Lakes and Rivers

Water Conveyance and Flood Controls


Boundary to Rafferty Diversion Channel

To maximize flood control benefits associated with the Rafferty-Alameda Project, a 10.9 km long diversion canal was constructed from Boundary Reservoir to Rafferty Reservoir. This canal affords the ability to divert surplus flows in Long Creek which can not be stored in Boundary Reservoir, to Rafferty Reservoir. In addition to enhancing flood control benefits, such diversions also assist in stabilizing Rafferty Reservoir levels.

Although the nameplate capacity of the diversion channel is 60 m3/s, diversions in excess of 45 m3/s cause excessive erosion to the rock chute drop structure discharging into Rafferty Reservoir. The Water Security Agency is wholly responsible for the repair of the diversion channel.

Craven to Last Mountain Lake

Following the 0.46 m raising of Highway No. 20 near Craven in 1978, a 1.0 km long diversion channel was constructed the same year between the river and Last Mountain Lake Creek to restore the natural flow split between Last Mountain Lake and the river downstream of Craven. In the early 1980's, a further 5.5 km of conveyance improvements were constructed along Last Mountain Lake Creek to enhance operation management capabilities of the Qu'Appelle System.

Craven Flood Control Project

The Craven Flood Control Project, encompassing the construction of 1.9 km of improved channel and associated dyking along Last Mountain Lake Creek, was undertaken in the 1971. Pursuant to an agreement entered into between the Village and Sask Water in 1993, the Water Security Agency is fully responsible for the channel improvements. The Water Security Agency is also committed to sharing the costs of maintaining the flood control dykes in accordance with the Water Control Program in effect at the time of maintenance.

Craven to Katepwa Lake Outlet

Over an 11 year period extending from 1978 to 1988, extensive channel improvements were constructed between Craven and a location 7.4 km below Katepwa Lake. In total, 54.3 km of channel improvements were constructed along the Qu'Appelle River and its principal tributaries. The Water Security Agency is wholly responsible for these works.

The primary objective of the works was to upgrade the natural conveyance capacity to14.16 m3/s (500 cfs). Although a number of contemplated channel improvements between Highway No. 6 and Craven were not constructed, significantly greater operational flexibility resulted from construction that did occur.

Craven to Hwy No. 6 - Ditch Sections 1D to 3D 1.4 km
Hwy No. 6 to Pasqua Lake - Ditch Sections 1A, 2A, 2A', 3A & 1L 43.2 km
Echo Lake to Mission Lake - Ditch Sections 1E & 2E 0.6 km
Mission Lake to Katepwa Lake - Ditch Section 1M 1.0 km
Katepwa Lake Outlet - Ditch Section 1K, 1K1, 1K2, & 1K3 8.1 km

Emma Lake Diversion Channel

The Water Security Agency owns and operates a pump station on Anglin Lake as well as an approximate 10 km long water supply canal which discharges into Emma Lake. Via a further short reach of improved channel, the latter lake in turn feeds Christopher Lake. Diversions are made from Anglin Lake during the open water season to stabilize the levels of Emma and Christopher Lakes, both of which are used extensively for recreational purposes.

Lumsden Flood Control Channel

Following the 1974 flood of record in the Qu'Appelle River System, the flood control channel and associated dyking through the Town of Lumsden were upgraded to accommodate the 1 in 500 year flood event (550 m3/s). The flood control channel extended 1.74 km upstream from the Highway No. 11 bridges to the western portion of the town. Flood control dykes were constructed along both sides of the flood channel and tie into the valley side slopes upstream and downstream of the town site. In 1999, the flood control channel was extended a further 525 m upstream given that erosion of the natural river channel was threatening the stability of the adjacent flood control dykes.

Per agreement with the Town, the Water Security Agency is wholly responsible for the maintenance and repair of the flood control channel, and also covers 50 per cent of the cost to maintain and repair the flood control dykes and appurtenant structures.

Craven Flood Control Project

The Craven Flood Control Project, encompassing the construction of 1.9 km of improved channel and associated dyking along Last Mountain Lake Creek, was undertaken in the 1971. Pursuant to an agreement entered into between the Village and Sask Water in 1993, the Water Security Agency is fully responsible for the channel improvements. The Water Security Agency is also committed to sharing the costs of maintaining the flood control dykes in accordance with the Water Control Program in effect at the time of maintenance.

Souris River Channel Improvements

As part of the Rafferty-Alameda Project, conveyance improvements were constructed along 9.1 km of the Souris River between Rafferty Dam and the Woodlawn Park Weir (east of the City of Estevan). The channel design flow was 14.16 m3/s (500 cfs). The Water Security Agency is wholly responsible for the maintenance of the improved channel.

Tantallon Flood Control Channel

Flood control works including 0.75 km of channel improvements and 1.4 km of dykes were constructed at the Village of Tantallon in 1975. The works were designed to afford flood protection up to 28.3 m3/s which, at the time, was estimated to be the 1 in 100 year flood event. Pursuant to a flood protection works agreement entered into between the Village and the Province, the Village is wholly responsible for the maintenance of the dyking system including drains. The the Water Security Agency is wholly responsible for maintaining the channel.

Upper Qu'Appelle Channel

The Upper Qu'Appelle Channel starts at the Qu'Appelle River Dam and extends 35 km downstream, terminating approximately 7.5 km downstream of Eyebrow Lake. The natural river channel runs a further 62 km before discharging into Buffalo Pound Lake.

The Channel was constructed during the mid and late 1960's and is critical to the economic and social well being of the Province. It supplies water to approximately 25 per cent of the population including the cities of Regina and Moose Jaw, a number of industries including Saskferco and Mosaic Potash at Belle Plaine, and agricultural irrigation both within and outside the Qu'Appelle Valley. The channel is also used to stabilize downstream lake levels.

Although the design capacity of the channel was 14 m3/s, prolific weed growth during the peak use months of July and August now often restrict deliveries to 6 m3/s or less. The channel has also suffered substantial bank erosion and silt deposition along much of its length. The Water Security Agency is wholly responsible for the constructed channel.

In December 2008, the Water Security Agency engaged the consulting firm AECOM to evaluate options to convey greater quantities of water from Lake Diefenbaker to Buffalo Pound Lake. This evaluation was initiated in response to potential development of significant new water demands on Buffalo Pound Lake such as new and expanding potash mines, a polygeneration plant, increased municipal demands, and potential irrigation developments both above and below Buffalo Pound Lake. The following slide presentation outlines AECOM’s findings.