High water mystery remains at Sylvan Lake

Sylvan Lake’s water levels are at a historic high but the cause remains elusive, suggests a research report.

Sylvan Lake’s water levels are at a historic high but the cause remains elusive, suggests a research report.

The assessment commissioned by the province notes there has been a trend to higher water levels since the 1960s.

“It is not clear if any particular event occurred that is causing the lake levels to steadily increase over the past 50 years,” says the report, which went to Sylvan Lake town council on Monday.

Rainfall measurements show a decreasing trend, so that is unlikely the cause.

Lake levels peaked on Aug. 11, 2011, at 937.31 metres, the highest level reached since records began in 1918. Levels dropped slightly this year to 937.17 metres.

The high water levels in 2011 are believed to have been caused by a cool, wet spring that reduced evaporation (evaporation is responsible for an estimated 90 to 95 per cent of water loss).

Groundwater in the spring-fed lake is also a significant factor.

The “sill” of the lake has gotten higher over time — likely through silting — but has remained relatively stable since the late 1970s, says the report. An outlet creek is functioning as intended and is not blocked.

Mayor Susan Samson said the research does not provide quick-fix solutions to high lake levels that have left the town’s beach almost entirely under water.

“It’s a very complex problem with no easy solutions and I think that’s what that document proved to me,” said Samson.

A number of options for tackling lake levels are outlined — and some dismissed — in the report.

Trying to limit the amount of water coming into the lake would be expensive and cause environmental problems when lake levels return to normal naturally.

Pumping out the lake is not considered economically viable given estimated costs of $5 million to $20 million for pumps.

Three options for changing outlet channels to increase flow are outlined.

However, there are risks with meddling with the channel.

“Any alteration of the outlet, with an intended purpose of affecting Sylvan Lake levels, is of concern from an environmental perspective because of the potential to affect water quality, fisheries, aquatic vegetation, shoreline vegetation, waterfowl, and other wildlife busing the lake or shoreline.”

The most ambitious, and costly, of the options is to create a control structure. A dam-like structure with stop-logs that could be removed when water levels are high could cost $1.7 million.

A roughly $100,000 option would involve upgrading an outlet channel and lowering the sill level of the lake to allow water to start flowing out at lower elevations. However, lake levels would continue to fluctuate.

The cheapest alternative would be a maintenance program for the outlet channel at a cost of $50,000, although it “will not likely have a significant impact on lake levels as the overall channel capacity does not change.”

Other options include creating buffers and erosion measures to protect against high water levels, without impacting them.

The report sums up by saying lake levels are “naturally high and part of the normal fluctuations between low and high water levels.”

However, trying to manage lake levels is not worth the trouble, the report suggests.

“Lake focus options such as shoreline protection and, in particular, natural buffers are the favoured options even though they do not control lake levels.”

Samson said the province does not intend to play a role in managing lake levels and provided the report to give the Sylvan Lake Management Committee the necessary background should it wish to do something.

Whether that happens will be up for discussion at the committee’s next meeting on Sept. 5.

Any changes to the lake outlet or to lower the sill of the lake would require provincial and federal approvals.

Whatever work is done, though, does not come with a guarantee that the lake will be significantly altered.

“The science isn’t really clear on how much we can really affect that creek,” Samson said.

The management committee is comprised of the Town of Sylvan Lake, Red Deer and Lacombe Counties and five summer villages.

pcowley@bprda.wpengine.com

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

Red Deer RCMP say a 30-year-old man faces sexual charges against a teen. (File photo by Advocate staff)
Innisfail RCMP arrest man following ‘lengthy pursuit’

Innisfail RCMP say a “lengthy pursuit” through a rural area ended with… Continue reading

Red Deer South MLA Jason Stephan speaks in the Alberta Legislature on Wednesday in this image from his Facebook page.
Red Deer MLA Jason Stephan sounds off on socialism in anti-lockdown speech

Red Deer-South MLA Jason Stephan has applauded his government’s COVID-19 response, saying… Continue reading

(Photo by Paul Cowley/ Advocate Staff)
Mask bylaws not popular in rural areas

Red Deer and Blackfalds bylaws requiring masks in public places kick in on Monday

