Early 1900s

In the early 20th century, several catastrophic floods devastate Southern California, causing a significant loss of life and millions of dollars in property damage. In response, the Army Corps of Engineers channelizes the Los Angeles River, Ballona Creek and their tributaries with concrete in the 1930s and 40s, initiating an underground urban drainage system. Channelization is complete in 1960 and results in a 1,500-mile storm drain system comprised of more than 30,000 catch basins and 100 miles of open channels.

As Los Angeles’ population rapidly grows in the mid-1900s, rainwater that was once absorbed by miles of undeveloped land begins to runoff the newly paved and developed areas, leading to an increased amount of water flowing into Los Angeles’ local creeks and rivers. The increased urban runoff inadvertently picks up trash and toxins left on streets and gutters, creating a toxic soup that flows through local waterways and straight to the ocean every time it rains in Los Angeles.  


The national Environmental Protection Act is enacted on January 1.


Amendments to the federal Clean Water Act result in a National Pollutant Discharge Elimination System (or NPDES) Municipal Stormwater Permit for storm water similar to that for waste water treatment plants.


The California Regional Water Quality Control Board issues the first NPDES municipal storm water permit to the County of Los Angeles and 84 incorporated cities, including the City of Los Angeles. The City of Los Angeles’ establishes its own storm water program, which is a part of the Department of Public Works. The Stormwater Management Division within the Bureau of Engineering is formed and is responsible for the development and implementation of storm water pollution abatement projects and programs.


The Porter-Cologne Water Quality Act mandates water quality standards for surface and groundwater in California, requiring states to establish a priority ranking for impaired waters and to develop and implement Total Maximum Daily Loads (or TMDLs).


The City of Los Angeles adopts a storm water ordinance (L.A.M.C. 64.70) which prohibits the entry of illicit discharges into the municipal storm drain system and gives the City local legal authority to enforce the NPDES Permit and take corrective actions with serious offenders. Any commercial, industrial or construction business found discharging waste or waste water into the storm drain system may be subject to legal penalties.


Courts issue a consent decree requiring municipalities to be in compliance with all NPDES Permit-mandated Total Maximum Daily Load (i.e. the maximum amount of a pollutant that a body of water can receive while still meeting water quality standards) requirements within 13 years.


The Los Angeles Regional Water Quality Control Board adopts a Los Angeles municipal storm water permit, including Total Maximum Daily Load (TMDL) implementation requirements.


US Environmental Protection Agency begins approving various TMDLs for multiple watersheds including trash for LA River and Ballona Creek, wet and dry weather for Santa Monica Bay Beaches and bacteria for Marina del Rey Harbor and Mother’s Beach, among others.


Los Angeles voters pass Measure O, a general bond measure that authorizes $500 million in bonds to build capital improvement projects designed to address the regulatory requirements of the federal Clean Water Act and improve water quality, protect public health and the environment. Measure O helps to provide funds for TMDL compliance and projects to remove trash, bacteria and other pollutants from local rivers, lakes, beaches and the ocean.


The City of Los Angeles adopts the Los Angeles River Revitalization Master Plan.


The City of Los Angeles adopts a Low Impact Development ordinance, which amends L.A.M.C. 64.70 and requires development and redevelopment projects to mitigate runoff  by capturing rainwater at its source utilizing natural best management practices such as rain barrels, permeable pavement, cisterns and infiltration swales.


After a multi-year $45 million Proposition O-funded restoration, Echo Park Lake, the crown jewel of LA’s lakes, re-opens.


Los Angeles County voters pass Measure W, the Safe, Clean Water Act, which will provide funding for projects, infrastructure and programs to capture, treat and recycle rainwater. 

Photo courtesy of Water and Power Associates.