Nechako Reservoir

{{Use Canadian English|date=February 2026}} {{Infobox body of water | name = Nechako Reservoir | image = | caption = | image_bathymetry = | caption_bathymetry = | location = British Columbia | coords = {{coord|53|45|N|126|0|W|region:CA-BC_type:waterbody|display=inline,title}} | type = hydroelectric reservoir | inflow = Nechako River | outflow = penstock |pushpin_map=British Columbia | catchment = | basin_countries = Canada | length ={{convert|140|mi|abbr=on}} | width = | area = {{convert|890|km2|abbr=on}} | depth = | max-depth = {{convert|305|m|abbr=on}} | volume = | residence_time = | shore = | elevation = {{convert|2790|ft|abbr=on}} | islands = | sections = Northern arm (Ootsa Lake, Whitesail Lake, Whitesail Reach) and south arm (Eutsuk Lake, Natalkuz Lake, Chedakuz Arm, Knewstubb Lake, Tetachuck Lake) | cities = }} The '''Nechako Reservoir''', sometimes called the '''Ootsa Lake Reservoir''', is a hydroelectric reservoir in British Columbia, Canada that was formed by the Kenney Dam making a diversion of the Nechako River through a 16-km intake tunnel in the Kitimat Ranges of the Coast Mountains to the 890 MW Kemano Generating Station at sea level at Kemano to service the then-new Alcan aluminum smelter{{sfn|Heritage British Columbia|2009}} at Kitimat. When it was constructed on the Nechako River in 1952, it resulted in the relocation of over 75 families.{{sfn|Heritage British Columbia|2009}} It was one of the biggest reservoirs built in Canada until the completion of the Columbia Treaty Dams and the W.A.C. Bennett Dam that created Lake Williston. The water level may swing 20 feet between 2790 and 2800 feet.

The damming "linked the rivers and lakes of Ootsa, Intata, Whitesail, Chelaslie, Tetachuck, Tahtsa, Sinclair (Long Lake), Euchu Lake, and Natalkuz into the reservoir with a surface area of over 90,000 hectares."{{sfn|Heritage British Columbia|2009}} "The water of these lakes and rivers was diverted westward to the Pacific Ocean, instead of eastward to the Fraser River."{{sfn|Heritage British Columbia|2009}}

The creation of the reservoir flooded the series of lakes which typified the upper Nechako basin and in the process rendered the Quanchus Range, which lies between the north and south arms of the reservoir, a virtual island. The names of lakes amalgamated into the reservoir are perpetuated as names for the various stretches of water. The north arm includes Ootsa Lake, Whitesail Lake, and Whitesail Reach, the south arm Eutsuk Lake, Natalkuz Lake, Chedakuz Arm, Knewstubb Lake, Tetachuck Lake, and others. Because Ootsa Lake is the largest of the original lakes its name is sometimes used for the whole reservoir, though the official name remains Nechako Reservoir.

Tweedsmuir North Provincial Park and Protected Area and Entiako Provincial Park both border the reservoir.

==Impact==

===Cheslatta Dakelh (Carrier)===

For many generations, the shores of Cheslatta Lake were home to the Cheslatta Carrier Nation. The flooding of Nechako Canyon destroyed their traditional hunting and fishing grounds and their homes.{{sfn|Heritage British Columbia|2009}}

===Salvage archaeology=== In the late 1940s, University of British Columbia professor Charles Edward Borden shifted his attention toward urgent salvage archaeology in the Nechako Canyon after learning that ALCAN planned on flooding the Nechako Canyon to supply power for their smelter in Kitimat (known as Kemano I Project).{{sfn|Roy|2010|p=127}} In 1951 Borden and his protégé, anthropology student, Wilson Duff located over 130 sites of importance to Cheslatta T'en history. They conducted more intensive investigations prior to the flooding of the area.{{sfn|Roy|2010|p=127}} The damming triggered "devastating changes for First Nations communities whose traditional territories lay in their path, including the destruction of Aboriginal gravesites, territories, livelihoods, and archaeological sites."{{sfn|Roy|2010|p=127}} In 1957, Alcan opened the gate of the spillway to Skin's Lake desecrating Cheslatta graves, which came to public attention during the Royal Commission on Aboriginal Peoples.{{sfn|Roy|2010|p=128}}

