The 2021 Pacific Northwest floods were a series of floods that affected British Columbia, Canada, and parts of neighboring Washington state in the United States. The flooding and numerous mass wasting events were caused by a Pineapple Express, a type of atmospheric river, which brought heavy rain to parts of southern British Columbia and northwestern United States. The natural disaster prompted a state of emergency for the province of British Columbia.
Of particular concern in southern British Columbia was the severe short-term and long-term disruption of the transportation corridor linking the coastal city of Vancouver, Canada's largest port, to the Fraser Valley, the rest of British Columbia and the rest of Canada. The Fraser Valley, which is heavily populated, is responsible for most of the agricultural production in the province, with limited ability to feed farm animals in the absence of rail service. The Fraser Valley was particularly hard hit, as all major routes westward to Vancouver and eastward toward Alberta were impacted. Alternative routes into northern BC and southbound into Washington state are limited by the mountainous topography. The heavily used rail links of the Canadian National Railway (CN) and Canadian Pacific Railway (CP) were both disrupted, as well as all highways that connect the Lower Mainland with the rest of the province.
The British Columbia Minister of Public Safety, Mike Farnworth, issued a statement that the military deployment ended on December 17 after a month of aid. Conditions had improved enough for the reconstruction be managed by contractors, non-governmental organizations and a dedicated contingent from the region's wildland fire management service.
On December 10, the Insurance Bureau of Canada announced that the flooding cost at least $CDN 450 million in insured damage, making it the costliest natural disaster in British Columbia history. However, this amount did not include damage to infrastructure and other uninsured property. In particular, in the Sumas Prairie of the Abbotsford area, more than 600,000 farm animals perished in the floods. The reinsurer Aon issued a statement on December 17, 2021 claiming that the economic damage would amount to more than US$ 2 billion. According to the annual report of the NGO Christian Aid, issued December 26, the damages could amount up to US$ 7.5 billion.
Background
Several weather systems in early November contributed to record rainfall in southwestern British Columbia and the Pacific Northwest region of the United States. One of the systems produced a tornadic waterspout near Vancouver on November 6. Another system prompted two separate tornado warnings to be issued in Kitsap County, Washington, on November 9. Then the first deep low pressure system, which climatologists refer to as an atmospheric river, formed in the Pacific Ocean and moved into the coast on November 12. Two days later, a second atmospheric river following almost the same track moved into the coast. The U.S. National Weather Service issued flood warnings for Skagit and Whatcom counties, and high wind warnings for most of northwestern Washington. Three more atmospheric river events were scheduled to impact southern British Columbia and northwestern Washington state with the first arriving November 24, 2021 and the final event lasting through December 1, 2021.
Weather conditions In Hope, British Columbia, of rain fell from November 14 to 15, nearing the two-day record of set from November 9 to 10, 1990. In total, 20 rainfall records were broken across British Columbia. Hope, Agassiz, Malahat, Lillooet, and Abbotsford set new daily rainfall records on November 14, while both Hope and North Vancouver exceeded their average rainfall levels for all of November in a span of two days
Bellingham, Washington, which normally receives a monthly average of of rain for November, saw a new record of of rain from November 14 to 15 and new record of nearly of rain over 3 consecutive days.
Impacts The combined closures of sections of British Columbia Highway 1 (part of the Trans-Canada Highway), Highway 99, Highway 7, Highway 3, and the Coquihalla Highway (part of British Columbia Highway 5) had the effect of cutting off road traffic between Metro Vancouver and the rest of Canada. In response, the Canada Border Services Agency waived some border restrictions related to the COVID-19 pandemic so that Canadians could travel between Metro Vancouver and the rest of Canada through the United States.
Both the CNR and CPR rail lines were severed at multiple locations, with no rail connections between Kamloops and Vancouver. Via Rail passenger service on the Canadian, which uses CNR and CPR tracks, cancelled all trains travelling west of Winnipeg until December 12. The November 13 westbound train out of Toronto, already underway when the floods occurred, was halted at Winnipeg; passengers with final destinations west of Winnipeg were bussed or flown to their final destinations.
According to BC Hydro, at least 60,000 customers were left without electricity by the night of November 15 across B.C.
Squamish-Lillooet Regional District On November 15, multiple mudslides occurred which washed out multiple sections of Duffey Lake Road located 42 kilometres south of Lillooet. Multiple cars were caught up in the resulting debris field. Initially, one person was recovered deceased and four people were missing. The whole section of Duffey Lake Road from Mount Currie to Lillooet was closed due to the multiple mudslides. Five days later, Duffey Lake Road was re-opened to restricted traffic as ongoing search and rescue efforts led to three more people recovered as deceased. On November 20, Highway 99 re-opened to essential traffic only as crews continued to clear debris.
British Columbia Interior
Sections of Highway 1 and the Coquihalla Highway near Hope were washed away, along with a parallel railroad.
