American Canyon's focus on stormwater ensures water quality in the Napa River watershed remains high by reducing the potential for flooding, erosion, and various types of water pollution. To more effectively reduce stormwater pollution in the Napa River watershed and to provide a consistent approach to stormwater regulations, American Canyon and the other Napa County municipalities formed the Napa Countywide Stormwater Pollution Prevention Program. Bringing together countywide talents, knowledge and skills, we all benefit in providing community outreach and education programs, creating regulatory guidelines for construction contractors, and in obtaining grant funding to support specific parts of our programs.

What is Stormwater?

Stormwater is runoff or the draining away from rain that flows off of streets, properties, and rooftops into storm drains. Water travels from storm drain systems directly into local creeks and ultimately out to the Napa River and San Francisco Bay.

In American Canyon wastewater and stormwater are two completely separate systems. Unlike wastewater, stormwater receives no treatment before it reaches our local waterway. The lack of treatment of this water requires us to take extra precautions to keep our creeks and other bodies of water clean and safe.

The quality of the water entering our storm drains can have an extreme impact on our environment.

Construction Projects

All individuals undertaking public or private construction or ground disturbing activities must take steps to prevent discharge of pollutants resulting from these activities. To find out what level of Best Management Practice (BMP) implementation is required for a project, applicants may refer to the Stormwater Quality Submittal Requirements Checklist for applicability. Projects that disturb less than one acre (<1 acre) of soil may refer to the Erosion and Sediment Plan Guidance. Projects that disturb more than one acre (>1 acre) of soil are subject to the state's Construction General Permit (CGP). These projects must apply for and comply will all requirements of the CGP.


Leaves & Yard Trimmings

The number one cause of street flooding? Leaves!

Yes, leaves ending up in the gutter and storm drain inlets is the most frequent cause of flooding in American Canyon – and you can help keep the rain flowing on your own street. How?

Don’t blow, rake or pile your own leaves in the gutter. Sometimes neighbors don’t see the harm in blowing leaves into the gutter or across the street. Resist the temptation! Blowing leaves into any gutter will cause flooding!

The street sweepers you see coming by your home can’t pick up big piles of leaves. Recology American Canyon provides Yard Waste Bins so you can conveniently dispose of leaves as you rake, and then they are composted to make new soil - No Waste!

A less obvious problem with putting leaves in the gutters shows up as the leaves make their way to the Napa River. Storm-water, unlike the water leaving your house through the drains in the sink, toilets and tubs isn’t treated before it makes its way to the River. When leaves get into the River, they change the water temperature and absorb oxygen as they breakdown, stressing our wildlife’s ability to survive – and wet leaves make great breeding grounds for those pesky mosquitoes.

You may see our Public Works Crews out on the streets preparing for the wet season storms on the not-to-distant horizon, working with big equipment that vacuums out the storm drain inlets. But for neighborhoods with a lot of leaf fall and where neighbors put leaves in the gutters, you’re likely to see them out in the rain with rakes and shovels and Road Closed signs because the leaves clog the drains repeatedly and cause walkway and driving hazards. Don’t let your street be one of those flooded zones!

Disposing of leaves in the gutters and storm drain inlets is a violation of American Canyon’s Municipal Code 14.28 (Storm-water and Pollution Discharge Control Program).

You Can Help Prevent Flooding on Your Street – Use Your Yard Waste Bin!



You can do your part to help protect our local water resources by following Do's and Do Not's:

Stormwater Do's

Pick up and dispose of pet waste in trash (not green waste)

Direct your sprinklers away from driveways and sidewalks.

Sweep the gutters and driveways regularly and place the sweepings in your garden or green waste

Rake up leaves or lawn clippings and use them as mulch on the garden or place them in the compost

Dispose of paint and chemicals at approved disposal sites

Maintain your car, making sure there are no leaks and that fuel is burnt cleanly

Use the minimum amount of detergent for cleaning outside, and wash your car on the grass or on gravel

Take your car to a car wash, where the water is recycled

Stormwater Do Not's

Work on your car in a place where oil and grease may wash into gutters

Hose dirt off hard surfaces (roads, paths, driveways) into gutters

Hose leaves and grass clippings into gutter

Pile sand and soil on areas where it can wash into the stormwater system

Overuse pesticides and herbicides that could be washed into stormwater from the garden or yard

Put anything in a storm drain - only rain goes in the drain.