==Kemano Completion Project== In the 1970s, Alcan proposed expanding the generating capacity at their Kemano Powerhouse by diverting more water from the Nechako Reservoir. At that time, it was envisioned that no additional dams would be required, and there would be no additional flooding. However, the project faced challenges and was ultimately canceled by the Provincial Government in 1995 due to significant environmental concerns related to the Nechako River.

A second power tunnel between the reservoir and the powerhouse was later completed as the '''Kemano T2 Project'''. Rio Tinto's board approved the project in December 2017.<ref name="RTT2Brochure">{{cite web |url=https://www.riotinto.com/can/-/media/content/documents/operations/bc-works/t2/rt-bc-works-t2-project-brochure.pdf |title=Kemano T2 Project brochure |website=Rio Tinto |access-date=19 April 2026 }}</ref> The project was intended to provide redundancy for the original tunnel and improve the long-term reliability of the power supply to the Kemano Powerhouse and Rio Tinto's BC Works smelter in Kitimat.<ref name="RTT2Brochure" /> Construction of the 16-kilometre tunnel was completed in May 2022; it produced its first megawatt of electricity in July 2022 and was commissioned on 1 December 2022.<ref name="RTKemano2022">{{cite web |url=https://www.riotinto.com/en/news/releases/2022/rio-tinto-completes-kemano-hydropower-project |title=Rio Tinto completes Kemano hydropower project |website=Rio Tinto |date=1 December 2022 |access-date=19 April 2026 }}</ref> The District of Kitimat lists the ''Rio Tinto Kemano T2 Project (2017–2022)'' as complete.<ref name="KitimatProjects">{{cite web |url=https://www.kitimat.ca/en/business-and-development/current-major-projects.aspx |title=Current Major Projects |website=District of Kitimat |access-date=19 April 2026 }}</ref>

==Climate== Tahtsa Lake is at the far western end of Nechako Reservoir and has a subarctic climate (Köppen ''Dfc''), with high levels of precipitation and snowfall. <div style="width:85%;"> {{Weather box |location = Tahtsa Lake West, BC (1981-2010):863m |metric first = yes |single line = yes |Jan record high C = 10.5 |Feb record high C = 13.9 |Mar record high C = 14.0 |Apr record high C = 21.1 |May record high C = 30.0 |Jun record high C = 28.3 |Jul record high C = 31.7 |Aug record high C = 33.0 |Sep record high C = 27.8 |Oct record high C = 22.0 |Nov record high C = 12.8 |Dec record high C = 10.6 |year record high C = |Jan high C = -2.3 |Feb high C = -0.7 |Mar high C = 3.4 |Apr high C = 7.0 |May high C = 11.1 |Jun high C = 14.6 |Jul high C = 17.6 |Aug high C = 17.8 |Sep high C = 13.9 |Oct high C = 6.8 |Nov high C = 0.7 |Dec high C = -1.9 |year high C = |Jan mean C = -5.5 |Feb mean C = -4.7 |Mar mean C = -1.5 |Apr mean C = 1.7 |May mean C = 5.2 |Jun mean C = 8.6 |Jul mean C = 11.8 |Aug mean C = 11.8 |Sep mean C = 8.4 |Oct mean C = 3.2 |Nov mean C = -2.2 |Dec mean C = -4.8 |year mean C = |Jan low C = -8.7 |Feb low C = -8.8 |Mar low C = -6.4 |Apr low C = -3.5 |May low C = -0.8 |Jun low C = 2.6 |Jul low C = 5.9 |Aug low C = 5.8 |Sep low C = 2.8 |Oct low C = -0.5 |Nov low C = -5.0 |Dec low C = -7.7 |year low C = |Jan record low C = -35.6 |Feb record low C = -35.0 |Mar record low C = -31.7 |Apr record low C = -19.4 |May record low C = -6.7 |Jun record low C = -2.0 |Jul record low C = -6.1 |Aug record low C = -6.1 |Sep record low C = -20.0 |Oct record low C = -26.0 |Nov record low C = -30.0 |Dec record low C = -32.2 |year record low C = |precipitation colour = green |Jan precipitation mm = 267.3 |Feb precipitation mm = 202.4 |Mar precipitation mm = 134.6 |Apr precipitation mm = 94.1 |May precipitation mm = 75.1 |Jun precipitation mm = 64.9 |Jul precipitation mm = 51.4 |Aug precipitation mm = 74.4 |Sep precipitation mm = 155.2 |Oct precipitation mm = 281.9 |Nov precipitation mm = 295.1 |Dec precipitation mm = 288.3 |year precipitation mm =