A GoFundMe campaign to support a Stettler couple following a fire has raised more than $3,000. (Contributed photo)
Family pet dies in Stettler fire

GoFundMe page has raised more than $3K so far

Canadian Olympic gymnast and National Sport School alumni Kyle Shewfelt announces his retirement in Calgary, Thursday, May 21, 2009. Calgary's board of education will close the National Sport School that has produced Olympic and Paralympic champions for 26 years. THE CANADIAN PRESS/Jeff McIntosh
Calgary’s National Sport School to close, looks to join a different school division

Calgary’s National Sport School to close, looks to join a different school division

Canada's Erica Wiebe, left, celebrates after defeating Nigeria's Blessing Onyebuchi, right on the ground, to win Gold medal in women's FS 76Kg wrestling at the Commonwealth Games on Gold Coast, Australia, Thursday, April 12, 2018. THE CANADIAN PRESS/AP-Manish Swarup
Canada’s Olympic champion wrestler Erica Wiebe eyes return to competition

Canada’s Olympic champion wrestler Erica Wiebe eyes return to competition

Louisiana-Lafayette running back Elijah Mitchell (15) is tackled by Coastal Carolina linebacker Enock Makonzo (43) and safety Cameron Mitchell (49) during the first half of an NCAA football game in Lafayette, La., Wednesday, Oct. 14, 2020. It's already been a season to remember but Canadian Enock Makonzo and the Coastal Carolina Chanticleers will chase two more firsts Saturday. THE CANADIAN PRESS/AP-Paul Kieu
Canadian Enock Makonzo, Chanticleers chase Sun Belt East regular-season crown

Canadian Enock Makonzo, Chanticleers chase Sun Belt East regular-season crown

Atlanta United's Mo Adams, right, challenges Toronto FC's Alejandro Pozuelo during first half MLS soccer action in East Hartford, Conn., Sunday, Oct. 18, 2020. Toronto FC's Alejandro Pozuelo says he finished the season with an injured leg. THE CANADIAN PRESS/AP-Jessica Hill
Toronto FC ready to refocus on future as long, hard season comes to an end

Toronto FC ready to refocus on future as long, hard season comes to an end

Federal Health Minister Patty Hajdu and Vancouver Mayor Kennedy Stewart speak to the media during a visit to the Molson Overdose Prevention Site in Vancouver's Downtown Eastside, Thursday, January 16, 2020. City councillors in Vancouver voted unanimously this week to ask federal officials for an exemption to Canada's Controlled Drugs and Substances Act, a decision advocates hope will blaze a trail for the decriminalization of small amounts of illicit drugs for personal use in other municipalities. THE CANADIAN PRESS/Jonathan Hayward
Advocates aim to shape ‘Vancouver model’ for drug decriminalization

Advocates aim to shape ‘Vancouver model’ for drug decriminalization

Senator Murray Sinclair appears before the Senate Committee on Aboriginal Peoples in Ottawa, Tuesday, May 28, 2019. Sinclair is planning to leave the Senate early next year. THE CANADIAN PRESS/Fred Chartrand
Sen. Murray Sinclair, former head of TRC, set to leave the upper chamber next January

Sen. Murray Sinclair, former head of TRC, set to leave the upper chamber next January

Carolina De La Torre, right, owner of Arepas Ranch in Calgary, poses for a photo with her husband in this undated handout photo. The Venezuelan woman who believes she was used as part of Jason Kenney's argument not to lockdown restaurants in the province remembers her encounter with the premier as a lot less dramatic than he suggested. THE CANADIAN PRESS/HO, Carolina De La Torre *MANDATORY CREDIT*
‘No crying’: Venezuelan refugee Kenney cited says interaction was less dramatic

‘No crying’: Venezuelan refugee Kenney cited says interaction was less dramatic

Prime Minister Justin Trudeau listens to a question from a reporter during a bi-weekly news conference outside Rideau cottage in Ottawa, Friday, Nov. 27, 2020. THE CANADIAN PRESS/Adrian Wyld
Trudeau feels most Canadians could be vaccinated by September 2021

Trudeau feels most Canadians could be vaccinated by September 2021

Most Read