The Muskrat Watershed encompasses an area that stretches over five municipalities in the County of Renfrew:
• North Algona Wilberforce
• Township of Laurentian Valley
• Township of Admaston/Bromley
• Township of Whitewater Region
• City of Pembroke
The Watershed includes Muskrat Lake, the Muskrat and Snake Rivers, Lake Dore, Black Creek, Mink Lake, Mink Creek, Olmstead Lake, and numerous small creeks, streams, lakes and wetlands.
The total Watershed covers an area of over 500 square kilometres with the Muskrat River emptying into the Ottawa River in the City of Pembroke.
Muskrat Lake is the largest body of water in the Watershed and is a natural resource valued for its fish and wildlife habitat, recreational activities, and residential development opportunities. The lake supports many species of fish - pike, pickerel, bass, lake trout, rainbow smelt and perch, among others. The lake also hosts a wide variety of waterfowl, aquatic and other animal species, and provides drinking water for some shoreline property owners and the village of Cobden.
Over the past several decades Muskrat Lake, and to some extent other areas of the Watershed, have seen a serious and significant decline in water quality, most specifically related to nutrient loading.
Nutrient loading involves an increase in the mass of nutrients (particularly nitrates and phosphates) entering a water body. Over a prolonged period, nutrient loading will have a significant impact on water quality and aquatic ecosystem health. This process is called eutrophication.
Water quality monitoring on Muskrat Lake
indicates the following problems:
• Phosphorus concentrations are very high, almost double
Ontario’s Provincial Water Quality Objective for inland lakes
• There are no areas or zones in the lake where
dissolved oxygen concentrations are low.
• There is a high risk of blue-green algae blooms with
related toxins, present three of the past six summers.
• The Snake River Watershed and internal loading are
main nutrient sources.
Algal blooms within Muskrat Lake have been increased in frequency and severity in recent years. The presence of blue-green algae (potentially toxic) has been confirmed in the lake in three of the past six years (2007-2013).
Declining water quality on Muskrat Lake has resulted in negative impacts on shoreline property owners, recreational users, residential development, the tourism industry, fish species and aquatic habitat, and has generated public health concerns related to the blue-green algae.
We believe that improvements to water quality can occur, but will require the development and implementation of a comprehensive phosphorus reduction strategy for the Watershed.