Stormwater Related Information for Landscaping Industry

Preventing landscaping activity runoff from entering our streets and storm drains helps protect our waterways from pollution!  All sources of pollution, including landscaping activity runoff, are prohibited from leaving your property and entering streets or storm drains. Only rainwater is allowed in the streets and storm drains.

Did you know…

  • Landscaping activities can generate pollutants such as fertilizers, pesticides, and organic wastes. These pollutants can be washed into our streets and storm drains and enter waterways as a result of over irrigation or rain events where they degrade our water quality and harm aquatic life. 

  • Leaves, soil, and yard trimmings that are not responsibly disposed of are also water polluters. These pollutants reduce water oxygen levels, block light, inhibit photosynthesis, cause flooding, and promote algae blooms.

  • Releasing pollutants directly or indirectly into the storm drain system is a violation of the County’s Watershed Protection Ordinance (WPO)


What can I do?

  • Dispose of waste thoughtfully: rake up lawn clippings, leaves, and other yard waste and dispose of them in green waste bins. Alternatively, drop-off yard trimmings to facilities that will compost them into a beneficial compost or mulch. These facilities are often much less expensive than taking the materials to a landfill. To locate a facility near you, visit


  • Use Best Management Practices (BMPs) for your business: BMPs are techniques or controls used to prevent or reduce the discharge of pollutants, such as yard waste or chemicals, into the storm drain system. BMPs for a landscaping business include scheduling excavation projects for dry weather, using organic or nontoxic fertilizers (learn more about these practices here) or ensuring that sprinkler heads are positioned to water the plants and not the sidewalk.


Want to learn more?

The resources below provide suggested BMPs and further information on how to protect our waterways. Click the buttons to view available languages:  

How to Hire a Landscaper Webinar presented by The Water Conservation Garden


Composting and Manure Management
General Pollution
Inspect Your Business
Materials Management Spill Response
Train Your Employees
Loading and Dumpster Areas

Know before you go…

Cover stockpiles of soil with plastic to avoid soil ending up in our storm drains.


Contact Us

If you would like to report a concern regarding landscaping activities, have questions about our program, or would like additional information call the County Storm Drain Pollution hotline at: 1(888) 846-0800 or e-mail us at 


Thank you for doing your part to protect our waterways!