Nepahwin Lake Watershed is located in the McKim township and part of the larger Ramsey Watershed Unit. Nepahwin Lake’s watershed encompasses 744 hectares including two upstream lakes (Still and Bennett Lake), commercial and industrial areas, the Idylwylde Golf and Country Club, trails and a parking lot at Laurentian University. It is fairly densely populated with, condominiums , apartment buildings and several residential areas; amongst them more than 230 lakefront homes.
Nepahwin was formed by the glaciers as they scoured the landscape more than 10,000 years ago. The lake itself is 127.0 hectares in size and has a shoreline perimeter of 11.8 kilometres. Nepahwin is one of the deepest lakes within the City of Greater Sudbury with a maximum depth of 22 metres and a mean depth of 8.3 meters. The flushing time of the watershed (i.e. the number of years
it would take to empty and fill the basin of the lake) is 3.616 years.
With the completion in 1956 of Highway 69’s southern entry to Sudbury to connect to the Trans-Canada Highway, residential building in the 1950’s and continuing into the 1960’s and 70’s boomed. This was followed in the 1980’s and 1990’s by mall and plaza development and further lakeshore condominiums. Nepahwin Lake Watershed: Its Past, Present, and Future. (A. Hallman, 1996) provides a detailed and delightful history.
Some developed lots have retained a vegetated shore with a good buffer zone, but others have manicured green lawns right to the shore or have constructed retaining wall structures. In all, Nepahwin falls into the range of having 21-25% of its shoreline disturbed or negatively altered.
Nepahwin Park Beach (supervised) is just off Paris Street and offers a beach and small park area.
Laurentian University Beach (supervised) is off the Laurentian Trail, which joins Loach’s Road and the Laurentian University Campus. The trail does not allow for motorized vehicle passage, so walking or biking down the trail are the options for accessing this beach. Stewart Park Beach (unsupervised) is off Stewart Drive, and offers some playground equipment, but the beachfront area is quite small.
City of Greater Sudbury: Local Lake Descriptions: Lake Nepahwin https://www.greatersudbury.ca/play/beaches-and-lakes/lakes/local-lake-descriptions/lake-nepahwin/