The District of Chetwynd in northeastern British Columbia has declared a state of emergency after heavy rain caused havoc and flooding throughout the region on Wednesday.

The region is cut off from the rest of the province after the only highway was closed by flooding Wednesday afternoon.

The district says 79 millimetres of rain fell by noon and a further 30 to 50 millimetres is expected in the next 24 hours.

"We all need to take measures to ensure our families, structures and livestock are safe at this time," said Chetwynd Mayor Merlin Nichols in a written statement.

Highway 97 is closed in both directions through the Pine Pass, about 150 kilometres north of Prince George.

Motorists are being turned back at the Mackenzie Junction to the south and Chetwynd to the north.

Motorists stranded

"We got turned around. Pine Pass is flooded out and it's all closed up," said Ray Geroux, who got stranded in Chetwynd while trying to get home to Vancouver.

He's not sure when the route will reopen.

"They said anywhere from two days to two weeks depending on when the rain stops and how bad the flooding is," said Geroux.

Geroux plans to backtrack and spend the night in Dawson Creek before contemplating the seven-hour detour through Grande Prairie, Alta.

He said the flooding in Chetwynd is pretty bad, with parking lots and rail lines awash.

Flood watch for all of northeast B.C.

A flood watch is now in place for a huge swath of northeastern B.C., from Pine Pass through to Fort Nelson.

The B.C. River Forecast Centre said that river levels continue to rise and will approach or exceed their banks in other areas by Saturday.

Although flooding is possible throughout the region, there are particular concerns about the Moberley, Kiskatinaw and Fontas rivers, which are all expected to reach 10- to 20-year record highs and to peak on Friday or Saturday.

According to the B.C. River Forecast Centre, water levels in smaller streams at higher elevations rose rapidly Wednesday near Pine Pass, Chetwynd, Tumbler Ridge, Dawson Creek, Fort St. John and Fort Nelson.

They're forecast to continue rising with flooding in low-lying areas.

Meanwhile, snow fell Wednesday in Tumbler Ridge, creating slushy and slippery sections on local highways.

On Wednesday afternoon, about 2,000 homes and businesses in the Peace region were without power.

Fort St. John also shut down all city trails as high winds knocked over trees.

Officials with Caribou Road Services and with the Peace River Regional District weren't available for comment, saying they were too busy.