The reports showed one of the six areas of Charlottetown Harbour tested with high levels of bacteria. CBC

P.E.I.'s chief health officer has completed a study on water contamination as a result of sewage overflows in Charlottetown Harbour, and found problems after heavy rain.

The Department of Fisheries and Oceans has already raised concerns about water quality, and shut down shellfishing on several occasions this summer and in 2010. The problems come in a section of the sewage system where storm water and the sanitary sewer are combined. Heavy rain overwhelms the sewage treatment system, and raw sewage runs into the harbour.

That raised questions about whether the water was safe for swimming. Eighty seven water samples were taken in six different locations around the harbour in July and August.

• just west of Victoria Park
• near the Seaport building
• near the Energy from Waste plant, past the Hillsborough Bridge
• near Charlottetown Armouries
• near Rosebank-Langley in Stratford
• Kinlock Beach in Stratford

In the first 12 hours after overflows, samples taken near the Charlottetown Armouries had high levels of enterococcus bacteria. Bacteria levels in samples taken at the other five locations were very low and not of concern.

Chief Health Officer Dr. Heather Morrison has had preliminary meeting with the city about ways to warn the public when overflows happen.

"Before next summer we'll work with them to get wording about posting and informing the public that they should restrict recreational water use around that area for a period of time," said Morrison.

"We're particularly talking about full immersion. So people who are swimming in that area."

Morrison used Health Canada recreational water guidelines to decide whether levels of bacteria were safe. Levels at the armouries within 12 hours of the overflow were significantly higher than those guidelines. All other bacteria levels found in the samples were significantly lower.

Water tests taken at Tea Hill Beach in Stratford this summer, that were not part of this study, were also checked, and came back with results within the guidelines.