OSO, Wash. -

State workers with the Department of Natural Resources are trying to increase the flow of the Stillaguamish River through the Oso mudslide to reduce the flooding in the debris and clear Highway 530.

Water backed up by the March 22 slide flooded part of the highway upstream. The state Transportation Department is trying to reduce that flooding as workers clear debris from the highway, the shortest route between Interstate 5 and Darrington.

Geologists and hydrologists with the state, Corps of Engineers, National Weather Service and U. S. Geological Survey also are working with Snohomish County to drain backed-up water at the landslide.