The southbound lanes of Highway 395 over the blue bridge closed at 9 p.m. Friday and won't reopen until 5:30 a.m. Wednesday.
A contractor for the state Department of Transportation will be working to replace 28-year-old expansion joints on the bridge.
Similar work was done last weekend on the northbound side. The southbound closure was extended a day because of additional work crews had to do on the northbound side.
The southbound lanes of Highway 395 will be closed at Court Street in Pasco.