REGINA -- The Saskatchewan Water Security Agency says cities affected by an oil spill on the North Saskatchewan River could reopen their water intakes before winter.

Agency spokesman Sam Ferris says there's no definitive timeline, but adds he's "fairly confident" most water intakes can be used again before freeze up.

The cities of North Battleford, Prince Albert and Melfort had to shut off their water plant intakes after the July spill by Husky Energy(TSX:HSE) and find alternate sources.

Ferris says of the 135 water samples taken from the river by the agency, only one did not meet drinking water guidelines and 17 were too high for guidelines for aquatic life.

He says 12 sediment samples taken from the river bottom were also too high, but that's not unexpected because oil doesn't like water and goes into the sediment.

The Saskatchewan Ministry of the Environment said last week that almost 75 per cent of the estimated 225,000 litres of petroleum that spilled has been recovered.

Meanwhile, the City of Prince Albert says the results of its latest tests on water samples from the North Saskatchewan River found hydrocarbons at levels below Canadian drinking water guidelines.

The city also said that samples from the storm water retention pond, the South Saskatchewan and the Little Red rivers "did not have hydrocarbon contamination for any regulated compounds.

"The laboratory detection levels are significantly lower than Canadian drinking water quality guidelines."

The samples were taken on Aug. 26, the city said in a news release Thursday.