Claim: Bouldin Island, an island located in Northern California, is bounded to the north by the South Mokelumne River which connects the island to the adjacent sea.
Evidence: Bouldin Island is an island in the Sacramento-San Joaquin River Delta in San Joaquin County, California, 20 kilometers (12 mi) northwest of Stockton on the Stockton Deepwater Shipping Channel. The 2,400 ha (5,900-acre) island is bounded to the north by South Mokelumne River which separates the island from Staten Island. A swing bridge over the Mokelumne River on SR 12 connects the northwestern part of the island to Andrus Island. Sacramento-San Joaquin River Delta The river flows west from a rugged portion of the central Sierra Nevada into the Central Valley and ultimately the Sacramento–San Joaquin River Delta, where it empties into the San Joaquin River-Stockton Deepwater Shipping Channel. The Stockton Deepwater Shipping Channel is part of the vast Sacramento–San Joaquin River Delta that has a connection to the Pacific Ocean.