High bacteria counts kept swimmers off Black Rock Beach in Point Pleasant Park for 17 months. (CBC)

Two beaches in Halifax have re-opened after a sewage flood last week.

The Dingle and Black Rock beaches, which had only just reopened after being closed for more than a year, were shut again when heavy rain overwhelmed the city's system.

On Wednesday, the city said those beaches are once again safe for swimming.

Earlier this month, many residents told CBC they are still reluctant to swim in the harbour after decades of raw sewage being pumped directly into the water and the failure of the Halifax sewage treatment plant in 2009.

Halifax Regional Municipality officials said in early July they are confident that the water meets swimming safety standards now that the Dartmouth, Herring Cove and Halifax sewage treatment plants are up and running.

In January 2009, the $55-million Halifax treatment plant was disabled by a power failure that caused catastrophic flooding just weeks after the city took ownership. It resulted in raw sewage once again flowing directly into the harbour.

The plant was finally operational again in June 2010.

The three Harbour Solutions Project plants are designed to treat four times the average dry weather flow. This means following a heavy rainstorm, flows entering the treatment facilities may temporarily exceed the design capacity.

Following heavy rain, city officials warn that swimmers stay out of the harbour for three days.