Frequently Asked Questions

Why is the structure being replaced? Why now?

• The dam was built in 1949 and is approaching 80 years old. Parts of it, like the concrete and metal from the late 1940s, were only expected to last 50–75 years. The dam is becoming harder to operate because it is sinking and shifting. This is making the structure crack, twist, and sink.
• Since 2017, WSA has been monitoring these problems closely. The uneven sinking is also causing the gates to jam when they try to open or close. Water has started flowing underneath the dam, creating bubbling in front of the gates. Without replacement, ongoing structural issues will continue to worsen and will make the structure very unsafe and potentially impossible to operate.

Where will the new dam be constructed?

• The new dam will be constructed immediately upstream of the existing structure.

Why not construct the new dam downstream of the existing dam structure?

• Building the new dam downstream was considered, but the idea was rejected for several reasons:
  • It would be too close to the highway bridge. The bridge affects water flow and would create problems for the control structure.
  • If the dam were built farther downstream to avoid the bridge, the lake would become bigger and could damage the bridge’s foundation.
  • By putting the new dam upstream, the old dam can be used as a barrier to keep water away from the construction area, making the work safer and easier.

How long will the project take to complete?

• The project is anticipated to start in the summer of 2026 and be completed in spring 2028.

What will the project cost?

• The final project cost will be published to the SaskTenders website after the public procurement to hire the general contractor closes and a contract is awarded.

Who operates the dam and how is it monitored?

• WSA staff (or a third-party contracted operator) operates the dam. Water levels are checked in real time by a monitoring station at Poplar Point, and staff work to keep water levels within the normal operating range.

Will the operation of the structure change during and after construction?

• WSA is not artificially lowering lake levels to facilitate construction. WSA will operate Cowan Lake within its typical operating range.
• The new nature-like fishway is designed to operate year-round, much like a natural creek or stream. The new dam will also have a gated pipe that can release extra water downstream when the fishway cannot manage all the flow. During spring runoff or floods, the large radial gates will be opened to safely pass higher water levels through the structure.

How will lake levels be managed during construction?

• A bypass channel will be dug through the Recreation Site, on the south side of the construction area, to help water move around the construction site. This will let the water that flows into the south end of Cowan Lake from the Big River travel safely around the work zone and continue into the Cowan River. During construction, water levels in Cowan Lake will be kept within the existing operating range. WSA does not plan to raise or lower the lake level while the project is underway.

What is the bypass channel for?

• Since Cowan Lake is on a natural river system, the bypass will be constructed to allow for natural river and riparian flows to proceed around the construction site and downstream.

What would happen if there was a flood during construction?

• The bypass channel is built with an armoured rock weir and equipped with four gated culverts. This allows normal flows to pass through the culverts while also allowing emergency flows to overtop the rock weir. The bypass channel can manage 43.7m3/s, which is equivalent to a 1:20 year flood event. A 1:20 year flood event is generally accepted in the dam industry as the size of diversion required for construction.

Will the cofferdam raise the water level in the Big River?

• The water coming from the Big River will be directed through the bypass channel so it can flow around the construction area and continue into the Cowan River. The water level in Cowan Lake will stay within its normal range, just like it has been in the past. The bypass channel will have gated pipes so WSA can control how much water leaves the lake.

How will the dam and water flow around the dam affect safety?

• A bright yellow floating boom will sit in front of the dam to keep ice, debris, boats, and swimmers away from fast‑moving water. It is positioned so that even during a major flood, water speeds stay low enough for someone to pull themselves to safety if needed. The boom is angled toward shore to make self‑rescue easier.
• The dam area will also be surrounded by a chain‑link fence to keep people out of hazardous areas. In addition, large safety signs—using standard warning symbols and colours—will be placed around the site to clearly alert the public to potential dangers.

Will the public be able to cross the new structure?

• The bridge deck on the structure is for WSA staff to use during regular operations and maintenance and will not be open to the public.

Will the Cowan Dam Recreation Site be closed during construction?

• Yes, from July 2026 to May 2028 as per the sign that was posted near the highway’s edge in May of 2024.
• See the image of the sign here.
• See the map of the Cowan Dam Recreation Site here.

Will the Cowan Dam Recreation Site re-open after construction? If so, will there be improvements made to the park?

• The Ministry of Parks, Culture and Sport (PCS) plans to reopen the Recreation Site in 2028 once the new dam is complete. WSA and PCS are teaming up to create a new Interpretive Deck along the shoreline downstream of the new dam with engaging information signs that will share the story of the dam’s history, the dam replacement project, and local fish and wildlife.
• PCS is also offering an opportunity for someone to lease and operate the Recreation Site. If you are interested, feel free to reach out at info@gov.sk.ca.

 How will the new dam affect campground access to Cowan Lake and the shoreline by the dam?

• Portions of the south shoreline will be fenced to separate the dam from the campground. This fencing will extend from the upstream safety boom to 23 metres downstream of the new dam. The 23-metre downstream fencing limit aligns with the Ministry of Environment restrictions about no angling within 23 meters (75 feet) of a dam.

Current bathroom facilities at the Recreation Site are not maintained. Will WSA have a role in seeing to the maintenance of the Recreation Site?

• WSA will not have a role in the future maintenance of the Recreation Site.

Will the boat launch be closed during construction?

