The San Joaquin River has been used a lot for shipping of products via boats and ships, otherwise known as navigation. The river was first used for navigation during the California Gold Rush of 1849. Boats carried people over up the river to look for gold in the mountains. Now, there is a channel that runs all the way upriver to the city of Stockton. This channel allows big ships to sail in the river up to this point. Sediment, however, has clogged a lot of the river channel above this point, preventing big ships from going any farther.