NPDES Stormwater Permit
- NPDES Stormwater Permit
- Stormwater Management Plan
- Public Education
- Stencil a Storm Drain
- Adopt a Drain
- Illicit Discharges and Spills
- Private Storm Drainage Maintenance
- Low Impact Development (LID)
National Pollutant Discharge Elimination System (NPDES)
The NPDES permit requires the City to take numerous actions to reduce the amount of polluted surface and stormwater runoff flowing into our creeks, streams, rivers, and groundwater. This Permit is issued to the City by the Washington State Department of Ecology and satisfies a mandate within the Federal Water Pollution Control Act of 1948. Due to growing public awareness and concern it was amended in 1972 and is now commonly known as the Clean Water Act (CWA).
This permit requires the city to:
- Provide Outreach and Education: work with people and businesses to promote daily activities that reduce stormwater pollution.
- Inform and involve the public: give people the opportunity to weigh-in on how we meet permit requirements.
- Respond to spills and seek out cross-connection pipes: this activity is called an "illicit discharge detection and elimination program (Spill Response).
- Review development projects: ensure stormwater facilities are built to City standards, and that construction activities don't pollute stormwater.
- Inspect and maintain public facilities: inspect and clean infrastructure, and make repairs if necessary.
- Inspect and ensure private facilities are maintained: inspect private facilities and ensure property owners maintain and make repairs if necessary.
NPDES Municipal Stormwater Permit
Learn More! Water Cycle Glossary of Terms
Small Actions Add Up to Big Change
Our actions within our watershed have a direct impact on our wetlands, creeks, streams, lakes, the Snoqualmie River, and the Puget Sound. The City of Duvall and local environmental groups are making a significant effort to restore the local environment and protect our remaining aquatic habitat.
Keep water safe and clean by preventing pollution at its source. Stormwater run-off carries oil and grease, fertilizers, pesticides and other toxic chemicals that collect on our roads, rooftops, and property. What we do on the land ends up in the water. You can help keep our waters healthy by planting trees, scooping up at your pet, or stenciling a storm drain or adopting a storm drain.
Please continue reading for ways on how you, as a Duvall resident, visitor, or business owner, can make a difference where you live and where you work.
The city encourages public comment and participation in the development and implementation of the SWMP. We plan to utilize the following venues in an effort to keep our residents informed on the progress of the SWMP, so they can provide comments and input as the SWMP develops:
Stormwater Runoff Awareness, Attitudes & Behavior Survey Results (2019)
Residential Car Washing and Stormwater
|When a car is washed on a paved surface, like in a driveway or in a parking lot, the soap, detergent, automotive fluids, oil, heavy metals, and roadway dirt that are rinsed from the vehicle goes straight into nearby storm drains. Storm drains convey water to the nearest river or stream without treatment. This contaminated runoff, even runoff containing biodegradable soap, can cause significant harm to aquatic plant life, fish, and other animals.|
You can wash your car and prevent stormwater pollution if you:
|Car Wash Kits|
The City of Duvall is no longer providing Fundraising Car Wash Kits. The Car Wash Kit was intended to prevent pollution from entering our storm drainage system, which drains to our local streams and the Snoqualmie River. Studies show that fundraising car washes still may allow soap and dirty wash water to flow to storm drainage systems. Since State and Federal regulations make it illegal to dump any wastewater to the storm drainage systems, public or private, the City of Duvall asks that you check out these alternative fundraising ideas as alternatives to holding a car wash.
Contact the City of Duvall by email if you have any questions.
Stencil a Storm Drain
Request a Stencil Kit
Find Your Storm Drain
Next Steps to Clear a Storm Drain
Our actions within our watershed have a direct impact on our lakes, streams, wetlands and the Puget Sound. The City of Duvall and local environmental groups are making a significant effort to restore the local streams and protect our remaining aquatic habitat. Please do your part in keeping our waterways healthy by helping us keep an eye out for illegal activity which can damage water quality.
How can you help?
Reporting Discharges & Spills
Please do your part in helping to protect our natural waterways. Report any spill, illicit discharges or illicit connections to our natural waterways or storm system by calling the city’s spill hotline. City staff understands the need for confidentiality, so calls can be anonymous. However, please provide as much detail as possible about the spill or illegal activity including the date, time, location, a description of the spill or illegal activity and a description of the pollutant.
All city storm drains flow into natural waterways. So it is very important to report illegal dumping or even accidental spills in our roadways, storm systems or natural waterways.
Illicit DischargesAn illicit discharge to a stormwater system is the discharge of pollutants or non-stormwater materials to storm systems via overland flow or direct dumping of materials into a storm drain. Some examples of illicit discharges include run-off car washing or dumping motor oil, antifreeze or paint in or around a street or storm drain.
Illicit ConnectionsAn illicit connection to a stormwater system is the discharge of pollutants or non-stormwater materials into a storm system (pipes, catch basins, ditches, etc.) via a pipe or other direct connection. Sources of illicit connections may include sanitary sewer taps, wash water from laundromats, car washes, or restaurants and other similar sources.
Private Storm Drainage System Maintenance
The City of Duvall requires property owners to inspect and maintain stormwater systems on their private property. The City inspects private stormwater systems to ensure that they are functioning properly. It is important that property owners maintain these systems to prevent pollutants from entering the drainage system and surface waters of Duvall.
Stormwater systems are designed to collect and control runoff, prevent flooding, and keep pollutants out of surface waters. This benefits everyone by providing safe use of City streets and clean recreational waters to enjoy. Regular maintenance on storm system catch basins, ponds, and ditches is not time consuming or difficult. Contact information for the Storm Utility and the City's minimum maintenance standards are below.
City of Duvall Maintenance Guidelines
All private storm systems are required to meet the Maintenance Standards for Drainage Facilities found in Volume V of the Washington State Department of Ecology (Ecology) Stormwater Management Manual for Western Washington (SWMMWW) found here: Ecology SWMMWW Maintenance Standards for Drainage Facilities.
For more information about your private stormwater management system, state and local requirements, and the City's Storm Utility please email us.
Low Impact Development (LID)
The low impact development approach to developing land and managing stormwater is to imitate the natural movement of water through a site.
Where forests and natural open spaces have been cleared, and buildings, roads, parking areas and lawns dominate the landscape, rainfall now becomes stormwater runoff, carrying pollutants to nearby waters.
The City has developed a Homeowner's Guide to LID Best Management Practices.
The City of Duvall welcomes comments and feedback on our current Stormwater Management Program. After reviewing the documents and information please provide your feedbackby clicking on the feedback button below. Be as detailed as possible, we value your input!
SWMP Annual Reports
2023 Submittal Certification
2022 Submittal Certification
2021 Submittal Certification
2020 Submittal Certification
2018 Submittal Certification
2017 Submittal Certification
2016 Submittal Certification
2015 Submittal Certification