Crews are monitoring the Nechako River in Prince George, B.C. after a rapid rise in temperature led to localized flooding of some homes.

The flooding was first reported to officials Sunday night in the North Nechako neighbourhood on the northwest edge of the city.

Fire chief John Iverson said there was a "sudden and unexpected" movement of ice that led to the Nechako River flowing onto people's properties and into some basements, an event that he said was "unusual." 

"The river's been fairly stable over the last couple of weeks, and for this to change in this fashion is very unusual," he said.

localized flooding

So far flood damage has been localized to a single neighbourhood, but crews are monitoring for changes elsewhere along the Nechako River. (Andrew Kurjata/CBC)

There has been a rapid change in temperature in Prince George, with temperatures dropping to below -30 C on Dec. 28 and then rising above freezing by Jan. 5. 

Temperatures in the northern city are expected to drop below freezing starting Tuesday.

According to Environment Canada, these thaw cycles are a major cause of flooding as ice jams cause water levels to rise during river melts.

In the winter of 2007-08, ice jams led to localized states of emergency and evacuations in Prince George, as well as widespread damage to properties and parks along the river. In Feb. 2017, record high temperatures led to flooding throughout the city. 

Iverson said he wasn't able to predict if the flooding would spread, and his focus was on helping affected homeowners and monitoring for potential changes elsewhere along the Nechako.

The fire department is also advising people to stay off the river and use caution along its shores as the melting continues.

Water levels expected to return to normal: River Forecast Centre

B.C. River Forecast Centre hydrologist Charles Luo said his team measured a 1.3-metre rise along the Nechako River over the weekend due the warming temperatures.

Jeremy Butterfield said he didn't realize his property was flooding until officials knocked on his door late Sunday night.

The Nechako had quickly covered most of his backyard and water was seeping into his basement.

water flooding Nechako

Rising water from the Nechako River covered yards and seeped into four Prince George homes Sunday night. By Monday evening, the river was declining. (Andrew Kurjata/CBC)

Along with city crews, he stayed up most of the night setting up pumps and hoses to redirect water back to the river. 

Butterfield said he was lucky to be in the midst of renovating his basement, so damage was limited.

He also said it was the first time in his twenty years of living along the Nechako he's seen the river moving in January.

"I've never seen this river flowing in January. I can't remember a winter like this," he said.

Water levels were falling by Monday night, and Luo said with Environment Canada forecasting a return to freezing temperatures for the rest of the week, he doesn't expect further flooding.