|Jan snow cm = 200.9 |Feb snow cm = 165.5 |Mar snow cm = 101.8 |Apr snow cm = 45.4 |May snow cm = 9.0 |Jun snow cm = 0.2 |Jul snow cm = 0.0 |Aug snow cm = 0.0 |Sep snow cm = 0.6 |Oct snow cm = 40.0 |Nov snow cm = 186.5 |Dec snow cm = 225.8 |year snow cm = |source 1 = Environment Canada<ref name= "climate">{{cite web |url = https://climate.weather.gc.ca/climate_normals/results_1981_2010_e.html?searchType=stnName&txtStationName=Tahtsa&searchMethod=contains&txtCentralLatMin=0&txtCentralLatSec=0&txtCentralLongMin=0&txtCentralLongSec=0&stnID=547&dispBack=1| title = Tahtsa Lake West, BC| work = Canadian Climate Normals 1981–2010| date = 25 September 2013| publisher = Environment Canada| language = English, French| accessdate = August 31, 2023}}</ref> |date=August 2023 }}</div>

Wistaria is on the northern shore of Nechako Reservoir, about 85km east of Tahtsa Lake. Wistaria also has a subarctic climate (Köppen ''Dfc''), but it receives far less precipitation and snowfall. <div style="width:85%;"> {{Weather box |location = Wistaria, BC (1981-2010): 863m |metric first = yes |single line = yes |Jan record high C = 11.1 |Feb record high C = 12.8 |Mar record high C = 18.3 |Apr record high C = 26.7 |May record high C = 35.6 |Jun record high C = 32.8 |Jul record high C = 36.1 |Aug record high C = 35.6 |Sep record high C = 33.9 |Oct record high C = 24.4 |Nov record high C = 18.0 |Dec record high C = 11.5 |year record high C = |Jan high C = -4.1 |Feb high C = -1.4 |Mar high C = 3.3 |Apr high C = 8.5 |May high C = 13.2 |Jun high C = 17.2 |Jul high C = 19.6 |Aug high C = 19.8 |Sep high C = 15.6 |Oct high C = 8.3 |Nov high C = 1.0 |Dec high C = -3.0 |year high C = |Jan mean C = -7.9 |Feb mean C = -6.2 |Mar mean C = -2.1 |Apr mean C = 2.7 |May mean C = 7.2 |Jun mean C = 11.2 |Jul mean C = 13.5 |Aug mean C = 13.4 |Sep mean C = 9.5 |Oct mean C = 4.0 |Nov mean C = -2.1 |Dec mean C = -6.3 |year mean C = |Jan low C = -11.6 |Feb low C = -11.1 |Mar low C = -7.6 |Apr low C = -3.1 |May low C = 1.1 |Jun low C = 5.2 |Jul low C = 7.4 |Aug low C = 6.9 |Sep low C = 3.5 |Oct low C = -0.4 |Nov low C = -5.2 |Dec low C = -9.5 |year low C = |Jan record low C = -43.9 |Feb record low C = -40.6 |Mar record low C = -36.1 |Apr record low C = -25.6 |May record low C = -9.4 |Jun record low C = -4.4 |Jul record low C = -2.8 |Aug record low C = -3.3 |Sep record low C = -10.0 |Oct record low C = -23.5 |Nov record low C = -35.5 |Dec record low C = -41.7 |year record low C = |precipitation colour = green |Jan precipitation mm = 38.5 |Feb precipitation mm = 25.5 |Mar precipitation mm = 20.5 |Apr precipitation mm = 16.7 |May precipitation mm = 32.3 |Jun precipitation mm = 54.0 |Jul precipitation mm = 42.3 |Aug precipitation mm = 38.0 |Sep precipitation mm = 41.4 |Oct precipitation mm = 40.3 |Nov precipitation mm = 43.7 |Dec precipitation mm = 39.5 |year precipitation mm =

