Near site of Oso mudslide, concerns over heavy rain, new path of river

OSO, Wash. -- Flooding is a big concern in Snohomish County, especially near the Oso mudslide.

The concern is that the path of the Stillaguamish River has changed as a result of the mudslide, and the effect of that on people living nearby is unknown.

Wednesday’s storms are just the beginning of the rainy season. County officials and the U.S. Geological Survey said they are keeping a close watch on the water levels.

Kayla Baum and her daughter live right along the Stillaguamish, about a mile from the slide zone.

Baum said flooding has been an issue for her family in the past.

“We’ve seen the water come up to where our trailer is,” she said. “I worry about my grandma.”

Snohomish County and the USGS have placed additional river gauges on the North Fork Stillaguamish to catch early signs of rising waters.

The National Weather Service is paying close attention, too.

“We haven’t had a heavy wet season since the Oso slide (which took place March 22) and so as we put more water in the river, it’s going to start changing things a little bit,” said Kirby Cook, of the National Weather Service.

The new gauges are being used to help the NWS build better flooding forecasts this season.

“We’re using it to monitor what’s going on through the slide and to see if there’s any pooling again behind the slide area,” said Cook.

The slide area has stabilized since spring – but all the new sediment could cause subtle changes to the river’s flow.

“It can cause it to maybe ... rise in different parts of the river, spread out differently,” added Cook.

“This is a lot of rain just for one day,” Baum said Wednesday.

It’s that uncertainty that has neighbors like Baum worried about the next few months.

“I don’t think anybody really knows what’s going to happen,” she said.