Table==

After you have created your project page, please add your information to the project below. You can edit the table by double clicking on the table.
{| class="wikitable"
|+
!Group
!Project Title
|-
|Test
|[[Course:CONS200/2026WT2/Rie's test project 2|Rie's project]]
|-
|Group 1
|[[Course:CONS200/2026WT2/Climate change impacts on Western red cedar|Climate change impacts on Western red cedar]]
|-
|Group 2
|[https://wiki.ubc.ca/index.php?title=Course%3ACONS200%2F2026WT2%2FGroup_2%3A_Human_Black_Bear_%28Ursus_Americanus%29_conflict_in_British_Columbia%3A_Status_and_potential_solutions&redirect=no Human Black Bear (Ursus Americanus) conflict in British Columbia: Status and potential solutions]
|-
|Group 3
|[[Course:CONS200/2026WT2/Strategies, opportunities and challenges for biodiversity conservation in Sicily|Strategies, opportunities and challenges for biodiversity conservation in Sicily]]
|-
|Group 4
|[[Course:CONS200/2026WT2/Grassland Ecosystem Conservation and Indigenous Stewardship in the BC Interior|Grassland Ecosystem Conservation and Indigenous Stewardship in the BC Interior]]
|-
|Group 5
|[[Healing Reefs with Sound: The Potential of Acoustic Enrichment]]
|-
|Group 6
|[[Course:CONS200/2026WT2/Illegal logging in Ecuador: Drivers, impacts and potential solutions|Illegal logging in Ecuador: Drivers, impacts and potential solutions]]
|-
|Group 7
|[[Course:CONS200/2026WT2/Organized crime and illegal mining in Latin America|Organized crime and illegal mining in Latin America]]
|-
|Group 8
|[[Course:CONS200/2026WT2/The Use of Prescribed Burning in Sweden for Conservation and Biodiversity Outcomes]]
|-
|Group 9
|[[Course:CONS200/2026WT2/Chimpanzee-human interactions in Uganda: Is a sustainable co-existence possible?|Chimpanzee-human interactions in Uganda: Is a sustainable co-existence possible?]]
|-
|Group 10
|[[Course:CONS200/2026WT2/ Rewilding Europe: Reviewing Continent-Wide Strategies|Rewilding Europe: Reviewing Continent-Wide Strategies]]
|-
|Group 11
|
|-
|Group 12
|[[Course:CONS200/2026WT2/Marine and Reef Conservation in the Hawaiian Islands]]
|-
|Group 13
|
|-
|Group 14
|[[Course:CONS200/2026WT2/Conflicts and potential solutions between the forestry sector and Sámi reindeer husbandry in Sweden]]
|-
|Group 15
|[[Course:CONS200/2026WT2/Orcas (Orcinus orca) and climate change in the Arctic: Status and impact|Orcas (Orcinus orca) and climate change in the Arctic: Status and impact]]
|-
|Group 16
|[[Course:CONS200/2026WT2/Narco-deforestation and degradation in Central America: Status and potential solutions|Narco-deforestation and degradation in Central America]]
|-
|Group 18
|Salmonid Colonization: Glacier Retreat And The Creation of New Habitat for Salmon in a Changing Climate
|-
|Group 19
|[[Course:CONS200/2026WT2/Jaguars (Panthera onca) in Mexico: Status and conservation|Jaguars (Panthera onca) in Mexico: Status and conservation]]
|-
|Group 20
|[[The Impacts of Urbanization on Mule Deer in British Columbia]]
|-
|Group 21
|[[Course:CONS200/2026WT2/Conservation challenges and Indigenous cultural significance of eulachon in the Fraser River|Conservation challenges and Indigenous cultural significance of eulachon in the Fraser River]]
|-
|Group 22
|[https://wiki.ubc.ca/Course:CONS200/2026WT2/Authoritarian_Environmentalism_in_China%27s_The_Top_Ten-Thousand_Enterprises_Programme Authoritarian environmentalism: A case study of China’s Ten Thousand Enterprises Energy Conservation Low-Carbon Programme]
|-
|Group 23
|Conservation technology and illegal poaching in Sub-Saharan Africa: An overview of its effectiveness
|-
|Group 28
|
|-
|Group 29
|Snow Leopards (Panthera uncia) and Climate Change: What's the story in the Himalayas?
|-
|group 25
|The impacts of tourism on Subak conservation in Bali, Indonesia
|}

==Project Template==
This project template is only a guide for your wiki page. You can modify it depending on your topic. Click on the link to your topic to begin editing:
*
[[Course:CONS200/Sample Assignment Page|Project Template]]

==Project Listings(Auto Generated)==

<dpl>
titlematch=CONS200/2026WT2/%
namespace=Course
shownamespace=false
replaceintitle=$CONS200/2026WT2/$,
allowcachedresults=false
format=,\n* [[%PAGE%|%TITLE%]],,
</dpl>

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-11T23:25:19Z

MaxForman: /* Human Impacts */

= Environmental and Social Impacts of the 2021 Flooding Season in Southern BC =
== Introduction ==
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
== History of the Sumas Prairie and its Colonization ==
The Sumas prairie has experienced extreme change to appear the way that it does today. Historically, the eastern part of the Sumas Prairie was occupied by Sumas Lake, before its eventual draining for agricultural purposes between 1920 and 1924. Farmers sought the fertile soil at the bottom of the lake<ref>{{Cite web|date=January 7, 2025|title=Sumas River and Canal|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects/sumas-river-and-canal|url-status=live|website=Government of British Columbia}}</ref>.

Historically, Sumas Lake saw much natural variability, which mainly was caused by the Lake's connection to the Fraser River, which is in turn connected to the Pacific Ocean. The water levels of the Fraser River typically rise in the summer due to snowmelt. This unpredictability in the Fraser directly translated to the Sumas Lake, with the water levels of the Lake seeing large changes in depth and size depending on the season, snowmelt, and even the Pacific tides<ref name=":7">{{Cite journal|last=Murton|first=James|date=January 2008|title=Creating Order: the Liberals, the Landowners, and the Draining of Sumas Lake, British Columbia|url=https://www.proquest.com/docview/216123962/fulltextPDF/D6152C190D6F41EBPQ/1?accountid=14656&sourcetype=Scholarly%20Journals|journal=Environmental History|via=ProQuest}}</ref>.

The Stó:lō people are an Indigenous group that have historically inhabited the Fraser Valley for at least 4,000 years. They had a deep connection to Sumas Lake, both for cultural purposes and for fishing. In 1858, the discovery of gold in the Fraser Valley meant that the Stó:lō were forced into reserves by James Douglas, British Columbia's governor<ref name=":7" />. In the 1970s, there began to be discussion and legislation surrounding diking the Sumas Lake. By 1920, the conversation had shifted towards draining the lake, with hopes of accessing the fertile soil at the bottom of the Sumas Lake and avoiding its unpredictable shifts. By June 26, 1924, the Sumas Lake was gone<ref name=":7" />. Today, the lake remains drained and is mostly covered by agricultural lands.

==Converging Factors and Causes of Flooding==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

In addition to the unprecedented atmospheric river, the Sumas lake was a contributing factor to the severity of flooding. Between the Sumas Mountain and Vedder Mountain in the Lower Fraser Valley, the Sumas lake was historically the center of a dynamic floodplain landscape<ref name=":4" />. The Indigenous food system in the area was supported by a high amount of animal and plant life<ref name=":4" />. In addition to its biodiversity, the lake could vary from an area of 9,000 acres (3,642 ha) and a depth of 3 meters in the winter, to an area of 26,000 acres (10,522 ha) and depth of 11 meters in the spring<ref name=":4" />. During the past 150 years, the Lower Fraser has seen changes within its vast network of rivers, creeks, wetlands, and floodplains. These ecosystems have been developed into a series of ditches, canals, dikes, floodgates, and agricultural fields, in an effort to further residential and urban development in the area<ref name=":4" />. The changes in the lake's historical wide array of seasonal depth and the progression of urban development resulted in 30% of native vegetation remaining intact and over 85% of floodplain habitat and 64% of streams being lost<ref name=":4" />. In the early 1920's, The Sumas Lake was drained after an act in a Canada-wide process of land dispossession from Indigenous peoples in Canada<ref name=":4" />. The loss of traditional use and knowledge resulted in mismanagement practices that increased the flood risk in the area. By the mid 1920's, a plan was put in motion to drain the lake in order to further expand agricultural practices in the area. By 1924, the Chilliwack River had been diverted west, draining the lake through the Sumas Drainage Canal and into the Fraser River around the northeastern tip of the Sumas Mountain<ref name=":4" />. Despite the loss of the lake, the low elevation remained, resulting in permanent flood risk for the newly developed agricultural area.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, the nature and infrastructure in the Southern BC area, as well as citizens of that area.

=== Human Impacts ===

During the floods and the resulting landslides, five individuals were confirmed dead, with well over 3,000 residents forced out of their homes and evacuated in the Abbotsford area alone <ref name=":4">{{Cite web|last=Finn et al.|date=02 June 2024|title=Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake|url=https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2024.1380083/full|url-status=live|access-date=08 March 2026}}</ref>. In the Sumas Prairie, the former Sumas Lake refilled, displacing thousands and destroying homes built on the historic lake bed<ref name=":4" />. Farms, homes, businesses, and transportation corridors flooded, causing destruction to livelihoods and infrastructure. Many of those affected by the flooding, were not aware that their homes and farms were located on a former lakebed—Sumas Lake.

Floodwaters transported significant amounts of debris, sediment, and bacteria. E. coli counts at several locations, such as the Pitt Meadows Shoreline, exceeded Canadian Drinking Water Quality Guidelines (CDWQG) following sanitary sewer overflows <ref name=":5">{{Cite web|last=Minton et al.|date=June 2022|title=Water Quality Assessment of the Fraser River Following
the November 2021 Floods|url=https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/flood-response-and-the-environment/water-quality/water_quality_assessment_of_fraser_river_2021_floods.pdf|url-status=live|access-date=09 March 2026}}</ref>. Sanitary sewer overflows (SSOs) and the overflow of septic systems led to dangerous spikes in bacteria and other waterborne pathogens which pose risks to human health <ref name=":5" />.

Due to the flooding, many were forced to stay home and not travel within the flooded region for extended periods of time. For many days during November of 2021, using smartphone tracking data, it was found that there was virtually no travel between the cities of Hope, Merritt, and Chilliwack (all three are within the Fraser Valley and were affected by the floods)<ref>{{Cite journal|last=Liao|first=Enqi|date=May 24, 2024|title=Travel Behavior during the 2021 British Columbia Floods Using De-identified Network Mobility Data|url=doi.org/10.32866/001c.117422|journal=Resilience Findings}}</ref>. In the following weeks, travel between the cities slowly began to increase, but it took extended time for typical travel between the cities to return.
=== Environmental Impacts ===

The floods severely degraded the Lower Fraser Valley's critical habitat, which is essential for Pacific salmon and sturgeon. Rapidly rising waters caused massive sediment movement which buried salmon spawning grounds and destroyed eggs. Scientists note that the full impact on salmon populations may not be known until their 2 to 5 year life cycles are complete in spawning season of 2026 <ref>{{Cite web|last=DFO|date=2022|title=Extreme environmental impacts on Pacific salmon|url=https://www.pac.dfo-mpo.gc.ca/pacific-smon-pacifique/environmental-impacts-environnementaux-eng.html|url-status=live|access-date=09 March 2026}}</ref>.

