Final work was completed last week to prevent potential landslides near the Green River Bridge in the Black Diamond area, according to the state Department of Transportation.

The installation of drainage pipes to pull water away from the site capped efforts to stabilize the hillside, said a spokesman for the department (DOT).

Motorists use the road between Black Diamond and Enumclaw for about 9,000 trips per day, DOT officials said.

Since July, DOT workers have placed long soil nails and concrete to strengthen the slope near the southeast end of the span, which is also known as Kummer Bridge.