Shasta

Snowpack causes concern for possible spring flooding

Snowpack causes concern for possible...

REDDING, Calif. - After winter storms brought heavy rain and snow, parts of the Northstate are under a minor threat for flooding this spring.

That's according to hydrologists like Alan Haynes with the California Nevada River Forecast Center (CNRFC).

Haynes said because of the drought spring flooding is something the region has not seen in a few years. He noted that the issue is not all about snow melt but the additional spring storms that come along with it and increase river levels.

"It hasn't been an issue since really 2011, but that was the last time we had a big snowpack to this magnitude," said Haynes.

The snow pack survey at the beginning of the month showed the state was at 163 percent of normal, Haynes said that is great news but now we have to deal with the effects of all that snow.

"I think the threat is more any sort of warm rain system, with everything have been really saturated you're going to get a good runoff response," said Haynes.

The CNRFC works in conjunction with the National Weather Service and forecasts water levels for the major rivers throughout the state. Haynes said any flooding that occurs in the Northstate this spring should be minor.

"Typically minor flooding would be it's coming out of its banks, it's starting to impact some areas outside of the river. Moderate is: it's starts to impact more than just roads maybe structures. And major is a lot of damage can be expected," said Haynes.

This week's storm is the perfect example of what may happen during the spring. The CNRFC is forecasting the middle fork of the Feather River near Portola to reach flood stage by Saturday.

"But all of the small creeks and streams in the area are going to be running high with this storm, there's a lot of water with the rain coming in and everything being so wet," said Haynes.

The CNRFC also estimates inflows for local reservoirs that way agencies like the Department of Water Resources and the Bureau of Reclamation can adjust according to keep up with the storm.

"We're expecting four inches of rain in the area above Lake Shasta so that's going to generate some pretty good runoff and also [Lake] Oroville should see some good inflows too," said Haynes.

According to their models, the CNRFC expects the southern valley to be hit the hardest along with the Humboldt River and its tributaries in Nevada.

"They're vulnerable because they're channel capacities are so limited especially down south of Sacramento in the southern part of the central valley. All of the reservoirs, when they're releasing water, all accumulates and flows downstream," said Haynes.

The risk for flooding does not last for long. Haynes says the threat will drop off as we get closer to the summer months. "As we get towards the end of May climatologically you're just not likely to see anything real heavy so the risk will go down quite a bit," said Haynes.


Most Popular

Pictures In the News