Excessive nutrients (nitrogen and phosphorus) washed into slow moving bodies of water, leading to eutrophication. This process depletes dissolved oxygen effectively suffocating fish and other aquatic organisms <ref>{{Cite web|last=Ross et al.|date=November 2022|title=A lake re-emerges: Analysis of contaminants in the Semá:th X̱ó:tsa (Sumas Lake) region following the BC floods of 2021|url=https://www.raincoast.org/reports/flood/|url-status=live|access-date=09 March 2026}}</ref>.

The death of over 670,000 farm animals created a biological hazard through an increase of immediate groundwater contamination and the spread of disease <ref name=":6">{{Cite web|last=Province of British Columbia|date=2024|title=Flood debris management projects|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects|url-status=live|access-date=09 March 2026}}</ref>. Crews eventually removed over 16,000 metric tons of natural and man-made debris (including 98 vehicles and 4 bridges) from provincial waterways to prevent further ecological blockages from occurring as a result of the floods <ref name=":6" />.
=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />. In addition to flood damage to farmers, the Insurance Bureau of Canada reported an estimated $9 billion Canadian dollars (CAD) in insured damages, contributing to the further economic impacts <ref>{{Cite web|last=S. Richards-Thomas, J. Déry, E. Stewart, M. Thériault,|first=Tamar, Stephen J. Déry, Ronald, Julie|date=12 June, 2024|title=Climatological context of the mid-November 2021 floods in the province of British Columbia, Canada|url=https://www.sciencedirect.com/science/article/pii/S2212094724000665|url-status=live|access-date=10 April, 2026}}</ref>. Power outages also contributed to further economic damage.

Large impacts of the flooding was also seen on British Columbia's roads. In 2023, the British Columbia Transportation Ministry said that it was expected that the repairs for major damages to BC's highways had grown to approximately $1 billion. At the time, $250 million in repairs had been done on highways one (the Trans-Canada highway), five, and eight. However, more repairs were needed to restore the British Columbia's highways and attempt to make them more resilient to future atmospheric rivers and flooding, which is why Rob Fleming, BC's Transportation Minister, estimated that the government would likely end up spending around $1 billion<ref>{{Cite news|url=https://globalnews.ca/news/9468280/highway-flood-repairs-1billion/|title=B.C. highway flood repair costs expected to balloon to $1 billion|last=Garrett|first=Catherine|date=February 7, 2023|work=Global News|access-date=April 11, 2026}}</ref>.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response and Recovery Efforts ==

The provincial government of British Columbia declared a state of emergency and implemented a variety of disaster responses in the event of BC's 2021 floods. This caused Canadian Governments of many levels to respond with recovery and evacuation plans as well as emergency response units to address damage to infrastructure, the environment, and the evacuation of affected communities . Initiatives from the provincial government focused on post-flood repair and clean up by implementing flood debris management programs to restore and improve waterways <ref name=":6" />.

Water quality assessments were conducted by researchers and the government to evaluate and record potential pollutants in the water within the Fraser River Valley area after the floods. Additionally, the research group wanted to determine if the flood event caused accelerated pollution of contaminants compared to average rainfalls to track changes in water composition, ensuring that contamination levels do not further worsen beyond expectations<ref name=":5" />.

Infrastructure of highways and railways where prioritized for repair from flood and landslide damage by the government as they were critical transportation and trade routes. Repair crews often had to reconstruct entire sections of highways due to erosion while reinforcing them to prevent similar events from happening in the future. These repairs reconnected the Lower Mainland with the rest of Canada, which reactivated many supply chains<ref name=":3" />.

[[File:Screenshot 2026-03-08 at 9.26.41 PM.png|thumb|340x340px|Minister Kelly Greene and Minister Lana Popham meet with Abbotsford Mayor Ross Siemens and technical experts to give the latest update on flood response in British Columbia. Following the update, Minister Greene and the Mayor toured areas impacted by the atmospheric river and the emergency operations centre. December 12, 2026. ]]

== Future Recommendations and Preventative Measures ==
Following the recovery efforts, several preventative measures were put into place in order to prevent further flooding across British Columbia's lower mainland - from upstream of Fraser Valley all the way down to the Pacific Ocean <ref name=":32">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. The most widespread measure used across this area is dikes, large engineered barriers intended to prevent flooding by either containing, or separating the water from the land. Despite a numerous dikes being in place, Principle Flood Management Engineer Monica Mannerström noted that a study found 87% of dikes to be "in less-than-fair condition" and that 71% simply wouldn't hold in the event of a flood, rendering them useless <ref name=":32" />.

Along with the dikes, a water pump system upgrade was deemed [[File:54989012923 95b4e84af5 o.jpg|thumb|Premier David Eby, Minister Kelly Greene, Minister Lana Popham and others visit Abbotsford on December 15, 2026. ]]

==References==

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-11T23:15:15Z

MaxForman: /* History of the Sumas Prairie and its Colonization */

= Environmental and Social Impacts of the 2021 Flooding Season in Southern BC =
== Introduction ==
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
== History of the Sumas Prairie and its Colonization ==
The Sumas prairie has experienced extreme change to appear the way that it does today. Historically, the eastern part of the Sumas Prairie was occupied by Sumas Lake, before its eventual draining for agricultural purposes between 1920 and 1924. Farmers sought the fertile soil at the bottom of the lake<ref>{{Cite web|date=January 7, 2025|title=Sumas River and Canal|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects/sumas-river-and-canal|url-status=live|website=Government of British Columbia}}</ref>.

Historically, Sumas Lake saw much natural variability, which mainly was caused by the Lake's connection to the Fraser River, which is in turn connected to the Pacific Ocean. The water levels of the Fraser River typically rise in the summer due to snowmelt. This unpredictability in the Fraser directly translated to the Sumas Lake, with the water levels of the Lake seeing large changes in depth and size depending on the season, snowmelt, and even the Pacific tides<ref name=":7">{{Cite journal|last=Murton|first=James|date=January 2008|title=Creating Order: the Liberals, the Landowners, and the Draining of Sumas Lake, British Columbia|url=https://www.proquest.com/docview/216123962/fulltextPDF/D6152C190D6F41EBPQ/1?accountid=14656&sourcetype=Scholarly%20Journals|journal=Environmental History|via=ProQuest}}</ref>.

The Stó:lō people are an Indigenous group that have historically inhabited the Fraser Valley for at least 4,000 years. They had a deep connection to Sumas Lake, both for cultural purposes and for fishing. In 1858, the discovery of gold in the Fraser Valley meant that the Stó:lō were forced into reserves by James Douglas, British Columbia's governor<ref name=":7" />. In the 1970s, there began to be discussion and legislation surrounding diking the Sumas Lake. By 1920, the conversation had shifted towards draining the lake, with hopes of accessing the fertile soil at the bottom of the Sumas Lake and avoiding its unpredictable shifts. By June 26, 1924, the Sumas Lake was gone<ref name=":7" />. Today, the lake remains drained and is mostly covered by agricultural lands.

==Converging Factors and Causes of Flooding==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

In addition to the unprecedented atmospheric river, the Sumas lake was a contributing factor to the severity of flooding. Between the Sumas Mountain and Vedder Mountain in the Lower Fraser Valley, the Sumas lake was historically the center of a dynamic floodplain landscape<ref name=":4" />. The Indigenous food system in the area was supported by a high amount of animal and plant life<ref name=":4" />. In addition to its biodiversity, the lake could vary from an area of 9,000 acres (3,642 ha) and a depth of 3 meters in the winter, to an area of 26,000 acres (10,522 ha) and depth of 11 meters in the spring<ref name=":4" />. During the past 150 years, the Lower Fraser has seen changes within its vast network of rivers, creeks, wetlands, and floodplains. These ecosystems have been developed into a series of ditches, canals, dikes, floodgates, and agricultural fields, in an effort to further residential and urban development in the area<ref name=":4" />. The changes in the lake's historical wide array of seasonal depth and the progression of urban development resulted in 30% of native vegetation remaining intact and over 85% of floodplain habitat and 64% of streams being lost<ref name=":4" />. In the early 1920's, The Sumas Lake was drained after an act in a Canada-wide process of land dispossession from Indigenous peoples in Canada<ref name=":4" />. The loss of traditional use and knowledge resulted in mismanagement practices that increased the flood risk in the area. By the mid 1920's, a plan was put in motion to drain the lake in order to further expand agricultural practices in the area. By 1924, the Chilliwack River had been diverted west, draining the lake through the Sumas Drainage Canal and into the Fraser River around the northeastern tip of the Sumas Mountain<ref name=":4" />. Despite the loss of the lake, the low elevation remained, resulting in permanent flood risk for the newly developed agricultural area.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, the nature and infrastructure in the Southern BC area, as well as citizens of that area.

=== Human Impacts ===

During the floods and the resulting landslides, five individuals were confirmed dead, with well over 3,000 residents forced out of their homes and evacuated in the Abbotsford area alone <ref name=":4">{{Cite web|last=Finn et al.|date=02 June 2024|title=Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake|url=https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2024.1380083/full|url-status=live|access-date=08 March 2026}}</ref>. In the Sumas Prairie, the former Sumas Lake refilled, displacing thousands and destroying homes built on the historic lake bed<ref name=":4" />. Farms, homes, businesses, and transportation corridors flooded, causing destruction to livelihoods and infrastructure. Many of those affected by the flooding, were not aware that their homes and farms were located on a former lakebed—Sumas Lake.

Floodwaters transported significant amounts of debris, sediment, and bacteria. E. coli counts at several locations, such as the Pitt Meadows Shoreline, exceeded Canadian Drinking Water Quality Guidelines (CDWQG) following sanitary sewer overflows <ref name=":5">{{Cite web|last=Minton et al.|date=June 2022|title=Water Quality Assessment of the Fraser River Following
the November 2021 Floods|url=https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/flood-response-and-the-environment/water-quality/water_quality_assessment_of_fraser_river_2021_floods.pdf|url-status=live|access-date=09 March 2026}}</ref>. Sanitary sewer overflows (SSOs) and the overflow of septic systems led to dangerous spikes in bacteria and other waterborne pathogens which pose risks to human health <ref name=":5" />.