On the Coquihalla Highway, many bridges partly or completely collapsed. Near Hope, an entire section of the westbound side of the highway was washed out by the overflowing Coquihalla River. On November 18, the Government of British Columbia estimated that repairs for the Coquihalla Highway between Hope and Merritt would take months and that temporary Bailey bridges would be procured.
On November 15, Highway 3 and Highway 99 were also closed due to flooding and mudslides.
A track washout caused the derailment of a Canadian National Railway-operated freight train 25 kilometers north of Hope, British Columbia. No injuries were reported.
Highway 8 between Spences Bridge and Merritt suffered the most damage, as multiple sections of the highway were completely washed out and destroyed by flooding in the Nicola River where it caused almost all of the bridges that connected Collettville area to the rest of Merritt to collapse, and where it cut off access to small farming and Indigenous communities along the highway northwest of Merritt.
On November 15, all 7,000 residents of Merritt were evacuated after the city's sewage treatment plant flooded and failed after the Coldwater River burst its banks. Evacuees were instructed to go to either Kamloops or Kelowna.
Also on November 15, the community of Princeton, British Columbia declared a local state of emergency after the Tulameen and Similkameen rivers burst their banks and caused localized flooding. Natural gas service was disrupted until November 19, when gas crews began putting in new gas lines and repair some old ones. Highway 3 was re-opened the same day but restricted to essential traffic to minimize impact to repair and construction efforts underway.
Low-cost carrier Swoop announced that it would be instating flights between Abbotsford International Airport and Kelowna International Airport to aid in recovery efforts. These flights were available from November 22 to December 15, 2021.
Fraser Valley
On the north side of the Fraser River near Agassiz, Highway 7 was closed due to multiple mudslides that trapped over 300 people. The victims were airlifted to safety by 3 search and rescue helicopters from CFB Comox after spending more than two nights trapped inside vehicles. The Canada Task Force One Heavy Urban Search and Rescue Team was deployed to search the debris for missing persons.
Dozens more were rescued from rooftops and vehicles by volunteer search and rescue crews from several local groups led by Central Fraser Valley Search and Rescue.
Harbour Air offered special flights from Harrison Lake to Downtown Vancouver for evacuated residents who were unable to use Highway 7. Via Rail and Canadian National Railway operated an evacuation train from Hope to the Pacific Central Station in Vancouver. A section of Highway 7 between Agassiz and Hope reopened for limited westbound traffic on November 17.
Major regional public transit services in the area were negatively impacted by detours and closures of major thoroughfares. In the Central Fraser Valley, the 66 Fraser Valley Express which runs from Langley to Chilliwack via Highway 1 was shortened to run between Langley and Abbotsford due to the flooding of Highway 1. On December 1, West Coast Express commuter rail service was suspended between Mission City station and Maple Meadows station due to a mudslide on the CP tracks. In response, a replacement bus service was implemented to serve the affected stations during commuter rail operating hours.
Sumas Prairie The Sumas Prairie had been created in the early 1920s by draining Sumas Lake, but on November 16, overflow from the Sumas and Nooksack rivers refilled the lake, forcing the evacuation of 1100 homes in Abbotsford. The Sumas Prairie area was placed under catastrophic flood warning by that evening, with a substantial loss of farm animals, including cattle and chickens, predicted. The evacuation prompted the city of Abbotsford to open up an emergency evacuation centre located at the Abbotsford Recreation Centre.
On November 18, there remained a 100m long breach of the dikes by the Sumas River near the intersection of No. 4 Road and McDermott Road in Abbotsford. In order to stop the ongoing flooding of the Sumas Prairie, and enable repair of the affected sections of the dike, the original plan called for contracting crews and the Canadian military to construct a temporary 2.5 km long levee along Highway 1 near No. 4 Road. This levee construction would have resulted in the expropriation of 6 to 12 homes in the area. However, on the next day, an assessment of the Fraser River levels was made and it was discovered that the levels receded enough such that the levee construction and expropriation of homes was no longer necessary. Instead, the crews could now make direct repairs to the breaches in the dike without affecting any homes.
On November 28, the Nooksack River overtopped after recent rain events, forcing the evacuations of 90 homes in Huntingdon Village.
It is estimated that up to 630,000 animals died in the Sumas Prairie floods.
Metro Vancouver
In the city of Vancouver, the Burrard Bridge closed on November 15 after an unmoored barge threatened to collide with it. The bridge opened the following morning on November 16 after the barge grounded along the seawall. The barge later became a local attraction. Traffic in Richmond, British Columbia was heavily impacted by localized flooding such as on British Columbia Highway 99 near Westminster Highway, or Blundell Road. There was moderate damage in Richmond such as sink holes and destabilization of the dyke.
Despite strong winds, Vancouver International Airport reported only minor operational and traffic delays. Passengers travelling by air were advised to prepare for additional delays.
Vancouver Island