Sweetwater Dam Helped Keep the San Diego River in Its New Place

Media
33 minutes ago
1 min read

In 1853 the U.S. Army sent a lieutenant to San Diego to move a river. He moved it, and it did not stay moved.

The San Diego River used to empty into San Diego Bay, and every flood season dumped another load of sand and silt into the harbor. A silting harbor meant no deep-water port, and no deep-water port meant no city worth building. So the Corps of Topographical Engineers assigned Lieutenant George Horatio Derby to throw a levee across the river's course near Old Town and push the water west into False Bay, which we now call Mission Bay.

The dike was finished in 1853. A flood that same year tore into it and sent the river back toward the harbor. Repairs eventually redirected the water again by 1875, and another major flood in 1884 damaged the works once more.

It took the better part of a century to finish what Derby started. Sweetwater Dam went up in 1888, six more dams followed on the San Diego River, and the channel was not truly controlled until the 1950s.

The dike itself is gone. What remains is California Historical Landmark No. 244, listed in 1936, marked near Taylor Street and Presidio Drive.

Mission Bay is a manufactured playground. The river feeding its mouth was aimed there on purpose.