Due to the flooding, many were forced to stay home and not travel within the flooded region for extended periods of time. For many days during November of 2021, using smartphone tracking data, it was found that there was virtually no travel between the cities of Hope, Merritt, and Chilliwack (all three are within the Fraser Valley and were affected by the floods)<ref>{{Cite journal|last=Liao|first=Enqi|date=May 24, 2024|title=Travel Behavior during the 2021 British Columbia Floods Using De-identified Network Mobility Data|url=doi.org/10.32866/001c.117422|journal=Resilience Findings}}</ref>. In the following weeks, travel between the cities slowly began to increase, but
=== Environmental Impacts ===

The floods severely degraded the Lower Fraser Valley's critical habitat, which is essential for Pacific salmon and sturgeon. Rapidly rising waters caused massive sediment movement which buried salmon spawning grounds and destroyed eggs. Scientists note that the full impact on salmon populations may not be known until their 2 to 5 year life cycles are complete in spawning season of 2026 <ref>{{Cite web|last=DFO|date=2022|title=Extreme environmental impacts on Pacific salmon|url=https://www.pac.dfo-mpo.gc.ca/pacific-smon-pacifique/environmental-impacts-environnementaux-eng.html|url-status=live|access-date=09 March 2026}}</ref>.

Excessive nutrients (nitrogen and phosphorus) washed into slow moving bodies of water, leading to eutrophication. This process depletes dissolved oxygen effectively suffocating fish and other aquatic organisms <ref>{{Cite web|last=Ross et al.|date=November 2022|title=A lake re-emerges: Analysis of contaminants in the Semá:th X̱ó:tsa (Sumas Lake) region following the BC floods of 2021|url=https://www.raincoast.org/reports/flood/|url-status=live|access-date=09 March 2026}}</ref>.

The death of over 670,000 farm animals created a biological hazard through an increase of immediate groundwater contamination and the spread of disease <ref name=":6">{{Cite web|last=Province of British Columbia|date=2024|title=Flood debris management projects|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects|url-status=live|access-date=09 March 2026}}</ref>. Crews eventually removed over 16,000 metric tons of natural and man-made debris (including 98 vehicles and 4 bridges) from provincial waterways to prevent further ecological blockages from occurring as a result of the floods <ref name=":6" />.
=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />. In addition to flood damage to farmers, the Insurance Bureau of Canada reported an estimated $9 billion Canadian dollars (CAD) in insured damages, contributing to the further economic impacts <ref>{{Cite web|last=S. Richards-Thomas, J. Déry, E. Stewart, M. Thériault,|first=Tamar, Stephen J. Déry, Ronald, Julie|date=12 June, 2024|title=Climatological context of the mid-November 2021 floods in the province of British Columbia, Canada|url=https://www.sciencedirect.com/science/article/pii/S2212094724000665|url-status=live|access-date=10 April, 2026}}</ref>. Power outages also contributed to further economic damage.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response and Recovery Efforts ==

The provincial government of British Columbia declared a state of emergency and implemented a variety of disaster responses in the event of BC's 2021 floods. This caused Canadian Governments of many levels to respond with recovery and evacuation plans as well as emergency response units to address damage to infrastructure, the environment, and the evacuation of affected communities . Initiatives from the provincial government focused on post-flood repair and clean up by implementing flood debris management programs to restore and improve waterways <ref name=":6" />.

Water quality assessments were conducted by researchers and the government to evaluate and record potential pollutants in the water within the Fraser River Valley area after the floods. Additionally, the research group wanted to determine if the flood event caused accelerated pollution of contaminants compared to average rainfalls to track changes in water composition, ensuring that contamination levels do not further worsen beyond expectations<ref name=":5" />.

Infrastructure of highways and railways where prioritized for repair from flood and landslide damage by the government as they were critical transportation and trade routes. Repair crews often had to reconstruct entire sections of highways due to erosion while reinforcing them to prevent similar events from happening in the future. These repairs reconnected the Lower Mainland with the rest of Canada, which reactivated many supply chains<ref name=":3" />.

[[File:Screenshot 2026-03-08 at 9.26.41 PM.png|thumb|340x340px|Minister Kelly Greene and Minister Lana Popham meet with Abbotsford Mayor Ross Siemens and technical experts to give the latest update on flood response in British Columbia. Following the update, Minister Greene and the Mayor toured areas impacted by the atmospheric river and the emergency operations centre. December 12, 2026. ]]

== Future Recommendations and Preventative Measures ==
Following the recovery efforts, several preventative measures were put into place in order to prevent further flooding across British Columbia's lower mainland - from upstream of Fraser Valley all the way down to the Pacific Ocean <ref name=":32">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. The most widespread measure used across this area is dikes, large engineered barriers intended to prevent flooding by either containing, or separating the water from the land. Despite a numerous dikes being in place, Principle Flood Management Engineer Monica Mannerström noted that a study found 87% of dikes to be "in less-than-fair condition" and that 71% simply wouldn't hold in the event of a flood, rendering them useless <ref name=":32" />.

Along with the dikes, a water pump system upgrade was deemed [[File:54989012923 95b4e84af5 o.jpg|thumb|Premier David Eby, Minister Kelly Greene, Minister Lana Popham and others visit Abbotsford on December 15, 2026. ]]

==References==

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-10T04:43:23Z

MaxForman: /* Introduction[1] */

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-10T03:37:24Z

MaxForman: /* History of the Sumas Prairie and its Colonization */

= Environmental and Social Impacts of the 2021 Flooding Season in Southern BC =
== Introduction<ref name=":4">{{Cite web|last=Finn et al.|date=02 June 2024|title=Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake|url=https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2024.1380083/full|url-status=live|access-date=08 March 2026}}</ref> ==
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
== History of the Sumas Prairie and its Colonization ==
The Sumas prairie has experienced extreme change to appear the way that it does today. Historically, the eastern part of the Sumas Prairie was occupied by Sumas Lake, before its eventual draining for agricultural purposes between 1920 and 1924. Farmers sought the fertile soil at the bottom of the lake<ref>{{Cite web|date=January 7, 2025|title=Sumas River and Canal|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects/sumas-river-and-canal|url-status=live|website=Government of British Columbia}}</ref>.

Historically, Sumas Lake saw much natural variability, which mainly was caused by the Lake's connection to the Fraser River, which is in turn connected to the Pacific Ocean. The water levels of the Fraser River typically rise in the summer due to snowmelt. This unpredictability in the Fraser directly translated to the Sumas Lake, with the water levels of the Lake seeing large changes in depth and size depending on the season, snowmelt, and even the Pacific tides<ref name=":7">{{Cite journal|last=Murton|first=James|date=January 2008|title=Creating Order: the Liberals, the Landowners, and the Draining of Sumas Lake, British Columbia|url=https://www.proquest.com/docview/216123962/fulltextPDF/D6152C190D6F41EBPQ/1?accountid=14656&sourcetype=Scholarly%20Journals|journal=Environmental History|via=ProQuest}}</ref>.

The Stó:lō people are an Indigenous group that have historically inhabited the Fraser Valley for at least 4,000 years. They had a deep connection to Sumas Lake, both for cultural purposes and for fishing. In 1858, the discovery of gold in the Fraser Valley meant that the Stó:lō were forced into reserves by James Douglas, British Columbia's governor<ref name=":7" />. In the 1970s, there began to be discussion and legislation surrounding diking the Sumas Lake. By 1920, the conversation had shifted towards draining the lake, with hopes of accessing the fertile soil at the bottom of the Sumas Lake and avoiding its unpredictable shifts. By June 26, 1924, the Sumas Lake was gone<ref name=":7" />. Today, the lake remains drained and is mostly covered by agricultural lands.

==Converging Factors and Causes of Flooding==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, BC's nature, and the citizens of British Columbia

=== Human Impacts ===

During the floods and the resulting landslides, five individuals were confirmed dead, with well over 3,000 residents forced out of their homes and evacuated in the Abbotsford area alone <ref name=":4" />. In the Sumas Prairie, the former Sumas Lake refilled, displacing thousands and destroying homes built on the historic lake bed<ref name=":4" />.

Floodwaters transported significant amounts of debris, sediment, and bacteria. E. coli counts at several locations, such as the Pitt Meadows Shoreline, exceeded Canadian Drinking Water Quality Guidelines (CDWQG) following sanitary sewer overflows <ref name=":5">{{Cite web|last=Minton et al.|date=June 2022|title=Water Quality Assessment of the Fraser River Following
the November 2021 Floods|url=https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/flood-response-and-the-environment/water-quality/water_quality_assessment_of_fraser_river_2021_floods.pdf|url-status=live|access-date=09 March 2026}}</ref>. Sanitary sewer overflows (SSOs) and the overflow of septic systems led to dangerous spikes in bacteria and other waterborne pathogens which pose risks to human health <ref name=":5" />.
=== Environmental Impacts ===

The floods severely degraded the Lower Fraser Valley's critical habitat, which is essential for Pacific salmon and sturgeon. Rapidly rising waters caused massive sediment movement which buried salmon spawning grounds and destroyed eggs. Scientists note that the full impact on salmon populations may not be known until their 2 to 5 year life cycles are complete in spawning season of 2026 <ref>{{Cite web|last=DFO|date=2022|title=Extreme environmental impacts on Pacific salmon|url=https://www.pac.dfo-mpo.gc.ca/pacific-smon-pacifique/environmental-impacts-environnementaux-eng.html|url-status=live|access-date=09 March 2026}}</ref>.

Excessive nutrients (nitrogen and phosphorus) washed into slow moving bodies of water, leading to eutrophication. This process depletes dissolved oxygen effectively suffocating fish and other aquatic organisms <ref>{{Cite web|last=Ross et al.|date=November 2022|title=A lake re-emerges: Analysis of contaminants in the Semá:th X̱ó:tsa (Sumas Lake) region following the BC floods of 2021|url=https://www.raincoast.org/reports/flood/|url-status=live|access-date=09 March 2026}}</ref>.

The death of over 670,000 farm animals created a biological hazard through an increase of immediate groundwater contamination and the spread of disease <ref name=":6">{{Cite web|last=Province of British Columbia|date=2024|title=Flood debris management projects|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects|url-status=live|access-date=09 March 2026}}</ref>. Crews eventually removed over 16,000 metric tons of natural and man-made debris (including 98 vehicles and 4 bridges) from provincial waterways to prevent further ecological blockages from occurring as a result of the floods <ref name=":6" />.
=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response and Recovery Efforts ==

The provincial government of British Columbia declared a state of emergency and implemented a variety of disaster responses in the event of BC's 2021 floods. This caused Canadian Governments of many levels to respond with recovery and evacuation plans as well as emergency response units to address damage to infrastructure, the environment, and the evacuation of affected communities . Initiatives from the provincial government focused on post-flood repair and clean up by implementing flood debris management programs to restore and improve waterways <ref name=":6" />.

Water quality assessments were conducted by researchers and the government to evaluate and record potential pollutants in the water within the Fraser River Valley area after the floods. Additionally, the research group wanted to determine if the flood event caused accelerated pollution of contaminants compared to average rainfalls to track changes in water composition, ensuring that contamination levels do not further worsen beyond expectations<ref name=":5" />.

