After record floods, keep watch for signs of landslides

EVERETT — As Snohomish County rivers receded after days of heavy rain and record flooding of the Stillaguamish River, officials fear another disaster: landslides.

“It’s prime landslide season, we’re paying attention as soon as it gets wet,” said Scott North, spokesperson for the Snohomish County Department of Emergency Management. “People should pay attention to the signs.”

According to a guide compiled by the Washington Geological Survey, hints include:

● Cracks in soil;

● Tilted or bent trees;

● Increased spring activity or newly wet ground;

● Hummocky or uneven terrain;

● Sagging or taut utility lines;

● Sunken or broken road beds;

● Movement of soil away from foundations;

● Leaking or broken water pipes.

People can also check if an area is prone to landslides through the Snohomish County Hazard Viewer online.

As waters were still receding Friday, damage estimates were unavailable. County officials asked the public to fill out a flood impact survey. Officials also evaluate damage through video footage, boots-on-the-ground observations and talking to city and town officials.

All that information will make the case for recovery resources and grant funding.

Trestle traffic

On Thursday, massive logs and other woody debris jammed the Snohomish River, requiring crews to slow traffic on the U.S. 2 trestle east of Everett.

The river reached “moderate” flood stage this week in Snohomish.

A loader on the trestle split up large hunks of timber while crew in boats pushed them downstream. The emergency maintenance between 50th Avenue SE and Highway 204 prevented logjams, according to the state Department of Transportation. It’s often necessary when the Snohomish River rises under the trestle.

The transportation department closed eastbound lanes on U.S. 2 from Thursday at 10 p.m. until 1:30 a.m. Friday, to make room for heavy machinery.

“If the logjams aren’t dealt with, pressure can build against the piers and potentially damage them,” the department wrote on Reddit. “The debris can also cause water to swirl and move in irregular patterns, potentially eroding the dikes on either side of the slough, increasing the risk for even more flooding.”

Elizabeth Mount, a spokesperson for the department, said that thanks to early storm forecasts, the equipment was ready ahead of time and the crew gradually removed the debris from the water.

Going east on U.S. 2

At Stevens Pass, the ski season’s start date remained unclear Friday.

After last week’s snow, staff felt hopeful — but then it warmed up and rained, delaying the opening. Seeing new flurries this week, Vail Resorts spokesperson Amanda Bird was optimistic.

“Thankfully, it is snowing again! We’re on a wait-and-see approach and we’re hoping this system delivers,” she said in an email.

A winter weather advisory for elevations over 3,000 feet expired at 1 p.m. Friday.

The National Weather Service predicted more rain going into the weekend in the lowlands, with heavy snow and freezing rain at Stevens and Snoqualmie passes — and no major flooding in the near future in Snohomish County.

Aina de Lapparent Alvarez: 425-339-3449; aina.delapparentalvarez@heraldnet.com; Twitter: @Ainadla.

Maya Tizon: 425-339-3434; maya.tizon@heraldnet.com; Twitter: @mayatizon.