Water levels are expected to start dropping on the lower Fraser River on Monday, reducing the threat of flooding for several hundred people in communities in B.C.'s Fraser Valley and Lower Mainland.

It's part of a larger trend, as the threat of flooding eases across B.C., say emergency officials.

Only the Bulkley, Telkwa, Liard and Columbia rivers remain under flood warnings. But the water flows moderated in all four rivers during the weekend.

Flood warnings were downgraded on three other rivers, including the Skeena and upper Fraser.

But officials warn rivers could rise again if several days of hot weather causes rapid melting of still heavy snowpacks.

More than 200 people have been forced from their homes in the past week in the Smithers, Prince George and Terrace areas, as well as the Mount Currie reserve north of Whistler.

Natural gas line damaged

Residents of Prince Rupert are being asked to conserve natural gas, after their main pipeline was knocked out by flooding and debris from the Skeena River.

The north coast city is now getting by on residual gas that's still in the main line, equivalent to a three-day supply.

Mayor Herb Pond said industry, schools and the hospital are all running on backup systems to preserve the precious little natural gas that's left.

"We have survived far worse than this in the dead of winter. I know the people of Prince Rupert will pitch in and we'll make it through."

Pacific Northern Gas spokesman Tom Leach said the company's repair crews are having a tough time getting at the damaged line.

"It's a fairly remote area. It's tough to get at. There is no road access again because of the higher river levels. If the weather conditions hold we should have the repair completed in a couple of days."

In the meantime, Prince Rupert is depending on a special shipment of fuels being brought in by barge from Vancouver.