Cleanup of an oil spill along the North Saskatchewan River will be put on hold as water levels are expected to rise by up to two metres in the coming days, a provincial government spokesman said Thursday.

Increased flows caused by unusually heavy rainfall west of Edmonton are making their way east. Peak levels at the Alberta-Saskatchewan boundary are expected late Friday or early Saturday.

"Some cleanup activities will be temporarily discontinued. Some of the shoreline infrastructure — things like some docks, launches and vehicle pads and booms — are going to have to be removed from the area so that they don't get damaged with the high water," said Wes Kotyk with Saskatchewan's Environment Ministry.

"As soon as things start to stabilize and recede, the plan is to get right back to things as quickly as possible."

Kotyk said provincial authorities and Husky Energy (TSX:HSE), the company responsible for the spill, still expect to be able to finish shore cleanup before water starts to freeze in October.

Almost 75 per cent of the estimated 225,000 litres of petroleum that spilled has been recovered, he said.

The government says there have been 144 confirmed wildlife deaths, including 51 aquatic species, since Husky's pipeline leaked last month near Maidstone, Sask.

The line was carrying heavy oil mixed with a lighter petroleum product that enables the crude to flow.

Also Thursday, the Saskatchewan Water Security Agency said one sample out of 120 taken from the river did not meet drinking water guidelines and hydrocarbons were found in the sediment at the bottom of the river at five monitoring sites.

The agency's Sam Ferris said the results are "generally encouraging."

"The more data that I have that shows what's going on, the happier I'm going to be. It just gives you more assurances of what's being encountered. If you know levels, then it's relatively easy to start to understand if those substances can be removed."

The cities of North Battleford, Prince Albert and Melfort have had to shut off their water plant intakes and find alternatives because of the spill. For now, all three are well supplied, said Ferris.

A leak was found on one of the hoses bringing in water to Prince Albert, but so far it has not changed the situation for that city, he added.

Ferris said authorities are still waiting for more information about health risks and possible filtering options before treatment plants can start drawing from the river again.

"I'm hopeful that use of the intakes will be able to resume some time in the next few weeks. The only thing that's going to potentially influence that is it'll be really interesting to see what happens, because of the increasing river flows that we're going to experience over the next week or so."