In 1906, the city of Saskatoon in Saskatchewan, Canada, built its original water treatment plant at Avenue H and 11th St. Since then, the city has implemented many improvements at the plant to provide residents with safe and clean drinking water.
Today, the water treatment plant employs a conventional treatment process including coagulation, sedimentation, filtration and chemical addition for taste and odor control, hardness control, fluoridation and disinfection. The plant has a capacity of 70 mgd, providing drinking water to more than 213,000 residents as well as commercial and industrial clients.
With a growing population, increasing water demand and increasingly stringent standards for water quality, the city has initiated a water supply and treatment plant upgrade and expansion program. In addition to meeting future water demand and water quality standards, the $130-million upgrade and expansion program will help extend the life of the plant for another 25 years.
As part of this expansion program, the city retained Associated Engineering to complete modeling and design, and provide construction services for a new raw water intake and pump station.
Upstream location
Currently, the city draws raw water from the South Saskatchewan River through a shared intake at SaskPower’s Queen Elizabeth Power Station, located about a mile upstream of the water treatment plant. Based on an intake feasibility study and the results of investigations during pre-design, a new intake and pump station were recommended upstream of the existing facility. The upstream location offers greater reliability and security, and increases the raw water intake capacity to 112 mgd.
“In siting the facility, we had to ensure the new intake would be hydraulically efficient and reliable, which was a challenge as the intake location is in relatively shallow waters,” said Bert Munro, project manager. “We also had to comply with the Department of Fisheries and Oceans’ (DFO) recommendations for fish screening. Land acquisition and the potential to affect flow to the existing intakes were also factors in the selection.”
The conceptual design includes an intake structure located at the tip of a man-made spur extending to the middle of the river. Twinned pipelines will run under the riverbed, connecting the intake to a pump station on the opposite bank. From the pump station, twin transmission mains will tie into the existing water supply main to the water treatment plant.
In keeping with the DFO’s fish protection requirements, inclined fish screens will be located at the intake structure with adequate screen area to provide very low approach velocities, reducing the chance of fish entrainment.
Construction of the intake and pump station is currently underway.