Infrastructure of highways and railways where prioritized for repair from flood and landslide damage by the government as they were critical transportation and trade routes. Repair crews often had to reconstruct entire sections of highways due to erosion while reinforcing them to prevent similar events from happening in the future. These repairs reconnected the Lower Mainland with the rest of Canada, which reactivated many supply chains<ref name=":3" />.

[[File:Screenshot 2026-03-08 at 9.26.41 PM.png|thumb|340x340px|Minister Kelly Greene and Minister Lana Popham meet with Abbotsford Mayor Ross Siemens and technical experts to give the latest update on flood response in British Columbia. Following the update, Minister Greene and the Mayor toured areas impacted by the atmospheric river and the emergency operations centre. December 12, 2026. ]]

== Future Recommendations and Preventative Measures ==
Following the recovery efforts, several preventative measures were put into the place in order to prevent further flooding across British Columbia's lower mainland - from upstream of Fraser Valley all the way down to the Pacific Ocean <ref name=":32">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. The most widespread measure used across this area is dikes, large engineered barriers intended to prevent flooding by either containing, or separating the water from the land. Despite a numerous dikes being in place, Principle Flood Management Engineer Monica Mannerström noted that a study found 87% of dikes to be "in less-than-fair condition" and that 71% simply wouldn't hold in the event of a flood, rendering them useless <ref name=":32" />.

Along with the dikes, a water pump system upgrade was deemed [[File:54989012923 95b4e84af5 o.jpg|thumb|Premier David Eby, Minister Kelly Greene, Minister Lana Popham and others visit Abbotsford on December 15, 2026. ]]

==References==

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-09T19:11:43Z

MaxForman: /* History of the Sumas Prairie and its Colonization */

= Environmental and Social Impacts of the 2021 Flooding Season in Southern BC =
== Introduction<ref name=":4">{{Cite web|last=Finn et al.|date=02 June 2024|title=Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake|url=https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2024.1380083/full|url-status=live|access-date=08 March 2026}}</ref> ==
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
== History of the Sumas Prairie and its Colonization ==
The Sumas prairie has experienced extreme change to appear the way that it does today. Historically, the eastern part of the Sumas Prairie was occupied by Sumas Lake, before its eventual draining for agricultural purposes between 1920 and 1924. Farmers sought the fertile soil at the bottom of the lake<ref>{{Cite web|date=January 7, 2025|title=Sumas River and Canal|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects/sumas-river-and-canal|url-status=live|website=Government of British Columbia}}</ref>.

Historically, Sumas Lake saw much natural variability, which mainly was caused by the Lake's connection to the Fraser River, which is in turn connected to the Pacific Ocean. The water levels of the Fraser River typically rise in the summer due to snowmelt. This unpredictability in the Fraser directly translated to the Sumas Lake, with the water levels of the Lake seeing large changes in depth and size depending on the season, snowmelt, and even the Pacific tides<ref>{{Cite journal|last=Murton|first=James|date=January 2008|title=Creating Order: the Liberals, the Landowners, and the Draining of Sumas Lake, British Columbia|url=https://www.proquest.com/docview/216123962/fulltextPDF/D6152C190D6F41EBPQ/1?accountid=14656&sourcetype=Scholarly%20Journals|journal=Environmental History|via=ProQuest}}</ref>.

The Stó:lō people are an Indigenous group that have historically inhabited the Fraser Valley for at least 4,000 years. They had a deep connection to Sumas Lake, both for cultural purposes and for fishing and agriculture.

==Converging Factors and Causes of Flooding==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, BC's nature, and the citizens of British Columbia

=== Human Impacts ===

During the floods and the resulting landslides, five individuals were confirmed dead, with well over 3,000 residents forced out of their homes and evacuated in the Abbotsford area alone <ref name=":4" />. In the Sumas Prairie, the former Sumas Lake refilled, displacing thousands and destroying homes built on the historic lake bed<ref name=":4" />.

Floodwaters transported significant amounts of debris, sediment, and bacteria. E. coli counts at several locations, such as the Pitt Meadows Shoreline, exceeded Canadian Drinking Water Quality Guidelines (CDWQG) following sanitary sewer overflows <ref name=":5">{{Cite web|last=Minton et al.|date=June 2022|title=Water Quality Assessment of the Fraser River Following
the November 2021 Floods|url=https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/flood-response-and-the-environment/water-quality/water_quality_assessment_of_fraser_river_2021_floods.pdf|url-status=live|access-date=09 March 2026}}</ref>. Sanitary sewer overflows (SSOs) and the overflow of septic systems led to dangerous spikes in bacteria and other waterborne pathogens which pose risks to human health <ref name=":5" />.
=== Environmental Impacts ===

The floods severely degraded the Lower Fraser Valley's critical habitat, which is essential for Pacific salmon and sturgeon. Rapidly rising waters caused massive sediment movement which buried salmon spawning grounds and destroyed eggs. Scientists note that the full impact on salmon populations may not be known until their 2 to 5 year life cycles are complete in spawning season of 2026 <ref>{{Cite web|last=DFO|date=2022|title=Extreme environmental impacts on Pacific salmon|url=https://www.pac.dfo-mpo.gc.ca/pacific-smon-pacifique/environmental-impacts-environnementaux-eng.html|url-status=live|access-date=09 March 2026}}</ref>.

Excessive nutrients (nitrogen and phosphorus) washed into slow moving bodies of water, leading to eutrophication. This process depletes dissolved oxygen effectively suffocating fish and other aquatic organisms <ref>{{Cite web|last=Ross et al.|date=November 2022|title=A lake re-emerges: Analysis of contaminants in the Semá:th X̱ó:tsa (Sumas Lake) region following the BC floods of 2021|url=https://www.raincoast.org/reports/flood/|url-status=live|access-date=09 March 2026}}</ref>.

The death of over 670,000 farm animals created a biological hazard through an increase of immediate groundwater contamination and the spread of disease <ref name=":6">{{Cite web|last=Province of British Columbia|date=2024|title=Flood debris management projects|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects|url-status=live|access-date=09 March 2026}}</ref>. Crews eventually removed over 16,000 metric tons of natural and man-made debris (including 98 vehicles and 4 bridges) from provincial waterways to prevent further ecological blockages from occurring as a result of the floods <ref name=":6" />.
=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response and Recovery Efforts ==

The provincial government of British Columbia declared a state of emergency and implemented a variety of disaster responses in the event of BC's 2021 floods. This caused Canadian Governments of many levels to respond with recovery and evacuation plans as well as emergency response units to address damage to infrastructure, the environment, and the evacuation of affected communities . Initiatives from the provincial government focused on post-flood repair and clean up by implementing flood debris management programs to restore and improve waterways <ref name=":6" />.

Water quality assessments were conducted by researchers and the government to evaluate and record potential pollutants in the water within the Fraser River Valley area after the floods. Additionally, the research group wanted to determine if the flood event caused accelerated pollution of contaminants compared to average rainfalls to track changes in water composition, ensuring that contamination levels do not further worsen beyond expectations<ref name=":5" />.

Infrastructure of highways and railways where prioritized for repair from flood and landslide damage by the government as they were critical transportation and trade infrastructure. These repairs reconnected the Lower Mainland with the rest of Canada, which reactivated many supply chains<ref name=":3" />.

[[File:Screenshot 2026-03-08 at 9.26.41 PM.png|thumb|340x340px|Minister Kelly Greene and Minister Lana Popham meet with Abbotsford Mayor Ross Siemens and technical experts to give the latest update on flood response in British Columbia. Following the update, Minister Greene and the Mayor toured areas impacted by the atmospheric river and the emergency operations centre. December 12, 2026. ]]

== Future Recommendations and Preventative Measures ==
Following the recovery efforts, several preventative measures were put into the place in order to prevent further flooding across British Columbia's lower mainland - from upstream of Fraser Valley all the way down to the Pacific Ocean <ref name=":32">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. The most widespread measure used across this area is dikes, large engineered barriers intended to prevent flooding by either containing, or separating the water from the land. Despite a numerous dikes being in place, Principle Flood Management Engineer Monica Mannerström noted that a study found 87% of dikes to be "in less-than-fair condition" and that 71% simply wouldn't hold in the event of a flood, rendering them useless <ref name=":32" />.

Along with the dikes, a water pump system upgrade was deemed [[File:54989012923 95b4e84af5 o.jpg|thumb|Premier David Eby, Minister Kelly Greene, Minister Lana Popham and others visit Abbotsford on December 15, 2026. ]]

==References==

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-09T19:05:53Z

MaxForman: /* History of the Sumas Prairie and its Colonization */

= Environmental and Social Impacts of the 2021 Flooding Season in Southern BC =
== Introduction<ref name=":4">{{Cite web|last=Finn et al.|date=02 June 2024|title=Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake|url=https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2024.1380083/full|url-status=live|access-date=08 March 2026}}</ref> ==
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
== History of the Sumas Prairie and its Colonization ==
The Sumas prairie has experienced extreme change to appear the way that it does today. Historically, the eastern part of the Sumas Prairie was occupied by Sumas Lake, before its eventual draining for agricultural purposes between 1920 and 1924. Farmers sought the fertile soil at the bottom of the lake. <ref>{{Cite web|date=January 7, 2025|title=Sumas River and Canal|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects/sumas-river-and-canal|url-status=live|website=Government of British Columbia}}</ref>

Historically, Sumas Lake saw much natural variability, which mainly was caused by the Lake's connection to the Fraser River, which is in turn connected to the Pacific Ocean. The water levels of the Fraser River typically rise in the summer due to snowmelt. This unpredictability in the Fraser directly translated to the Sumas Lake, with the water levels of the Lake seeing large

The Stó:lō people are an Indigenous group that have historically inhabited the Fraser Valley for at least 4,000 years. They had a deep connection to Sumas Lake, both for cultural purposes and for fishing and agriculture.

==Converging Factors and Causes of Flooding==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, BC's nature, and the citizens of British Columbia

=== Human Impacts ===

During the floods and the resulting landslides, five individuals were confirmed dead, with well over 3,000 residents forced out of their homes and evacuated in the Abbotsford area alone <ref name=":4" />. In the Sumas Prairie, the former Sumas Lake refilled, displacing thousands and destroying homes built on the historic lake bed<ref name=":4" />.

Floodwaters transported significant amounts of debris, sediment, and bacteria. E. coli counts at several locations, such as the Pitt Meadows Shoreline, exceeded Canadian Drinking Water Quality Guidelines (CDWQG) following sanitary sewer overflows <ref name=":5">{{Cite web|last=Minton et al.|date=June 2022|title=Water Quality Assessment of the Fraser River Following
the November 2021 Floods|url=https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/flood-response-and-the-environment/water-quality/water_quality_assessment_of_fraser_river_2021_floods.pdf|url-status=live|access-date=09 March 2026}}</ref>. Sanitary sewer overflows (SSOs) and the overflow of septic systems led to dangerous spikes in bacteria and other waterborne pathogens which pose risks to human health <ref name=":5" />.
=== Environmental Impacts ===

The floods severely degraded the Lower Fraser Valley's critical habitat, which is essential for Pacific salmon and sturgeon. Rapidly rising waters caused massive sediment movement which buried salmon spawning grounds and destroyed eggs. Scientists note that the full impact on salmon populations may not be known until their 2 to 5 year life cycles are complete in spawning season of 2026 <ref>{{Cite web|last=DFO|date=2022|title=Extreme environmental impacts on Pacific salmon|url=https://www.pac.dfo-mpo.gc.ca/pacific-smon-pacifique/environmental-impacts-environnementaux-eng.html|url-status=live|access-date=09 March 2026}}</ref>.

