Beach closures in the Ottawa River Watershed

The City of Ottawa has four swimming beaches that are monitored for bacteria on a daily basis during the swimming season (mid June to end of August). In 2006, the beach at Petrie Island was closed to swimming for 45 days (>60% of the swimming season) due to high bacterial counts in the water samples.

Given that the beach is downstream of 2 major wastewater treatment plants and numerous combined sewer outlets, this data was not too surprising to some, but very concerning for the public who want to swim in the river without risking illness.

Given the poor water quality in 2006, the City of Ottawa funded the National Water Research Institute (Environment Canada) to study the water quality data from the vicinity and investigate the source(s) of fecal pollution responsible for the poor water quality. This investigation utilized microbial source tracking to determine the likely source of the E.Coli (birds, human, dogs, cows, etc.).

The full report is available on the City of Ottawa’s website: An Investigation of the Sources of Fecal Contamination at Petrie Island Beach on the Ottawa River in 2007.

In 2007 the water quality at the site improved and there were only 6 no-swimming advisory days at Petrie Island. There was very little rainfall during the summer of 2007 which likely accounted for some of the improved results.

Our Riverkeeper has carefully read the Petrie Island Report and offers the public her comments on the situation. To read the full critique of the Report, click here

Important findings from the report

• Human fecal pollution was evident by observations of floatables found on the beach during the data collection stage.
• Fecal pollution at the beach is attributed to humans and birds.
• The sand acts as a reservoir for E. Coli and concentrations in the sand tend to increase throughout the summer.
• Both E.Coli concentrations and the occurrence of the human Bacteroides DNA marker were more numerous at the beach after rain events.
• Bilberry Creek, a small tributary that enters into the Ottawa River upstream of Petrie Island, has high E. Coli concentrations that originate from humans. During rain events, detection of human fecal matter is higher in the creek.
• E. Coli and human Bacteroides concentrations were lowest at the Ottawa River transect above the City of Ottawa and City of Gatineau municipal wastewater treatment outfalls.

Interesting Notables

• The E. Coli and Bacteroides concentrations were, for the most part, more numerous on the Quebec side of the river than on the Ontario side.
• However, cluster analysis suggests that the human fecal pollution is more closely related to fecal sources on the Ontario side. This is likely because Ottawa is a bigger city and releases higher volumes of wastewater effluent and stormwater than the City of Gatineau. Flow dynamics or the river likely have an impact as well.
• E. Coli from Ottawa’s WWTP are dead (from chlorine) as opposed to that from Gatineau.
• The E. Coli concentrations were highest in the sand pore water, yet the human Bacteroides DNA marker was less commonly found in the sand pore water.

Concerns and Recommendations

• Investigate Bilberry Creek ASAP – likely there are houses directly connected to the storm sewer instead of sanitary sewer or there are illicit discharges to the storm sewer. Don’t wait to do more water quality monitoring at the creek outlet; get out there and investigate where the fecal contamination is originating.
• We should focus on all City beaches and water quality in general, not just on Petrie Island. Westboro Beach has the highest numbers of beach closures. Britannia and Mooney’s Bay are swimmable only because of band-aid solutions to reduce E. Coli concentrations at the sites.
• The Riverkeeper has concerns that the City of Ottawa is acting too slowly on these water quality issues. Currently, they are sitting on the Baird Report (a report prepared by consultants) and have not released it to the public despite an eager audience for it. For the Petrie Island problem, the City is taking a year to come up with recommendations for actions. This seems like a stall tactic – we already know what the problems are, let’s get to fixing them!
• The Riverkeeper recommends the City implement a no swimming rainfall rule immediately for Petrie Island instead of taking a year to come up with a formula to use.
• When working on a model to predict relationship between rainfall and bacterial levels for Petrie, the City should also take other factors into consideration (e.g., water levels, river currents, waves).
• Solutions must come from Ottawa and Gatineau and both cities should be working together and sharing data.
• Map areas adjacent to the river and its tributaries that are on septic (both sides of the river)
• Use Best Management Practices to target primary sources of bacteria – there are progressive solutions that incorporate natural vegetation at stormwater outlets as well as practices to reduce the amount of E. Coli in beach sands. Let’s learn from progressive cities that have success stories.
• Stormwater is a big problem and we must treat it! Note the Province of Ontario’s Procedure F-5-5: It requires municipalities with combined sewer systems to prevent sewage from entering our waterways, to protect water quality and ensure all beaches remain open 95% of the swimming season.
• We need improved communication with the public – people are part of the solution and they need to be better informed.

In Summary, this report is an excellent first step that uses science to help determine the sources of contamination found at Petrie Island Beach. The Riverkeeper urges the City of Ottawa to work quickly to implement actions that will allow all of us to swim safely in the Ottawa River.