Northern News Services
During spring run-off, bacteria levels in this storm water outlet near School Draw Avenue were hundreds of times higher the recommended limit. A recent health risk assessment indicates the seasonal spike in bacteria levels poses no health risk. - Richard Gleeson/NNSL photo
The five-page health risk assessment was done as a follow-up to a study done last spring that showed high levels of E. Coli and other bacteria in city storm sewer outflows.
The follow-up was done by the Stanton Regional Health Board using samples taken this summer in and near sewer outflows into Back Bay and Yellowknife Bay.
"It is recommended that residents of Yellowknife should not play or swim in the storm drains or at their immediate outflow into Great Slave Lake," wrote the health board in its report.
The board concluded the high fecal coliform counts detected in the initial study, done by the Department of Indian Affairs and Northern Development, were likely caused by animal feces flushed through the sewers during spring run-off and heavy rains.
In conducting its study, the heath board took samples from the storm sewer drains and from the bay waters around them Aug. 8 and 10.
Bacteria levels in only one storm drain sample exceeded Canadian guidelines. Levels in the samples from Back Bay and Yellowknife Bay were well below the guidelines set for recreational use.
The city is still awaiting word from the Mackenzie Valley Land and Water Board on its water licence application.
The six-year licence the city is operating under expires Dec. 31. A 60-day extension of the term has been granted by the board.
The DIAND study was done as part of the review of the licence application. In response to the initial study, the Department of Resources, Wildlife and Economic Development recommended the city implement storm water sampling programs and investigate alternatives for treating storm water.
The land and water board will likely be making a decision on the city's licence application early in the new year.
Water used July-September: 711,778 cubic metres
Sewage effluent discharge: 788,704 cubic metres
Volume of Ruth Inch pool: 663 cubic metres
Source: City of Yellowknife quarterly water licence reports