Flooding is common the Red River, which drains into Lake Winnipeg.

Record snowfalls in North Dakota have left Manitoba water experts nervous about the potential for significant flooding in the Red River Valley in the spring of 2009.

The United States National Weather Service predicts a 66 per cent chance of major flooding and a more than 90 per cent chance of minor to moderate flooding in the Fargo area to the end of April 2009.

Fargo and Grand Forks, N.D., like Winnipeg to the north, sit on the banks of the Red River, which last brought catastrophic floods to the region in 1997. In the winter of 1996, precipitating that flood, the Fargo-Grand Forks area had received 51.8 centimetres of snow by this time of year. So far in 2008 the area has received more than 75 centimetres of snowfall, eclipsing a 1929 record — and it is still snowing.

The snow, atop ground made very wet by autumn rains, has left Alf Warkentin, Manitoba's senior flood forecaster, worried.

"The probability of flooding in Manitoba is significantly higher than normal," Warkentin told CBC News. "However, it will still depend a whole lot on what happens in the next four months."

He is watching to see how much more snow falls in the next few months, and whether the spring thaw is gradual or sudden.

What's happening in North Dakota "is not good news" Warkentin said. "We're always interested to hear what's happening on the U.S. side because it's the largest part of the [Red River] basin."

Things aren't shaping up for a particularly dry spring, he noted.

"There is some concern," he said. "But quite often flooding in the Fargo area doesn't translate into flooding in Manitoba. We just have to hope the weather is favourable in the next four months."

Warkentin said Winnipeg, with a population of over 700,000, should be able to handle whatever the Red River throws at it next spring, thanks largely to the $665-million expansion of the Red River Floodway — the ditch that diverts Red River floodwaters around the Manitoba capital.

And farms and towns in the valley between Winnipeg and the U.S. border have increased flood protection measures since 1997.