Sewage lagoon discharge can lead to algae in Lesser Slave Lake

To the Editor:

In the 90s while attending Okanagan university applied science degree, water and wastewater treatment were a major part of my final thesis. I ended up doing wastewater tests for two summers in the Vanderhoof-Smithers area. Fecal coliform and E.coli were always present. There was disinfection for lagoon discharge. Chlorine was used in a very limited way.

As a born and bred native of the Lesser Slave Lake area I’ve paid particular attention to the effects of lagoon wastewater on lakes like Lesser Slave Lake.

There are 10 lagoons discharging under-treated sewage into the west end of the lake.

While the M.D. of Lesser Slave River operates a modern wastewater plant at Canyon Creek, the west end consists of 10 primary treatment lagoons discharging annually into Lesser Slave Lake.

Environment Canada has confirmed eutrophication caused by lagoon discharge exists in many lakes. Nutrients, mostly nitrogen and phosphorous, exist in high amounts in all lagoons. The effluent is like a liquid fertilizer.

Warm lake water, sunlight and nutrients create perfect algae growing conditions. (An) M.D. of Lesser Slave River councillor has correctly voiced concern about excessive algae blooms.

Ten Alberta lakes were declared toxic (with) blue green outbreaks and issued warnings for dogs, cats and people to stay away.

Lesser Slave Lake is a moving lake flowing west to east. Heavy rainfalls have flushed the lake several times. A low rainfall period will allow algae to flourish. A toxic blue green outbreak is still possible this year.

20,000 people, including five First Nations get their water from the lake. A toxic blue green algae outbreak will result in boil-water advisories.

A project has been proposed that will remove nutrients from lagoon wastewater and will greatly enhance the disinfection of effluent prior to discharge. Environment Canada has already endorsed the project. Alberta Environment will grant an approval prior to discharge.

David Lainchbury
High Prairie Alberta