In the late 1910s, Sacramento County improved the road between Isleton and Paintersville and provided free ferry service across the river at these two towns. The ferries were replaced with bascule bridges in the early 1920s. The two bridges are almost identical, except the Isleton Bridge has tied arch approaches and the Paintersville Bridge has through truss approaches. They both have the Joseph Strauss patented heel trunnion double leaf spans for a 200 ft channel opening. They are both on concrete piers with timber piles protecting the piers at the channel opening. The two bridges are about 20 miles apart. Thirty years later the bridge at Walnut Grove was built between the older bridges.