|Jan snow cm = 32.5 |Feb snow cm = 23.0 |Mar snow cm = 18.8 |Apr snow cm = 6.1 |May snow cm = 2.5 |Jun snow cm = 0.0 |Jul snow cm = 0.0 |Aug snow cm = 0.0 |Sep snow cm = 0.1 |Oct snow cm = 9.4 |Nov snow cm = 30.2 |Dec snow cm = 34.8 |year snow cm = |source 1 = Environment Canada<ref>{{cite web |url = https://climate.weather.gc.ca/climate_normals/results_1981_2010_e.html?searchType=stnProx&txtRadius=25&optProxType=station&coordsStn=53.8725%7C-125.870278%7CTAKYSIE+LAKE&txtCentralLatMin=0&txtCentralLatSec=0&txtCentralLongMin=0&txtCentralLongSec=0&stnID=555&dispBack=0| title = Wistaria, BC| work = Canadian Climate Normals 1981–2010| date = 31 October 2011| publisher = Environment Canada| language = English, French| accessdate = August 31, 2023}}</ref> |date=August 2023 }}</div>

==Citations== {{reflist}}

==References== *{{BCGNIS|9151|Nechako Reservoir}} *{{citation|first=Bev|last=Christensen|title=Too Good to be True: Alcan's Kemano Completion Project|publisher=Talonbooks|year=1995}} *{{citation|url=http://www.heritagebcstops.com/north-by-northwest-tour/ootsa-lake-nechako-reservoir|work=Heritage British Columbia|year=2009|title=Ootsa Lake-Nechako Reservoir|ref={{sfnref|Heritage British Columbia|2009}}|access-date=2013-12-04|archive-date=2013-10-30|archive-url=https://web.archive.org/web/20131030054115/http://www.heritagebcstops.com/north-by-northwest-tour/ootsa-lake-nechako-reservoir|url-status=dead}} *{{citation|url=https://books.google.com/books?id=diEDAAAAMBAJ&q=popular+science+1951+Kemano&pg=PA98|title=Engineers Invade Another Wilderness - Huge Canadian Power Project Marks 20th Century Frontier Boom|first=Richard|last=Neuberger|year=1951|publisher=Popular Science|access-date=3 December 2013|ref={{sfnref|Neuberger|2009}}}} Detailed and illustrated Popular Science article on the Kemano Hydro Project.\ *{{citation|title=These Mysterious People Shaping History and Archaeology in a Northwest Coast Community|url=http://www.mqup.ca/these-mysterious-people-products-9780773537217.php?page_id=46#sthash.SiWRcfyK.dpuf|publisher=McGill/Queen's University Press|pages=240|isbn=9780773537217|date=October 2010|first=Susan|last=Roy}} *{{citation|first=Bev|last=Christensen|title=Too Good to be True: Alcan's Kemano Completion Project|publisher=Talonbooks|year=1995}}

==External links== *{{citation|url=https://books.google.com/books?id=diEDAAAAMBAJ&q=popular+science+1951+Kemano&pg=PA98|title=Engineers Invade Another Wilderness - Huge Canadian Power Project Marks 20th Century Frontier Boom|first=Richard|last=Neuberger|year=1951|publisher=Popular Science|ref={{sfnref|Neuberger|2009}}}} Detailed and illustrated Popular Science article on the Kemano Hydro Project

Category:Reservoirs in British Columbia Category:Nechako Country Category:Range 4 Coast Land District