The destruction it caused was followed by the formation of the county's Flood Control District, which initiated the first flood control projects, such as river canals and reservoirs. The Los Angeles River is on the brink of a new era. In the few years since the flood control canal was reclassified as a “navigable waterway,” the region has once again embraced its strange amalgam of concrete and nature, which winds approximately 51 miles from the San Fernando Valley to the ocean in Long Beach. There have been eight major floods in the Valley since 1861, but the Los Angeles River flood in 1938 was one of the worst.
The rains lasted 3 days and the Great Tujunga Wash dam broke. Seventy-seven of its expansion basins were destroyed. The phones and electricity were turned off. Lot and the Olive Avenue bridge were razed to the ground.
It took 30 days to clear the debris from the storm. Although the 1938 flood caused the greatest damage of all floods in Los Angeles history, rainfall and river peaks were not even close to the Great Flood of 1862, the largest known flood by total volume of water. The flood was caused by a pair of ocean storms that spread inland across the Los Angeles Basin in February and March 1938, causing abnormal rainfall across much of the coast of Southern California. In 1952, Leigh Wiener, photographer for the Times, was reportedly sent to the scene of a car accident on South Alvarado Street, Los Angeles.
The floods that occurred between 1914 and 1934 were some of the most economically devastating floods the Los Angeles area has historically experienced. At the end of March 1, a new, more powerful storm arrived, dropping 10 inches of rain in Los Angeles and more in the mountainous areas. Around 108,000 acres (44,000 ha) were flooded in Los Angeles County, and the most affected area was the San Fernando Valley, where many communities had been built during the economic boom of the 1920s in low-lying areas that were once used for agriculture. Five people died when the 250-foot Lankershim Boulevard bridge collapsed on the Los Angeles River in Universal City.
Frank Gehry is working to revitalize a three-mile stretch of the Los Angeles River concrete canal and turn it into a picturesque park. In Los Angeles alone, more than 1,500 homes were left uninhabitable and aid agencies sheltered 3,700 residents. Originally an alluvial river that ran freely across an alluvial plain, the 51-mile path of the Los Angeles River was unstable and unpredictable, as the river's mouth frequently moved from place to place. For centuries, the Los Angeles River has been prone to flooding during periods of heavy rain, but it could transform into just a trickle and even into swamps for the rest of the year.
But it pales in comparison to a 50-year flood that hit Los Angeles and the Santa Clarita Valley in February-March 1938.Although some work was already under way on the river canal at the time, the 1938 flood was the main impetus to channel the Los Angeles River in particular, accelerating the flow of flood water to the sea. The overflow flooded a strip of low-lying cities and farmland between downtown Los Angeles and the port of Long Beach.