Excessive nutrients (nitrogen and phosphorus) washed into slow moving bodies of water, leading to eutrophication. This process depletes dissolved oxygen effectively suffocating fish and other aquatic organisms <ref>{{Cite web|last=Ross et al.|date=November 2022|title=A lake re-emerges: Analysis of contaminants in the Semá:th X̱ó:tsa (Sumas Lake) region following the BC floods of 2021|url=https://www.raincoast.org/reports/flood/|url-status=live|access-date=09 March 2026}}</ref>.

The death of over 670,000 farm animals created a biological hazard through an increase of immediate groundwater contamination and the spread of disease <ref name=":6">{{Cite web|last=Province of British Columbia|date=2024|title=Flood debris management projects|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects|url-status=live|access-date=09 March 2026}}</ref>. Crews eventually removed over 16,000 metric tons of natural and man-made debris (including 98 vehicles and 4 bridges) from provincial waterways to prevent further ecological blockages from occurring as a result of the floods <ref name=":6" />.
=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response ==

The provincial government of British Columbia declared a state of emergency and implemented a variety of disaster responses in the event of BC's 2021 floods. This caused Canadian Governments of many levels to respond with recovery and evacuation plans as well as emergency response units to address damage to infrastructure, the environment, and the evacuation of affected communities . Initiatives from the provincial government focused on post-flood repair and clean up by implementing flood debris management programs to restore and improve waterways <ref name=":6" />.

Water quality assessments were conducted by researchers and the government to evaluate and record potential pollutants in the water within the Fraser River Valley area after the floods. Additionally, the research group wanted to determine if the flood event caused accelerated pollution of contaminants compared to average rainfalls <ref name=":5" />.

Infrastructure of highways and railways where prioritized for repair from flood and landslide damage by the government as they were critical transportation and trade infrastructure. These repairs reconnected the Lower Mainland with the rest of Canada, which reactivated many supply chains<ref name=":3" />.

[[File:Screenshot 2026-03-08 at 9.26.41 PM.png|thumb|340x340px|Minister Kelly Greene and Minister Lana Popham meet with Abbotsford Mayor Ross Siemens and technical experts to give the latest update on flood response in British Columbia. Following the update, Minister Greene and the Mayor toured areas impacted by the atmospheric river and the emergency operations centre. December 12, 2026. ]]

== Recovery and Long-Term Effects ==

The months following the flood consisted of constant recovery and construction efforts across the Fraser valley. Waterways were restored and assessed for any contaminants lingering the water so they may not affect local ecosystem as well as land and food supplies <ref name=":5" />. While flood debris management was implemented to improve river systems and clean up any damage or wreckage left after the flood <ref name=":6" />.

==Future Recommendations and Preventative Measures==
Following the recovery efforts, several preventative measures were put into the place in order to prevent further flooding across British Columbia's lower mainland - from upstream of Fraser Valley all the way down to the Pacific Ocean <ref name=":3" />. The most widespread measure used across this area is dikes, large engineered barriers intended to prevent flooding by either containing, or separating the water from the land. Despite a numerous dikes being in place, Principle Flood Management Engineer Monica Mannerström noted that a study found 87% of dikes to be in less than
[[File:54989012923 95b4e84af5 o.jpg|thumb|Premier David Eby, Minister Kelly Greene, Minister Lana Popham and others visit Abbotsford on December 15, 2026. ]]

==References==
Please use the Wikipedia reference style. Provide a citation for every sentence, statement, thought, or bit of data not your own, giving the author, year, AND page.
For dictionary references for English-language terms, I strongly recommend you use the Oxford English Dictionary. You can reference foreign-language sources but please also provide translations into English in the reference list.

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-09T18:33:42Z

MaxForman: /* History of Sumas Prairie and Nooksack Area */

= Environmental and Social Impacts of the 2021 Flooding Season in Southern BC =
== Introduction<ref name=":4">{{Cite web|last=Finn et al.|date=02 June 2024|title=Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake|url=https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2024.1380083/full|url-status=live|access-date=08 March 2026}}</ref> ==
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
== History of the Sumas Prairie and its Colonization ==
The Stó:lō are the Indigenous group that have historically inhabited the Fraser Valley for at least 4,000 years.

==Converging Factors and Causes of Flooding==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, BC's nature, and the citizens of British Columbia

=== Human Impacts ===

During the floods and the resulting landslides, five individuals were confirmed dead, with well over 3,000 residents forced out of their homes and evacuated in the Abbotsford area alone <ref name=":4" />. In the Sumas Prairie, the former Sumas Lake refilled, displacing thousands and destroying homes built on the historic lake bed<ref name=":4" />.

Floodwaters transported significant amounts of debris, sediment, and bacteria. E. coli counts at several locations, such as the Pitt Meadows Shoreline, exceeded Canadian Drinking Water Quality Guidelines (CDWQG) following sanitary sewer overflows <ref name=":5">{{Cite web|last=Minton et al.|date=June 2022|title=Water Quality Assessment of the Fraser River Following
the November 2021 Floods|url=https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/flood-response-and-the-environment/water-quality/water_quality_assessment_of_fraser_river_2021_floods.pdf|url-status=live|access-date=09 March 2026}}</ref>. Sanitary sewer overflows (SSOs) and the overflow of septic systems led to dangerous spikes in bacteria and other waterborne pathogens which pose risks to human health <ref name=":5" />.
=== Environmental Impacts ===

The floods severely degraded the Lower Fraser Valley's critical habitat, which is essential for Pacific salmon and sturgeon. Rapidly rising waters caused massive sediment movement which buried salmon spawning grounds and destroyed eggs. Scientists note that the full impact on salmon populations may not be known until their 2 to 5 year life cycles are complete in spawning season of 2026 <ref>{{Cite web|last=DFO|date=2022|title=Extreme environmental impacts on Pacific salmon|url=https://www.pac.dfo-mpo.gc.ca/pacific-smon-pacifique/environmental-impacts-environnementaux-eng.html|url-status=live|access-date=09 March 2026}}</ref>.

Excessive nutrients (nitrogen and phosphorus) washed into slow moving bodies of water, leading to eutrophication. This process depletes dissolved oxygen effectively suffocating fish and other aquatic organisms <ref>{{Cite web|last=Ross et al.|date=November 2022|title=A lake re-emerges: Analysis of contaminants in the Semá:th X̱ó:tsa (Sumas Lake) region following the BC floods of 2021|url=https://www.raincoast.org/reports/flood/|url-status=live|access-date=09 March 2026}}</ref>.

The death of over 670,000 farm animals created a biological hazard through an increase of immediate groundwater contamination and the spread of disease <ref name=":6">{{Cite web|last=Province of British Columbia|date=2024|title=Flood debris management projects|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects|url-status=live|access-date=09 March 2026}}</ref>. Crews eventually removed over 16,000 metric tons of natural and man-made debris (including 98 vehicles and 4 bridges) from provincial waterways to prevent further ecological blockages from occurring as a result of the floods <ref name=":6" />.
=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response ==

The provincial government of British Columbia declared a state of emergency and implemented a variety of disaster responses in the event of BC's 2021 floods. This caused Canadian Governments of many levels to respond with recovery and evacuation plans as well as emergency response units to address damage to infrastructure, the environment, and the evacuation of affected communities . Initiatives from the provincial government focused on post-flood repair and clean up by implementing flood debris management programs to restore and improve waterways <ref name=":6" />.

Water quality assessments were conducted by researchers and the government to evaluate and record potential pollutants in the water within the Fraser River Valley area after the floods. Additionally, the research group wanted to determine if the flood event caused accelerated pollution of contaminants compared to average rainfalls <ref name=":5" />.

Infrastructure of highways and railways where prioritized for repair from flood and landslide damage by the government as they were critical transportation and trade infrastructure. These repairs reconnected the Lower Mainland with the rest of Canada, which reactivated many supply chains<ref name=":3" />.

[[File:Screenshot 2026-03-08 at 9.26.41 PM.png|thumb|340x340px|Minister Kelly Greene and Minister Lana Popham meet with Abbotsford Mayor Ross Siemens and technical experts to give the latest update on flood response in British Columbia. Following the update, Minister Greene and the Mayor toured areas impacted by the atmospheric river and the emergency operations centre. December 12, 2026. ]]

== Recovery and Long-Term Effects ==

The months following the flood consisted of constant recovery and construction efforts across the Fraser valley. Waterways were restored and assessed for any contaminants lingering the water so they may not affect local ecosystem as well as land and food supplies <ref name=":5" />. While flood debris management was implemented to improve river systems and clean up any damage or wreckage left after the flood <ref name=":6" />.

==Future Recommendations and Preventative Measures==
You should conclude your Wiki paper by summarizing the topic, or some aspect of the topic.[[File:Crepuscular Rays in GGP.jpg|thumbnail|right|Images from [https://commons.wikimedia.org/wiki/Main_Page Wikimedia Commons] can be embedded easily.]]
==References==
Please use the Wikipedia reference style. Provide a citation for every sentence, statement, thought, or bit of data not your own, giving the author, year, AND page.
For dictionary references for English-language terms, I strongly recommend you use the Oxford English Dictionary. You can reference foreign-language sources but please also provide translations into English in the reference list.

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-09T18:11:33Z

MaxForman:

= Environmental and Social Impacts of the 2021 Flooding Season in Southern BC =
== Introduction<ref name=":4">{{Cite web|last=Finn et al.|date=02 June 2024|title=Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake|url=https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2024.1380083/full|url-status=live|access-date=08 March 2026}}</ref> ==
In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]

== History of Sumas Prairie and Nooksack Area ==

==Converging Factors and Causes of Flooding==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, BC's nature, and the citizens of British Columbia

=== Human Impacts ===

During the floods and the resulting landslides, five individuals were confirmed dead, with well over 3,000 residents forced out of their homes and evacuated in the Abbotsford area alone <ref name=":4" />. In the Sumas Prairie, the former Sumas Lake refilled, displacing thousands and destroying homes built on the historic lake bed<ref name=":4" />.

