McDonald Lake, also known as Rafferty Reservoir, is a reservoir in south-east Saskatchewan, Canada.[2] It was created when the Rafferty Dam was built on the Souris River in 1994. Before the dam was built that flooded the Souris Valley, McDonald Lake was a small lake and marsh on the valley floor adjacent to the Souris River.

McDonald Lake
Rafferty Reservoir
McDonald Lake as seen from the ISS
McDonald Lake Show map of Canada McDonald Lake Show map of Saskatchewan
Coordinates	49.194°N 103.238°W / 49.194; -103.238
Type	Reservoir
Primary inflows	Souris River, Jewell Creek, and a 10-kilometre diversion channel connecting Boundary and Rafferty Reservoirs, which allows water to be diverted from Boundary Reservoir into McDonald Lake.
Primary outflows	Souris River
Catchment area	2,448 km2 (945 sq mi)
Managing agency	The Saskatchewan Water Security Agency
Built	July 1, 1991 (1991-07-01)
Max. length	57 km (35 mi)
Max. width	1.2 kilometres (0.75 mi)
Surface area	48.8 km2 (18.8 sq mi)
Average depth	15 metres (49 ft)
Max. depth	15 metres (49 ft)
Water volume	439,600,000 cubic metres (1.552×1010 cu ft)
Surface elevation	556 m (1,824 ft)
References	[1]

The reservoir provides water to the Shand Power Station and to the city of Estevan. A 10-kilometre long pipeline supplies the power station and a 9.2-km long pipeline, which originates along the Souris River river bed at the bottom of the reservoir, brings water to the Estevan water treatment plant. The water pipeline that brings water to Estevan was completed in 2020 after a three year project that changed the source of Estevan's drinking water away from Boundary Dam Reservoir.[3]

Mainprize Regional Park

Mainprize Regional Park (49.3691°N 103.5821°W / 49.3691; -103.5821) is a park in the rural municipality of RM of Cymri No. 36. The regional park is operated by a park authority with offices in Midale. The park includes an 18-hole golf course, Pederson Place (a 5,000-square-foot (460 m²) multi-purpose hall), a beach area on McDonald Lake, water plant, camp groups, and a residential cottage subdivisions. The park is located near the north-west end of the lake, on the eastern shore.[4]

Rafferty Dam

Rafferty Dam is located at the south-eastern corner of the lake, 4.8 km upstream from Estevan. It was built in conjunction with the Grant Devine Dam (formally known as Alameda Dam), which was built further downstream on Moose Mountain Creek, which is a tributary of the Souris River. Both dams are operated by the Saskatchewan Water Security Agency. The dam and reservoir provide flood control along the Souris River, irrigation, and recreation.[5]

The height of the top of the dam is 555 metres above sea level. The maximum height available for flood control is 554 metres. Normal full supply level is 550.5 and the normal drawdown level is 549.5 metres. The maximum draw down is 547.5 metres above sea level. At full supply, the reservoir covers an area of 4881 hectares.[6]

A 10-kilometre long spillway connects the Boundary Dam Reservoir to McDonald Lake, allowing excess water to flow into McDonald Lake. The flow can also be reversed if necessary.

Gallery

• 
  Sunset on McDonald Lake
• 
  McDonald Lake
• 
  McDonald Lake
• 
  Rafferty Dam and reservoir
• 
  The information sign at the look out at Rafferty Dam

See also

• Lake Darling Dam
• 2011 Souris River flood
• Boundary Dam Power Station
• List of dams and reservoirs in Canada
• List of lakes of Saskatchewan
• List of protected areas of Saskatchewan
• Tourism in Saskatchewan

References

External links

• Park Description
• Media related to McDonald Lake (Saskatchewan) at Wikimedia Commons