The Sylvan Lake Groundwater Situation in Perspective and Pictures

The Sylvan Lake watershed and its supply of groundwater are dependent on a fine balance between incoming and outgoing water. The net amount is absorbed and stored underground in the soil, porous and permeable geological glacial deposits, and local aquifers and becomes available for domestic and agricultural use. The following ERCB/AGS maps included in this post show how the natural system and its regional water balance works.

The Sylvan Lake watershed and the lake occupy a small part of that area and are located about 20 km west of Red Deer. See the lake aligned in a NW direction in this series of maps. Zoom in if you are viewing the images on a phone. Check the legends for the colour-coded values.

Central Alberta is relatively dry region and typically receives 500 mm of precipitation annually. The graphic above shows that the foothills to the west receive slightly more rain and snowfall than does the central corridor.

About 60% of the incoming precipitation sublimes or evaporates from snow, ice, wetlands and lake surfaces and by transpiration from crops and forested areas. This maps shows that watershed loses about 300 mm of water by those processes.

The typical annual surface runoff is less than 45 mm.

The average annual minimum groundwater recharge in the Sylvan Lake watershed is about 150 mm.

Local recharge areas are identified by the location of the potentiometric surface (the water level) in water wells compared to the ground surface. Note that most of the watershed area is considered a recharge area with a few notable exceptions in the S and SE. The soggy areas of the Sylvan Lake Golf and Country Club and some farmland to the west are examples of discharge areas.

 

The water table in the watershed is about 950 metres above sea level

Wells in the Sylvan Lake watershed that are completed in the Paskapoo geological formation typically deliver water with high concentrations of Total Dissolved Solids, > 500 milligrams per litre (mg/L).

Hardness, expressed as calcium carbonate equivalent concentrations, is less than 150 mg/L.

All maps are from the 2011 report Edmonton-Calgary Corridor Groundwater Atlas by this team of authors:

Barker, A.A., Riddell, J.T.F., Slattery, S.R., Andriashek, L.D., Moktan, H., Wallace, S., Lyster, S., Jean, G. Huff, G.F., Stewart, S.A. and Lemay, T.G., (2011): Edmonton–Calgary Corridor groundwater atlas; Energy Resources Conservation Board, ERCB/AGS Information Series 140, 90 p.

View this photo album for access to expandable maps.

To supplement the modern maps reproduced above, the hydrogeological work of Gabert and others on the Sylvan Lake watershed is extracted from the AXYS 2005 report Appendix B and available for previewing in an online folder.