Floodwaters transported significant amounts of debris, sediment, and bacteria. E. coli counts at several locations, such as the Pitt Meadows Shoreline, exceeded Canadian Drinking Water Quality Guidelines (CDWQG) following sanitary sewer overflows <ref name=":5">{{Cite web|last=Minton et al.|date=June 2022|title=Water Quality Assessment of the Fraser River Following
the November 2021 Floods|url=https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/flood-response-and-the-environment/water-quality/water_quality_assessment_of_fraser_river_2021_floods.pdf|url-status=live|access-date=09 March 2026}}</ref>. Sanitary sewer overflows (SSOs) and the overflow of septic systems led to dangerous spikes in bacteria and other waterborne pathogens which pose risks to human health <ref name=":5" />.
=== Environmental Impacts ===

The floods severely degraded the Lower Fraser Valley's critical habitat, which is essential for Pacific salmon and sturgeon. Rapidly rising waters caused massive sediment movement which buried salmon spawning grounds and destroyed eggs. Scientists note that the full impact on salmon populations may not be known until their 2 to 5 year life cycles are complete in spawning season of 2026 <ref>{{Cite web|last=DFO|date=2022|title=Extreme environmental impacts on Pacific salmon|url=https://www.pac.dfo-mpo.gc.ca/pacific-smon-pacifique/environmental-impacts-environnementaux-eng.html|url-status=live|access-date=09 March 2026}}</ref>.

Excessive nutrients (nitrogen and phosphorus) washed into slow moving bodies of water, leading to eutrophication. This process depletes dissolved oxygen effectively suffocating fish and other aquatic organisms <ref>{{Cite web|last=Ross et al.|date=November 2022|title=A lake re-emerges: Analysis of contaminants in the Semá:th X̱ó:tsa (Sumas Lake) region following the BC floods of 2021|url=https://www.raincoast.org/reports/flood/|url-status=live|access-date=09 March 2026}}</ref>.

The death of over 670,000 farm animals created a biological hazard through an increase of immediate groundwater contamination and the spread of disease <ref name=":6">{{Cite web|last=Province of British Columbia|date=2024|title=Flood debris management projects|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects|url-status=live|access-date=09 March 2026}}</ref>. Crews eventually removed over 16,000 metric tons of natural and man-made debris (including 98 vehicles and 4 bridges) from provincial waterways to prevent further ecological blockages from occurring as a result of the floods <ref name=":6" />.
=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response ==

The provincial government of British Columbia declared a state of emergency and implemented a variety of disaster responses in the event of BC's 2021 floods. This caused Canadian Governments of many levels to respond with recovery and evacuation plans as well as emergency response units to address damage to infrastructure, the environment, and the evacuation of affected communities . Initiatives from the provincial government focused on post-flood repair and clean up by implementing flood debris management programs to restore and improve waterways <ref name=":6" />.

Water quality assessments were conducted by researchers and the government to evaluate and record potential pollutants in the water within the Fraser River Valley area after the floods. Additionally, the research group wanted to determine if the flood event caused accelerated pollution of contaminants compared to average rainfalls <ref name=":5" />.

Infrastructure of highways and railways where prioritized for repair from flood and landslide damage by the government as they were critical transportation and trade infrastructure. These repairs reconnected the Lower Mainland with the rest of Canada, which reactivated many supply chains<ref name=":3" />.

[[File:Screenshot 2026-03-08 at 9.26.41 PM.png|thumb|340x340px|Minister Kelly Greene and Minister Lana Popham meet with Abbotsford Mayor Ross Siemens and technical experts to give the latest update on flood response in British Columbia. Following the update, Minister Greene and the Mayor toured areas impacted by the atmospheric river and the emergency operations centre. December 12, 2026. ]]

== Recovery and Long-Term Effects ==

The months following the flood consisted of constant recovery and construction efforts across the Fraser valley. Waterways were restored and assessed for any contaminants lingering the water so they may not affect local ecosystem as well as land and food supplies <ref name=":5" />. While flood debris management was implemented to improve river systems and clean up any damage or wreckage left after the flood <ref name=":6" />.

==Future Recommendations and Preventative Measures==
You should conclude your Wiki paper by summarizing the topic, or some aspect of the topic.[[File:Crepuscular Rays in GGP.jpg|thumbnail|right|Images from [https://commons.wikimedia.org/wiki/Main_Page Wikimedia Commons] can be embedded easily.]]
==References==
Please use the Wikipedia reference style. Provide a citation for every sentence, statement, thought, or bit of data not your own, giving the author, year, AND page.
For dictionary references for English-language terms, I strongly recommend you use the Oxford English Dictionary. You can reference foreign-language sources but please also provide translations into English in the reference list.

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-09T18:04:16Z

MaxForman: /* Future Risk */

= Environmental and Social Impacts of the 2021 Flooding Season in Southern BC =
== Introduction<ref name=":4">{{Cite web|last=Finn et al.|date=02 June 2024|title=Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake|url=https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2024.1380083/full|url-status=live|access-date=08 March 2026}}</ref> ==
In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]

==Background (Should Change to History of Area + Factors/Causes)==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, BC's nature, and the citizens of British Columbia

=== Human Impacts ===

During the floods and the resulting landslides, five individuals were confirmed dead, with well over 3,000 residents forced out of their homes and evacuated in the Abbotsford area alone <ref name=":4" />. In the Sumas Prairie, the former Sumas Lake refilled, displacing thousands and destroying homes built on the historic lake bed<ref name=":4" />.

Floodwaters transported significant amounts of debris, sediment, and bacteria. E. coli counts at several locations, such as the Pitt Meadows Shoreline, exceeded Canadian Drinking Water Quality Guidelines (CDWQG) following sanitary sewer overflows <ref name=":5">{{Cite web|last=Minton et al.|date=June 2022|title=Water Quality Assessment of the Fraser River Following
the November 2021 Floods|url=https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/flood-response-and-the-environment/water-quality/water_quality_assessment_of_fraser_river_2021_floods.pdf|url-status=live|access-date=09 March 2026}}</ref>. Sanitary sewer overflows (SSOs) and the overflow of septic systems led to dangerous spikes in bacteria and other waterborne pathogens which pose risks to human health <ref name=":5" />.
=== Environmental Impacts ===

The floods severely degraded the Lower Fraser Valley's critical habitat, which is essential for Pacific salmon and sturgeon. Rapidly rising waters caused massive sediment movement which buried salmon spawning grounds and destroyed eggs. Scientists note that the full impact on salmon populations may not be known until their 2 to 5 year life cycles are complete in spawning season of 2026 <ref>{{Cite web|last=DFO|date=2022|title=Extreme environmental impacts on Pacific salmon|url=https://www.pac.dfo-mpo.gc.ca/pacific-smon-pacifique/environmental-impacts-environnementaux-eng.html|url-status=live|access-date=09 March 2026}}</ref>.

Excessive nutrients (nitrogen and phosphorus) washed into slow moving bodies of water, leading to eutrophication. This process depletes dissolved oxygen effectively suffocating fish and other aquatic organisms <ref>{{Cite web|last=Ross et al.|date=November 2022|title=A lake re-emerges: Analysis of contaminants in the Semá:th X̱ó:tsa (Sumas Lake) region following the BC floods of 2021|url=https://www.raincoast.org/reports/flood/|url-status=live|access-date=09 March 2026}}</ref>.

The death of over 670,000 farm animals created a biological hazard through an increase of immediate groundwater contamination and the spread of disease <ref name=":6">{{Cite web|last=Province of British Columbia|date=2024|title=Flood debris management projects|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects|url-status=live|access-date=09 March 2026}}</ref>. Crews eventually removed over 16,000 metric tons of natural and man-made debris (including 98 vehicles and 4 bridges) from provincial waterways to prevent further ecological blockages from occurring as a result of the floods <ref name=":6" />.
=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response ==

The provincial government of British Columbia declared a state of emergency and implemented a variety of disaster responses in the event of BC's 2021 floods. This caused Canadian Governments of many levels to respond with recovery and evacuation plans as well as emergency response units to address damage to infrastructure, the environment, and the evacuation of affected communities . Initiatives from the provincial government focused on post-flood repair and clean up by implementing flood debris management programs to restore and improve waterways <ref name=":6" />.

Water quality assessments were conducted by researchers and the government to evaluate and record potential pollutants in the water within the Fraser River Valley area after the floods. Additionally, the research group wanted to determine if the flood event caused accelerated pollution of contaminants compared to average rainfalls <ref name=":5" />.

Infrastructure of highways and railways where prioritized for repair from flood and landslide damage by the government as they were critical transportation and trade infrastructure. These repairs reconnected the Lower Mainland with the rest of Canada, which reactivated many supply chains<ref name=":3" />.

[[File:Screenshot 2026-03-08 at 9.26.41 PM.png|thumb|340x340px|Minister Kelly Greene and Minister Lana Popham meet with Abbotsford Mayor Ross Siemens and technical experts to give the latest update on flood response in British Columbia. Following the update, Minister Greene and the Mayor toured areas impacted by the atmospheric river and the emergency operations centre. December 12, 2026. ]]

== Recovery and Long-Term Effects ==

The months following the flood consisted of constant recovery and construction efforts across the Fraser valley. Waterways were restored and assessed for any contaminants lingering the water so they may not affect local ecosystem as well as land and food supplies <ref name=":5" />. While flood debris management was implemented to improve river systems and clean up any damage or wreckage left after the flood <ref name=":6" />.

==Future Recommendations and Preventative Measures==
You should conclude your Wiki paper by summarizing the topic, or some aspect of the topic.[[File:Crepuscular Rays in GGP.jpg|thumbnail|right|Images from [https://commons.wikimedia.org/wiki/Main_Page Wikimedia Commons] can be embedded easily.]]
==References==
Please use the Wikipedia reference style. Provide a citation for every sentence, statement, thought, or bit of data not your own, giving the author, year, AND page.
For dictionary references for English-language terms, I strongly recommend you use the Oxford English Dictionary. You can reference foreign-language sources but please also provide translations into English in the reference list.

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-09T18:03:58Z

MaxForman:

= Environmental and Social Impacts of the 2021 Flooding Season in Southern BC =
== Introduction<ref name=":4">{{Cite web|last=Finn et al.|date=02 June 2024|title=Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake|url=https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2024.1380083/full|url-status=live|access-date=08 March 2026}}</ref> ==
In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]

==Background (Should Change to History of Area + Factors/Causes)==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, BC's nature, and the citizens of British Columbia

=== Human Impacts ===

During the floods and the resulting landslides, five individuals were confirmed dead, with well over 3,000 residents forced out of their homes and evacuated in the Abbotsford area alone <ref name=":4" />. In the Sumas Prairie, the former Sumas Lake refilled, displacing thousands and destroying homes built on the historic lake bed<ref name=":4" />.

