Icy roads and at least one crash along U.S. 26 near the Oregon Zoo exit in Portland has caused eastbound traffic to slow to a near standstill Tuesday.

An Oregon Department of Transportation incident response worker was hit by a car while answering a call on the roadway around 7:30 p.m., according to Don Hamilton, an agency spokesman. The worker wasn't seriously injured, he said.

A TriMet bus was involved in another crash on the eastbound side of the roadway, Portland police said. No one was seriously injured in that crash either.

The road conditions have impacted traffic on both sides of the roadway.

Other collisions have been reported in other areas due to snowfalls throughout the Portland metro area Tuesday.

Authorities in Washington County advise motorists to have traction devices on their vehicles when traveling along portions of Southwest 175th Avenue, Barnes Road and Cornell Road because of icy roads.

The Portland Bureau of Transportation said chains are required on tires of vehicles on West Burnside Street and Southwest Sam Jackson Park Road. Gresham police said chains are required when driving on Interstate 84 from Troutdale to Hood River.

-- Everton Bailey Jr.