Storm Drains

Program Description
Storm drains are designed to prevent flooding. Water that enters our storm drains is not treated before it enters into our creeks and eventually the ocean. The City is required by the Clean Water Act to comply with a Stormwater National Pollutant Discharge Elimination System (NPDES) permit issued by the State. The Stormwater Quality Management Program implements this Federal mandate to reduce the amount of pollution that enters our storm drain system.

To view a copy of the Countywide NPDES Municipal Stormwater Permit, visit Ventura Countywide Stormwater Quality Management Program.

Important Notice about Saltwater Swimming Pools and Spas

Did You Know...

Your kitchen sink and a storm drain are not connected. These two systems are completely separate. The water that goes down a sink or toilet flows to a wastewater treatment plant where it is treated and disinfected before being reintroduced to the environment. However, water that flows down your driveway and into a gutter goes down a storm drain which flows untreated directly to a creek or lake, and eventually to the ocean. The water that goes down storm drains is not treated to remove harmful bacteria or pollutants.

Almost anything but clean rain water is considered a pollutant when it enters a storm drain. Some common contaminants in stormwater include pet waste, pesticides, paint, and household chemicals like soap and fertilizer. Products advertised as "non-toxic" or "biodegradable" are not typically safe for the environment either. Even dirt entering the storm drains can cause problems for the environment.

Small amounts of pollutants can be harmful. Small amounts of pollution add up to a big problem when it comes from an entire city. Those small amounts of pollution coming from everywhere in the City can have harmful effects on drinking water supplies, recreational use, and wildlife.

Even animals can cause stormwater pollution. Pet waste is more than a neighborhood nuisance, it contains bacteria which may cause illness. When pet waste is not picked up, rain and sprinkler runoff carry the bacteria across lawns, into streets and gutters, and then down a storm drain which leads directly to our local creeks and eventually to the ocean.

For more information, visit The Poo-lution Solution - More than a Neighborhood Nuisance

You can prevent stormwater pollution.
Preventing stormwater pollution is simple. Follow these tips and ask your friends and family to do the same.

  • Don't dump litter or waste on streets or in storm drains.
  • Keep yard trimmings and leaves out of the street.
  • Dispose of household chemicals properly.
  • Pick up after your pet and dispose of waste in a trash can.
  • Clean up oil spills and fix leaking automobiles.
  • Sweep driveways and sidewalks clean - do not hose them down.

Don't Dump - It's the law.
City Ordinance makes it illegal to dump or allow anything but clean water, with few exceptions, to go down a storm drain. If you would like to read the Ordinance, visit Thousand Oaks Municipal Code click on Title 7 on the left, and then Chapter 8 on the right.

The same laws that require the City of Thousand Oaks to control the amount of pollutants entering their storm drain systems also require large construction sites and some industrial facilities to minimize the amount of pollution coming from them.

Industrial facilities and construction sites are regulated by the State Regional Water Quality Control Board through general stormwater permits. For more information on State Stormwater Permits, visit the State Water Resources Control Board's website.

Call us to report a polluter.
It is illegal to allow any pollution down a storm drain. If you know of a situation where pollution may enter the storm drain, call the Public Works Department at (805) 449-2400.

To report a storm drain that is clogged or otherwise in need of maintenance, please call (805) 449-2499.

Volunteer Opportunities
If you or your group would like information on creek cleanup events and other ways you can help the environment, please call (805) 449-2386, or click here to request more information.

For more information on stormwater pollution or stormwater drainage, please visit:

For additional information on other environmental programs, visit City of Thousand Oaks Environmental Programs