Floodwaters transported significant amounts of debris, sediment, and bacteria. E. coli counts at several locations, such as the Pitt Meadows Shoreline, exceeded Canadian Drinking Water Quality Guidelines (CDWQG) following sanitary sewer overflows <ref name=":5">{{Cite web|last=Minton et al.|date=June 2022|title=Water Quality Assessment of the Fraser River Following
the November 2021 Floods|url=https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/flood-response-and-the-environment/water-quality/water_quality_assessment_of_fraser_river_2021_floods.pdf|url-status=live|access-date=09 March 2026}}</ref>. Sanitary sewer overflows (SSOs) and the overflow of septic systems led to dangerous spikes in bacteria and other waterborne pathogens which pose risks to human health <ref name=":5" />.
=== Environmental Impacts ===

The floods severely degraded the Lower Fraser Valley's critical habitat, which is essential for Pacific salmon and sturgeon. Rapidly rising waters caused massive sediment movement which buried salmon spawning grounds and destroyed eggs. Scientists note that the full impact on salmon populations may not be known until their 2 to 5 year life cycles are complete in spawning season of 2026 <ref>{{Cite web|last=DFO|date=2022|title=Extreme environmental impacts on Pacific salmon|url=https://www.pac.dfo-mpo.gc.ca/pacific-smon-pacifique/environmental-impacts-environnementaux-eng.html|url-status=live|access-date=09 March 2026}}</ref>.

Excessive nutrients (nitrogen and phosphorus) washed into slow moving bodies of water, leading to eutrophication. This process depletes dissolved oxygen effectively suffocating fish and other aquatic organisms <ref>{{Cite web|last=Ross et al.|date=November 2022|title=A lake re-emerges: Analysis of contaminants in the Semá:th X̱ó:tsa (Sumas Lake) region following the BC floods of 2021|url=https://www.raincoast.org/reports/flood/|url-status=live|access-date=09 March 2026}}</ref>.

The death of over 670,000 farm animals created a biological hazard through an increase of immediate groundwater contamination and the spread of disease <ref name=":6">{{Cite web|last=Province of British Columbia|date=2024|title=Flood debris management projects|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects|url-status=live|access-date=09 March 2026}}</ref>. Crews eventually removed over 16,000 metric tons of natural and man-made debris (including 98 vehicles and 4 bridges) from provincial waterways to prevent further ecological blockages from occurring as a result of the floods <ref name=":6" />.
=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response ==

The provincial government of British Columbia declared a state of emergency and implemented a variety of disaster responses in the event of BC's 2021 floods. This caused Canadian Governments of many levels to respond with recovery and evacuation plans as well as emergency response units to address damage to infrastructure, the environment, and the evacuation of affected communities . Initiatives from the provincial government focused on post-flood repair and clean up by implementing flood debris management programs to restore and improve waterways <ref name=":6" />.

Water quality assessments were conducted by researchers and the government to evaluate and record potential pollutants in the water within the Fraser River Valley area after the floods. Additionally, the research group wanted to determine if the flood event caused accelerated pollution of contaminants compared to average rainfalls <ref name=":5" />.

Infrastructure of highways and railways where prioritized for repair from flood and landslide damage by the government as they were critical transportation and trade infrastructure. These repairs reconnected the Lower Mainland with the rest of Canada, which reactivated many supply chains<ref name=":3" />.

[[File:Screenshot 2026-03-08 at 9.26.41 PM.png|thumb|340x340px|Minister Kelly Greene and Minister Lana Popham meet with Abbotsford Mayor Ross Siemens and technical experts to give the latest update on flood response in British Columbia. Following the update, Minister Greene and the Mayor toured areas impacted by the atmospheric river and the emergency operations centre. December 12, 2026. ]]

== Recovery and Long-Term Effects ==

The months following the flood consisted of constant recovery and construction efforts across the Fraser valley. Waterways were restored and assessed for any contaminants lingering the water so they may not affect local ecosystem as well as land and food supplies <ref name=":5" />. While flood debris management was implemented to improve river systems and clean up any damage or wreckage left after the flood <ref name=":6" />.

== Future Risk ==

==Future Recommendations and Preventative Measures==
You should conclude your Wiki paper by summarizing the topic, or some aspect of the topic.[[File:Crepuscular Rays in GGP.jpg|thumbnail|right|Images from [https://commons.wikimedia.org/wiki/Main_Page Wikimedia Commons] can be embedded easily.]]
==References==
Please use the Wikipedia reference style. Provide a citation for every sentence, statement, thought, or bit of data not your own, giving the author, year, AND page.
For dictionary references for English-language terms, I strongly recommend you use the Oxford English Dictionary. You can reference foreign-language sources but please also provide translations into English in the reference list.

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-09T18:01:54Z

MaxForman: /* Environmental and Social Impacts of the 2021 Flooding Season in Southern BC */

= Environmental and Social Impacts of the 2021 Flooding Season in Southern BC =
== Introduction<ref name=":4">{{Cite web|last=Finn et al.|date=02 June 2024|title=Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake|url=https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2024.1380083/full|url-status=live|access-date=08 March 2026}}</ref> ==
In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]

==Background==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, BC's nature, and the citizens of British Columbia

=== Human Impacts ===

During the floods and the resulting landslides, five individuals were confirmed dead, with well over 3,000 residents forced out of their homes and evacuated in the Abbotsford area alone <ref name=":4" />. In the Sumas Prairie, the former Sumas Lake refilled, displacing thousands and destroying homes built on the historic lake bed<ref name=":4" />.

Floodwaters transported significant amounts of debris, sediment, and bacteria. E. coli counts at several locations, such as the Pitt Meadows Shoreline, exceeded Canadian Drinking Water Quality Guidelines (CDWQG) following sanitary sewer overflows <ref name=":5">{{Cite web|last=Minton et al.|date=June 2022|title=Water Quality Assessment of the Fraser River Following
the November 2021 Floods|url=https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/flood-response-and-the-environment/water-quality/water_quality_assessment_of_fraser_river_2021_floods.pdf|url-status=live|access-date=09 March 2026}}</ref>. Sanitary sewer overflows (SSOs) and the overflow of septic systems led to dangerous spikes in bacteria and other waterborne pathogens which pose risks to human health <ref name=":5" />.
=== Environmental Impacts ===

The floods severely degraded the Lower Fraser Valley's critical habitat, which is essential for Pacific salmon and sturgeon. Rapidly rising waters caused massive sediment movement which buried salmon spawning grounds and destroyed eggs. Scientists note that the full impact on salmon populations may not be known until their 2 to 5 year life cycles are complete in spawning season of 2026 <ref>{{Cite web|last=DFO|date=2022|title=Extreme environmental impacts on Pacific salmon|url=https://www.pac.dfo-mpo.gc.ca/pacific-smon-pacifique/environmental-impacts-environnementaux-eng.html|url-status=live|access-date=09 March 2026}}</ref>.

Excessive nutrients (nitrogen and phosphorus) washed into slow moving bodies of water, leading to eutrophication. This process depletes dissolved oxygen effectively suffocating fish and other aquatic organisms <ref>{{Cite web|last=Ross et al.|date=November 2022|title=A lake re-emerges: Analysis of contaminants in the Semá:th X̱ó:tsa (Sumas Lake) region following the BC floods of 2021|url=https://www.raincoast.org/reports/flood/|url-status=live|access-date=09 March 2026}}</ref>.

The death of over 670,000 farm animals created a biological hazard through an increase of immediate groundwater contamination and the spread of disease <ref name=":6">{{Cite web|last=Province of British Columbia|date=2024|title=Flood debris management projects|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects|url-status=live|access-date=09 March 2026}}</ref>. Crews eventually removed over 16,000 metric tons of natural and man-made debris (including 98 vehicles and 4 bridges) from provincial waterways to prevent further ecological blockages from occurring as a result of the floods <ref name=":6" />.
=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response ==

The provincial government of British Columbia declared a state of emergency and implemented a variety of disaster responses in the event of BC's 2021 floods. This caused Canadian Governments of many levels to respond with recovery and evacuation plans as well as emergency response units to address damage to infrastructure, the environment, and the evacuation of affected communities . Initiatives from the provincial government focused on post-flood repair and clean up by implementing flood debris management programs to restore and improve waterways <ref name=":6" />.

Water quality assessments were conducted by researchers and the government to evaluate and record potential pollutants in the water within the Fraser River Valley area after the floods. Additionally, the research group wanted to determine if the flood event caused accelerated pollution of contaminants compared to average rainfalls <ref name=":5" />.

Infrastructure of highways and railways where prioritized for repair from flood and landslide damage by the government as they were critical transportation and trade infrastructure. These repairs reconnected the Lower Mainland with the rest of Canada, which reactivated many supply chains<ref name=":3" />.

[[File:Screenshot 2026-03-08 at 9.26.41 PM.png|thumb|340x340px|Minister Kelly Greene and Minister Lana Popham meet with Abbotsford Mayor Ross Siemens and technical experts to give the latest update on flood response in British Columbia. Following the update, Minister Greene and the Mayor toured areas impacted by the atmospheric river and the emergency operations centre. December 12, 2026. ]]

== Recovery and Long-Term Effects ==

The months following the flood consisted of constant recovery and construction efforts across the Fraser valley. Waterways were restored and assessed for any contaminants lingering the water so they may not affect local ecosystem as well as land and food supplies <ref name=":5" />. While flood debris management was implemented to improve river systems and clean up any damage or wreckage left after the flood <ref name=":6" />.

=== Future Risk ===

==Conclusion==
You should conclude your Wiki paper by summarizing the topic, or some aspect of the topic.[[File:Crepuscular Rays in GGP.jpg|thumbnail|right|Images from [https://commons.wikimedia.org/wiki/Main_Page Wikimedia Commons] can be embedded easily.]]
==References==
Please use the Wikipedia reference style. Provide a citation for every sentence, statement, thought, or bit of data not your own, giving the author, year, AND page.
For dictionary references for English-language terms, I strongly recommend you use the Oxford English Dictionary. You can reference foreign-language sources but please also provide translations into English in the reference list.

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-04-09T17:40:53Z

MaxForman:

= Environmental and Social Impacts of the 2021 Flooding Season in Southern BC =
Include the scope/scale of the problem, intensity/frequency/severity of negative impacts, variables influencing those impacts and any other relevant information needed for understanding the issue.

== Introduction<ref name=":4">{{Cite web|last=Finn et al.|date=02 June 2024|title=Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake|url=https://www.frontiersin.org/journals/conservation-science/articles/10.3389/fcosc.2024.1380083/full|url-status=live|access-date=08 March 2026}}</ref> ==
In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]

==Background==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, BC's nature, and the citizens of British Columbia

=== Human Impacts ===

During the floods and the resulting landslides, five individuals were confirmed dead, with well over 3,000 residents forced out of their homes and evacuated in the Abbotsford area alone <ref name=":4" />. In the Sumas Prairie, the former Sumas Lake refilled, displacing thousands and destroying homes built on the historic lake bed<ref name=":4" />.

