Frequently Asked Questions

Whom do I call to report a clogged catch basin, flooded streets or illegal dumped materials in the public right-of-way?

In an emergency, where the public health and safety is in danger, please call 9-1-1. In all other situations, call the Stormwater Hotline at (800) 974-9794.

What is storm water pollution?

Storm water pollution is when water from rainstorms, garden hoses and sprinklers causes runoff that collects harmful debris and flows through local creeks, rivers and lakes -  eventually draining, untreated, into the ocean.

What is a watershed?

A watershed is an area of land that collects water whenever it rains or snows. Through gravity, water is channeled into soils, groundwater, creeks, and lakes and drains into larger bodies of water such as rivers. Eventually, the water flows to an ocean. We all live in a watershed, and whatever we do to the land will affect water quality downstream.

Los Angeles is located in four watersheds - Los Angeles River, Ballona Creek, Dominguez Channel and Santa Monica Bay. The water from these four watersheds flows into San Pedro and Santa Monica Bays and ultimately into the Pacific Ocean.

How much water flows through Los Angeles’ storm drain system?

Even on the driest day in Southern California, tens of millions of gallons of contaminated water and debris flow through our local creeks, rivers and lakes and into Santa Monica and San Pedro Bays.  On a rainy day, the flow can increase to as much as 10 billion gallons.

Is storm water treated before it flows to the ocean?

No. Storm water flows do not receive any treatment because of the sheer volume of runoff – tens of millions of gallons on even the driest day – from an area encompassing more than 1,000 square miles.

What’s the difference between a storm drain and a sewer drain?

Here in Los Angeles, the sanitary sewer system and the municipal storm drain system are two completely separate water drainage systems.

The sanitary sewer system takes waste water from toilets, showers and sinks and routes it to one of several waste water treatment plants here in Los Angeles. Once there, it receives multiple levels of treatment before being discharged into the ocean.

Every day tens of millions of gallons of urban runoff – enough to fill the Rose Bowl – flows through our local waterways.

LA’s storm drain system, which was built in the 1930s and 40s to prevent flooding, carries excess water from rain, sprinklers or business activities away from city streets and straight out to the ocean. Every day, tens of millions of gallons of urban runoff – enough to fill the Rose Bowl – flows through our local waterways. The system is unable to treat the water due to the sheer volume of runoff and it now serves the unintended purpose of carrying pollutants such as used motor oil, paint, trash, pet waste, and pesticides through our local rivers, creeks and lakes, and into our local bays.

What are the effects of storm water pollution?

Along the coast, storm water pollution poses a health risk to beach goers swimming or fishing in the Santa Monica and San Pedro Bays, particularly within 400 yards of flowing storm drain outlets. Countless marine animals and plants living in the Santa Monica and San Pedro Bays can become sick or die from contact with pollutants in urban runoff.

In inland communities, catch basins clogged with pollutants can significantly decrease the quality of life in many neighborhoods through Los Angeles. Nests of trash and debris can attract vermin and create foul odors, negatively impacting neighborhood aesthetics and property values and creating the potential for flooding during rainstorms.

What is the City of Los Angeles doing to improve water quality in our local creeks, rivers, lakes and beaches?

The City of Los Angeles’ award-winning Stormwater Program employs a comprehensive approach, utilizing education, engineering, enforcement and evaluation to ensure the City’s compliance with federal, state and local regulations and reduce the amount of storm water pollution flowing into and through regional waterways.

Education – Los Angeles’ public education program utilizes school outreach, targeted point-of-purchase advertising, community events, engaging education materials and online social marketing components that include a Facebook page, blog and quarterly e-newsletter to educate Angelenos about the importance of keeping pollutants out of our local creeks, rivers, lakes and beaches.

Engineering – The planning and implementation of capital improvement projects that capture trash, clean up urban runoff and retain storm water for beneficial uses is one component of the City’s program. Funding from various federal, state and local grants as well as voter-approved Proposition O provides for the construction of projects which range from the rehabilitation of local lakes to the upgrade of coastal low-flow diversions - from  the installation of catch basin opening covers to green infrastructure projects. Collectively, they all work to keep pollutants out of local waterways.

Enforcement - A team of environmental compliance inspectors enforce the City’s Stormwater Ordinance (LAMC 64.70) by conducting site visits to more than 10,000 business and commercial facilities annually, responding to and mitigating reports of illicit discharges and connections to the storm drain system and overseeing the remediation efforts associated with abandoned hazardous waste and spills.

Evaluation – The City evaluates urban runoff pollution issues in four local watersheds – Los Angeles River, Ballona Creek, Dominguez Channel and Santa Monica Bay. Each year, the program collects thousands of samples from open channels, coastline and the ocean, conducting tens of thousands of analyses used to evaluate the impact of pollutants on the City’s water bodies.

Ensuring Compliance - The City complies with mandates outlined in the National Pollutant Discharge Elimination System (or NPDES) Municipal Storm Water Permit (No. CAS004001), which includes working with stakeholders in the development and adoption of achievable Total Maximum Daily Load (or TMDL) regulations as well as the creation of monitoring and implementation plans for adopted TMDLs within the City’s four watersheds and impacted water bodies to ensure compliance.

How can I help keep my neighborhood and local waterways pollution free?

Getting involved is a great way to keep your neighborhood and local waterways clean. Here are a few simple ways to help keep pollutants out of local water bodies:

  • Participate in or organize a local neighborhood clean-up.
  • Educate your friends and family about the impact pollutants have on water quality.
  • Reduce, reuse and recycle.
  • Always use canvas bags when shopping.
  • Consider installing a rain barrel on your property to harvest the rain. It’s a great way to save money and conserve one of our most precious natural resources!
  • Visit our calendar for information about beach clean-ups, ocean-friendly gardening classes and more!