What is stormwater runoff?
Stormwater runoff occurs when rain and snow melt runs off the landscape and manmade surfaces. Impervious surfaces such as sidewalks, streets, highways, and parking lots prevent stormwater runoff from soaking naturally into the ground.
Why is stormwater runoff a problem?
- Untreated stormwater from all sources is a major threat to Puget Sound and to the state’s urban waters. If left untreated, water running off impervious surfaces, can pick up oil, fertilizers, pesticides, soil, trash, and animal waste. It can carry these pollutants downstream into lakes, river and marine waters.
- Stormwater runoff from farm fields, lawns and other intensively managed landscapes can also contribute to the polluting effects of stormwater.
- Uncontrolled stormwater can also erode soil and stream channels, produce muddy water that may suffocate salmon and salmon egg nests, and harm habitat for other aquatic life.
- It can also cause flooding and slope failures that threaten people’s homes.
Why is the Washington State Department of Transportation (WSDOT) concerned about stormwater?
Paved surfaces, such as highways and ferry terminal holding lots, do not allow water to penetrate into the ground where it can be naturally filtered and cleansed before it enters streams or underground water supplies. Federal and state regulations require that WSDOT have permit coverage in many locations where stormwater is collected, conveyed and discharged into waterways. These locations include:
- Highways
- Ferry terminal facilities
- Park and ride lots
- Maintenance shops and yards
- Rest areas
Statewide, WSDOT has approximately 40,000 acres of paved surfaces. Managing the stormwater that comes from our transportation facilities helps fulfill our environmental stewardship commitment and regulatory permit requirements.
What is a stormwater municipal permit?
As part of the federal Clean Water Act, Congress established the National Pollution Discharge Elimination System (NPDES), which requires many who discharges stormwater into surface waters have a “permit.” Under the NPDES, pipes, ditches, and other conveyances that carry runoff from state highways and related facilities are considered municipal storm sewer systems. Therefore, WSDOT is required to have a municipal stormwater permit for many of its facilities. In Washington, the Department of Ecology (Ecology) is the delegated authority to issue and administer the permits.
Ecology and the federal Environmental Protection Agency use a permit system to establish management practices for air, water and land. For stormwater, these management practices protect human health and the environment. They are guideposts that allow us to manage stormwater to protect beneficial uses, such as swimming, drinking water, recreation, and marine habitat.
What has WSDOT done about managing stormwater?
Originally, the focus of WSDOT's highway stormwater management was maintaining safe driving conditions and the integrity of the highway. Since 1995 WSDOT has had permit coverage for some state highways and other transportation facilities under Ecology’s Phase I municipal stormwater general permit. Phase 1 permits include the state’s most populated areas in Clark, King, Snohomish and Pierce counties. These permits require that highways be designed and maintained to minimize pollution and potential damage to stream banks and downstream properties. The permit also describes what types of monitoring and reporting WSDOT must perform.
Under the Phase 1 permit, WSDOT has been managing stormwater from new impervious surfaces statewide since the late 1990’s. In addition, in 1997 WSDOT prepared its own Stormwater Management Plan that outlines its strategy for protecting water quality and complying with federal and state laws. WSDOT prepares an annual report that describes the progress and stormwater-related activities within the permit coverage area. These reports are available on the Web at: http://www.wsdot.wa.gov/Environment/WaterQuality/default.htm#reports
Why is WSDOT asking for its own stormwater permit?
As Ecology was preparing to re-issue the Phase I permit, WSDOT was faced with a decision whether to continue coverage under the Phase I and Phase II (for populations of at least 10,000) general municipal stormwater permits, or apply for its own permit. The general permits are developed primarily for municipalities and the variety of land uses typically associated with urban areas. WSDOT chose to apply for its own permit, and Ecology concurred, because they felt that a WSDOT-only permit would be a better fit for the highway system and the nature of its operations.
What are some of the ways WSDOT manages stormwater?
WSDOT uses best management practices (BMPs) for controlling and managing stormwater. These are the structural devices, maintenance procedures, management practices and activities used to prevent or reduce the harmful effects of stormwater runoff, such as pollution, erosion and flooding. BMPs may include:
- Structural features such as detention and infiltration ponds, wide grass swales, catch basins, and vegetated filter strips
- Maintenance operations to keep highways cleaned of sand, litter and debris that could make its way into streams and rivers
- Vegetation management practices along highways and other transportation facilities to reduce the use of herbicides
- Management practices such as reducing the use of sand and increasing monitoring and maintenance of structural BMPs.
- Staff training on methods for controlling stormwater and preventing pollution
What effect will the new permit requirements have?
Most of Washington’s highway infrastructure was built before federal Clean Water Act requirements came into play. This means, while new highways and highway features are built to current standards and manage runoff, many of the older, existing highways will need to be upgraded to conform to current stormwater requirements and standards.
This permit will require that WSDOT expand its current stormwater management program over a larger geographic area and increase monitoring and reporting efforts. Both Ecology and WSDOT expect this permit to require a significant increase in resources and funding. Some of the changes will include:
- Increased inspections and maintenance of existing stormwater features
- Expanded monitoring – both for the type and amount of pollution found in stormwater runoff and the effectiveness of best management practices
- New reporting requirements – an annual report to Ecology will be due each year to include performance assessments as well as monitoring data.
How much will these new requirements cost to implement?
The Governor’s transportation budget for the 2009-2011 biennium included $1.5 million to begin implementing the requirements of the municipal stormwater permit. The true costs of meeting the permit requirements cannot be accurately indentified until WSDOT has completed mapping and inventory of its facilities and gained additional experience with maintaining these stormwater management facilities.
WSDOT has been working with the legislature to secure 2009 - 2011 funding resources to begin carrying out the requirements of the new stormwater permit. Future projections for the 2011 – 2013 and 2013 – 2015 biennia indicate that costs to implement the new stormwater permit will significantly increase over the ’09-11 levels.
Do other states have their own stormwater permit?
Yes, several other state departments of transportation have their own NPDES municipal stormwater permit, including Caltrans and Colorado DOT.
What can I do to help?
Pollutants that may run off the highway are generated from motor vehicle “wear and tear” and emissions as well as particle-laden smokestacks. Untreated pavement runoff can carry these pollutants to water bodies. You can do your part by:
- Keeping your vehicle properly maintained – fix those drips and leaks and tune your vehicle’s engine
- Choosing to leave your vehicle at home – fewer vehicles on the road mean less congestion and idling, less vehicle residue and cleaner air due to reduced emissions – try transit, carpools, telecommuting, walking, or bicycling
- Using a vehicle trash bag and securing your loads – litter on roadways can end up in waterways – don’t toss trash from your vehicle and make sure the loads you haul won’t blow out the back
- Consider purchasing a low emission vehicle when it comes time to replace your existing car – vehicle emissions contribute to the pollutants found in stormwater runoff
- Parking your vehicle and going inside to purchase your latte or fast food – idling vehicles at drive-ups contribute to pollutants that find their way into stormwater runoff
- Picking up after your pet at rest areas and along roadways – organic materials contribute to stormwater runoff pollution
Directions for how to report a spill or illicit discharge can be found on the Stormwater and Watershed Program website.
Where can I get more information about stormwater regulations?
Who can I contact for more information?
Larry Schaffner, WSDOT, 360-570-6657; schaffl@wsdot.wa.gov
Foroozan Labib, Department of Ecology, 360-407-6467; flab461@ecy.wa.gov