Floodwaters transported significant amounts of debris, sediment, and bacteria. E. coli counts at several locations, such as the Pitt Meadows Shoreline, exceeded Canadian Drinking Water Quality Guidelines (CDWQG) following sanitary sewer overflows <ref name=":5">{{Cite web|last=Minton et al.|date=June 2022|title=Water Quality Assessment of the Fraser River Following
the November 2021 Floods|url=https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/flood-response-and-the-environment/water-quality/water_quality_assessment_of_fraser_river_2021_floods.pdf|url-status=live|access-date=09 March 2026}}</ref>. Sanitary sewer overflows (SSOs) and the overflow of septic systems led to dangerous spikes in bacteria and other waterborne pathogens which pose risks to human health <ref name=":5" />.
=== Environmental Impacts ===

The floods severely degraded the Lower Fraser Valley's critical habitat, which is essential for Pacific salmon and sturgeon. Rapidly rising waters caused massive sediment movement which buried salmon spawning grounds and destroyed eggs. Scientists note that the full impact on salmon populations may not be known until their 2 to 5 year life cycles are complete in spawning season of 2026 <ref>{{Cite web|last=DFO|date=2022|title=Extreme environmental impacts on Pacific salmon|url=https://www.pac.dfo-mpo.gc.ca/pacific-smon-pacifique/environmental-impacts-environnementaux-eng.html|url-status=live|access-date=09 March 2026}}</ref>.

Excessive nutrients (nitrogen and phosphorus) washed into slow moving bodies of water, leading to eutrophication. This process depletes dissolved oxygen effectively suffocating fish and other aquatic organisms <ref>{{Cite web|last=Ross et al.|date=November 2022|title=A lake re-emerges: Analysis of contaminants in the Semá:th X̱ó:tsa (Sumas Lake) region following the BC floods of 2021|url=https://www.raincoast.org/reports/flood/|url-status=live|access-date=09 March 2026}}</ref>.

The death of over 670,000 farm animals created a biological hazard through an increase of immediate groundwater contamination and the spread of disease <ref name=":6">{{Cite web|last=Province of British Columbia|date=2024|title=Flood debris management projects|url=https://www2.gov.bc.ca/gov/content/environment/flood-projects|url-status=live|access-date=09 March 2026}}</ref>. Crews eventually removed over 16,000 metric tons of natural and man-made debris (including 98 vehicles and 4 bridges) from provincial waterways to prevent further ecological blockages from occurring as a result of the floods <ref name=":6" />.
=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response ==

The provincial government of British Columbia declared a state of emergency and implemented a variety of disaster responses in the event of BC's 2021 floods. This caused Canadian Governments of many levels to respond with recovery and evacuation plans as well as emergency response units to address damage to infrastructure, the environment, and the evacuation of affected communities . Initiatives from the provincial government focused on post-flood repair and clean up by implementing flood debris management programs to restore and improve waterways <ref name=":6" />.

Water quality assessments were conducted by researchers and the government to evaluate and record potential pollutants in the water within the Fraser River Valley area after the floods. Additionally, the research group wanted to determine if the flood event caused accelerated pollution of contaminants compared to average rainfalls <ref name=":5" />.

Infrastructure of highways and railways where prioritized for repair from flood and landslide damage by the government as they were critical transportation and trade infrastructure. These repairs reconnected the Lower Mainland with the rest of Canada, which reactivated many supply chains<ref name=":3" />.

[[File:Screenshot 2026-03-08 at 9.26.41 PM.png|thumb|340x340px|Minister Kelly Greene and Minister Lana Popham meet with Abbotsford Mayor Ross Siemens and technical experts to give the latest update on flood response in British Columbia. Following the update, Minister Greene and the Mayor toured areas impacted by the atmospheric river and the emergency operations centre. December 12, 2026. ]]

== Recovery and Long-Term Effects ==

The months following the flood consisted of constant recovery and construction efforts across the Fraser valley. Waterways were restored and assessed for any contaminants lingering the water so they may not affect local ecosystem as well as land and food supplies <ref name=":5" />. While flood debris management was implemented to improve river systems and clean up any damage or wreckage left after the flood <ref name=":6" />.

=== Future Risk ===

==Conclusion==
You should conclude your Wiki paper by summarizing the topic, or some aspect of the topic.[[File:Crepuscular Rays in GGP.jpg|thumbnail|right|Images from [https://commons.wikimedia.org/wiki/Main_Page Wikimedia Commons] can be embedded easily.]]
==References==
Please use the Wikipedia reference style. Provide a citation for every sentence, statement, thought, or bit of data not your own, giving the author, year, AND page.
For dictionary references for English-language terms, I strongly recommend you use the Oxford English Dictionary. You can reference foreign-language sources but please also provide translations into English in the reference list.

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-03-09T03:20:39Z

MaxForman:

Add your introduction here<ref>Sample Reference</ref>, covering general background information about the topic (e.g. location, duration).

Include the scope/scale of the problem, intensity/frequency/severity of negative impacts, variables influencing those impacts and any other relevant information needed for understanding the issue.

== Introduction ==
In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref name=":3">{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287?utm_source=chatgpt.com|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8?utm_source=chatgpt.com|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]

==Background==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, BC's nature, and the citizens of British Columbia.

=== Human Impacts ===

=== Environmental Impacts ===

=== Economic Impacts ===

The British Columbia provincial government estimated that BC's farmers lost approximately $285 million in flood-related damages <ref name=":3" />. This estimate took all of BC's various agricultural sectors into account, including how many acres of plants were lost, losses of cattle and homes on dairy farms, and the tens of thousands of hens lost in flooding. It is also key to highlight that the damage goes beyond the crops and cattle lost, as the farmland itself may suffer from long-term damage <ref name=":3" />.

The Trans-Canada highway, which spans from British Columbia to Newfoundland and Labrador, is Canada's main route for transporting goods across the country. The highway suffered immense damage during 2021's floods, interrupting the key transportation route through BC <ref name=":3" />. In addition, the flooding made transporting goods to and from the Port of Vancouver increasingly complicated. The Port of Vancouver is a key Canadian asset for international trade, and its disruption had negative effects on Canada's economy.

== Government Response ==

== Recovery and Long-Term Effects ==

=== Future Risk ===

==Conclusion==
You should conclude your Wiki paper by summarizing the topic, or some aspect of the topic.[[File:Crepuscular Rays in GGP.jpg|thumbnail|right|Images from [https://commons.wikimedia.org/wiki/Main_Page Wikimedia Commons] can be embedded easily.]]
==References==
Please use the Wikipedia reference style. Provide a citation for every sentence, statement, thought, or bit of data not your own, giving the author, year, AND page.
For dictionary references for English-language terms, I strongly recommend you use the Oxford English Dictionary. You can reference foreign-language sources but please also provide translations into English in the reference list.

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]

Course:CONS200/2026WT2/Environmental and social impacts of the 2021 flooding season in southern BC

2026-03-09T03:01:55Z

MaxForman:

Add your introduction here<ref>Sample Reference</ref>, covering general background information about the topic (e.g. location, duration).

Include the scope/scale of the problem, intensity/frequency/severity of negative impacts, variables influencing those impacts and any other relevant information needed for understanding the issue.

== Introduction ==
In November 2021, Southwestern BC experienced unprecedented rainfall that caused catastrophic flooding. The flooding caused widespread damage to infrastructure, agriculture, communities and ecosystems. The event resulted in damage to 1,000 farms, 15,000 hectares of land, 2.5 million livestock, and disrupting British Columbia’s road and railway infrastructure <ref>{{Cite web|last=Senate of Canada|date=October, 2022|title=Treading water: The impact of and response to the 2021 British Columbia floods|url=https://sencanada.ca/content/sen/committee/441/AGFO/reports/2022-10-27_B.C.Floods_AltText_e.pdf.|url-status=live|access-date=March 8, 2026}}</ref>. Further impacts such as floods and landslides resulted in the loss of at least five lives, cutting Vancouver off entirely from the rest of Canada by road and rail, making the event the costliest natural disaster in the province's history <ref name=":0">{{Cite web|last=Gillett et al.|date=27 April 2022|title=Human influence on the 2021 British Columbia floods|url=https://www.sciencedirect.com/science/article/pii/S2212094722000287?utm_source=chatgpt.com|url-status=live|archive-date=]|access-date=8 March 2026}}</ref>. The flooding was driven by a powerful atmospheric river that produced two days of intense rainfall, overwhelming regional drainage and flood control systems that were not designed for such extreme precipitation events. The intense rainfall the area experienced overwhelmed regional drainage and flood control systems that were not designed for such extreme precipitation events. Climate change likely increased the intensity and likelihood of the event <ref name=":1">{{Cite web|last=Environment and Climate Change Canada|date=March 2021|title=Human influence on the 2021 British Columbia floods|url=https://osdp-psdo.canada.ca/dp/en/search/metadata/ECCC-CURATED-1-FE331596-5442-4615-B477-2C46F07D12B8?utm_source=chatgpt.com|url-status=live|access-date=8 March 2026}}</ref>, highlighting the need for improved mitigation measures and informing policy changes aimed at reducing future flood risks.
[[File:51704524798 a634de57b5 o.jpg|thumb|Flood devastation over Abbotsford and Chilliwack BC, November 23, 2021.]]

==Background==
Atmospheric rivers are long and narrow filaments of concentrated water vapour, typically found in wetter west coast regions <ref name=":2">{{Cite web|last=Ralph et al.|date=01 April 2018|title=Defining “Atmospheric River”: How the Glossary of Meteorology Helped Resolve a Debate|url=https://journals.ametsoc.org/view/journals/bams/99/4/bams-d-17-0157.1.xml|url-status=live|access-date=8 March 2026}}</ref>. Atmospheric rivers often produce heavy rainfall when the moist air is forced upward by mountains or other rising air currents. <ref name=":2" />. These conditions contributed to the extreme rainfall and flooding in southern British Columbia in November 2021. Historically, westerly atmospheric river events of this magnitude are approximately one in ten year events in the region's current climate. Human-induced climate change has increased the likelihood of such events by at least 60% <ref name=":0" />, and studies indicate that the probability of extreme streamflow events in October–December has risen by an estimated 120–330% due to human influence <ref name=":1" />.

==Impacts ==
The flooding caused by the 2021 atmospheric rivers has severe impacts throughout British Columbia. These include impacts on British Columbia's major industries such as agriculture and the transportation of goods, BC's nature, and the citizens of British Columbia.

=== Human Impacts ===

=== Environmental Impacts ===

=== Economic Impacts ===

The British Columbia provincial government estimated

== Government Response ==

== Recovery and Long-Term Effects ==

=== Future Risk ===

==Conclusion==
You should conclude your Wiki paper by summarizing the topic, or some aspect of the topic.[[File:Crepuscular Rays in GGP.jpg|thumbnail|right|Images from [https://commons.wikimedia.org/wiki/Main_Page Wikimedia Commons] can be embedded easily.]]
==References==
Please use the Wikipedia reference style. Provide a citation for every sentence, statement, thought, or bit of data not your own, giving the author, year, AND page.
For dictionary references for English-language terms, I strongly recommend you use the Oxford English Dictionary. You can reference foreign-language sources but please also provide translations into English in the reference list.

'''Note:''' Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in [https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles Wikipedia: Writing better articles].<ref>En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].</ref>

<references/>

{{Projectbox CONS200
|names=
|share=no
}}

[[Category:Conservation]]