A $10 million Transportation Department project is designed to stabilize a stretch of the Skagit River that threatens to wash out a section of Highway 20 near Rockport.

Crews are building four engineered logjams with logs, root wads and large concrete blocks in geometric shapes. The blocks are called dolosse, and they look like huge versions of toy jacks.

The Skagit Valley Herald reports ( ) work on the project began Feb. 1. The work will be suspended after April to avoid harming fish. Construction will resume in the fall and is expected to be completed this fall.