• Yes, the boat launch will be closed to the public during the course of construction from July 1, 2026, to May 18, 2028, to safely facilitate the construction activities. The public will still be able to recreate on Cowan Lake outside of the construction site boundaries by utilizing an alternative boat launch such as the one in the Town of Big River.

Previously, we were able to park boats along the south shore, upstream of the existing dam’s boom. Will we still be able to do that?

• There will be a portion of the south upstream shore, upstream of the safety boom, which will be suitable for temporary landing of boats. There will also be a portage take-out in this location.

Can the water level in Cowan Lake be raised (6-12 inches) to accommodate our docks and boat lifts?

• No, the existing structure and the replacement structure are both designed to maintain the current water level of 476.35 metres. Any changes to that water level would require a change to the project license and would result in changes to the shoreline.

Will construction affect fish populations?

• Possibly. However, any spawning impacts are expected to be short‑term—limited to 2027—with conditions returning to normal after construction.

 How will the fishway and gates be used to pass water?

• The fishway is expected to run all year, as long as there is enough water from rain or snowmelt. It can release 2.7 m³/s of water on its own. If more flow is needed, a small gate can be opened to add, roughly, another 2 m³/s. If even more water needs to be released—above about 4.5 m³/s—the dam’s four spillway gates will be used. The spillway can manage large floods, up to 120 m³/s, which is the amount expected in a major 1‑in‑500‑year flood event.

How will the new fishway impact the lake?

• The new fishway is designed to work like a natural stream, using a series of small pools and gentle riffles to help fish move safely across the dam. It is built to accommodate even the slowest‑moving fish—often called “forage fish”—which are important food for larger species like Walleye, Pike, and Perch. By making it easier for all fish, especially these smaller forage species, to travel through the area, the fishway will help boost biodiversity in both the lake and the river. It will also allow downstream fish to move upstream and provide more feeding opportunities for game fish, which will help strengthen the overall health of the Cowan Lake fishery.

Was the bypass channel designed to convey fish?

• The bypass channel was designed to maintain control of the lake levels during construction. It would function for downstream fish passage and may provide upstream fish passage during periods of high flow release such as spring runoff. The diversion is only anticipated to be in use for one spring spawning season.

Will WSA stock Cowan Reservoir with walleye to offset the loss of the spring spawn in 2027?

• The Water Security Agency does not stock reservoirs; that responsibility lies with the Ministry of Environment. After consulting with the Ministry of Environment, WSA learned that there are currently no plans to stock Cowan Lake. However, the Ministry of Environment will be conducting a Fisheries Assessment in the summer of 2026 to evaluate the overall health of the Cowan Lake fishery.

Will I still be able to access the north shore for fishing?

• Portions of the north shore – including the fishway – will fall within WSA’s fenced-off area around the dam. However, people will still be able to access the shoreline on foot from the Highway 55 bridge.

Will the new dam impact the summer algae problems we sometimes experience on the lake?

• The new dam will not change the algae growth in the summer. Algae usually grows when lakes are shallow, warm, and have lots of nutrients. It also grows more when there is not enough rain or snowmelt to keep the water moving. At Cowan Lake, algae mostly show up in dry years because the lake does not get enough fresh water flowing through it.

What are turbidity curtains?

• Turbidity curtains—also called silt curtains or barriers—are floating barriers used during construction in or near water. Their job is to stop dirt and sediment from spreading into the lake or river. They have a float on top, a curtain that hangs down in the water, and a weight at the bottom to keep it in place. This creates a temporary wall in the water that helps protect fish and other aquatic life from pollution.

What will WSA do for environmental monitoring during and after construction? Is WSA open to partnerships for these activities?

• WSA will be keeping a close watch on the environment throughout the two years of construction. Some measures will include:
  • Water clarity will be checked regularly to ensure that the turbidity curtains are functioning properly.
  • Trained biologists will execute live fish salvages to return fish to the lake during dewatering activities.
  • Silt fencing and straw waddles will be used to control surface water.
  • All equipment will be fueled away from the site and parked on drip trays when not in use.
• Once construction wraps up, WSA will work to reestablish any vegetation that was disturbed by the project. This is typically done by planting a native grass seed mix, as determined in consultation with the Ministry of Parks, Culture and Sport.
• WSA’s Operation and Maintenance team will ensure that the fishway is working as designed.
• WSA is interested in having conversations on partnering for future environmental monitoring.

Did WSA execute an Environmental Impact Assessment?

• WSA worked with the Ministry of Environment’s assessment team and received written approval to do a self‑assessment for the project. Because the new dam will be built in the same place as the existing one and is on previously disturbed land that is classified as a Recreation Site, the project did not meet any of the triggers that would require a full environmental assessment.

Did WSA complete a Heritage Resource Assessment?

• In 2024, a Heritage Resource Impact Assessment (HRIA) was conducted as part of the early project work. During this assessment, a new archaeological site was found, including items like pottery, stone tools, and animal remains. After reviewing the findings and the previous impacts in the area, the Ministry of Parks, Culture and Sport determined that no further archaeological studies were needed due to the previous level of disturbance to the area and issued WSA a Clearance Letter confirming this.

Why didn’t WSA conduct a Provincial Duty to Consult?

• Before the project began, Water Security Agency, Ministry of Environment, and Ministry of Parks, Culture and Sport all completed Duty to Consult pre‑assessments. None of these assessments were triggered because the dam site is fully within a Provincial Recreation Site, which is considered occupied land.