Storm drains are gateways that allow pollutants in stormwater to flow untreated from local streets to lakes, rivers and streams. Residual oil, grease, solids, antifreeze, cigarette butts, yard waste, plastic and other wastes found on roads, parking lots and driveways pollute downstream waters by increasing phosphorus levels, reducing oxygen levels and ultimately impairing aquatic habitat for fish and other organisms as well as drinking water sources.
An unfortunate, yet still common, misperception is that storm drains discharge to water treatment plants. Stenciling is one public education tool that helps dispel this misperception. This fact sheet provides guidance on implementing a storm drain stenciling program to increase public awareness of the direct connectivity between storm drains and water resources.
Storm drain stenciling will help the people in your community understand what happens to polluted stormwater. When people are aware of the negative environmental impacts of their actions, they are more likely to stop dumping pollutants down storm drains. Reduction in the discharge of pollutants into storm drains results in cleaner downstream lakes, streams and wetlands. It contributes to improved water clarity, coloration and odor as well as fish and wildlife habitat.
Programs designed to increase public awareness through volunteer efforts have the benefit of educating both the general public and the volunteer. The extent of an MS4’s storm drain stenciling program is dependent upon several factors including the MS4’s available resources, size of staff, and degree and character of its illicit storm drain discharges. Many pollution prevention awareness phrases can be effective: “No Dumping. Drains to River,” “No Dumping. Drains to <Insert Water Source>,” “You Dump It, You Drink It,” “No Waste Here,” and “Only Rain in the Drain.” For more information regarding other methods to trace and prevent illicit discharges see the Potential Discharge Identification and Risk Reduction fact sheet.
Storm drain ‘stenciling’ can be done with paint and stencils, medallions, pre-stamped grates or stamped concrete.
Paint Painting or spray painting with a paper, plastic or metal stencil as a guide is an inexpensive application for storm drain stenciling and easily implemented by volunteers. However, the lifetime of the paint may not exceed two years. Stenciling can be done on the street in front of the storm drain, on the adjacent sidewalk, or on the curb. Spray paint is the easiest to apply neatly, but contains air polluting propellants. Consider using environmentally-friendly paints free of heavy metals and low in volatile organic compounds.
Medallions Plastic, ceramic or metal medallions, typically 4 inches round, can be glued with a strong epoxy or embedded in concrete and bolted down. Gluing medallions is easily transferrable to volunteer programming.
Pre-stamped grates Pre-stamped grates will last a long time (until the metal is worn down) and are an effective means to implement a city-wide storm drain stenciling initiative.
Stamped concrete While concrete is still wet, stamp an impression of the selected ‘no dumping’ slogan. Stamped concrete will last longer than paint or medallions. In addition, concrete stamps allow versatility in design since, unlike medallions, long-term stability is not based on size of the design.
Encourage organization-sponsored stenciling Storm drain stenciling is a great activity for all types of organizations including service clubs, neighborhood associations and scout groups. Stenciling does not require extensive volunteer participation. A few trained volunteers can thoroughly mark storm drains within a single neighborhood. However, the educational nature of the activity facilitates greater understanding among participants of the value of water resources.
MS4s can provide brochures and guidance documents identifying how to stencil and recruiting organizations to get involved. The City of Lakeville, MN, provides an online sign-up form for individuals and organizations to get involved. The City of Woodbury, MN, recruits community groups for storm drain stenciling projects. Volunteers also distribute informational door hangers to homes in the project area. A single project area is a commitment of one to two hours of work. In all cases of recruiting volunteers, the City provides materials and instructions. Friends of the Mississippi River, University of Minnesota Extension Service and North Carolina State University are just a few of the entities that provide detailed guidelines on volunteer safety, protection of public and private property, MS4 liability, painting quality and stenciling effectiveness.
Adopt A Street integration The City of Ashland, Oregon, has instituted a storm drain stenciling program in collaboration with their Adopt a Street Program. They encourage participants in the existing Adopt a Street Program to stencil storm drains as well. The same collector or arterial street adopted for quarterly trash pick-up by businesses, organizations or schools can serve as the site to conduct storm drain stenciling with City resources.
Be prepared The EPA suggests that organizers be prepared with the following at all volunteer stenciling events:
Require that all new and repaired storm drains be outfitted with storm grates that have a pre-stamped pollution prevention message such as “No Dumping, Drains to River.” The City of South Jordan, Utah provides a good example of engineering specifications for storm drain stenciling:
Developments must provide theft-resistant permanent installation of a City-approved storm drain marker at each stormwater inlet. The marker is part #STDM-9131-SSP, a 4” Stainless Steel Green Painted Marker with Custom Tree Logo with ¼” square hole made by Almetek Industries, Inc. Installation requires Drive Rivet and approved adhesive. Lettering on the marker as appropriately follows:
Specifications such as this could be contained in MS4 drainage manuals, stormwater design manuals, engineering guidelines, or stormwater management ordinances and permitting.
In order to maintain the visibility of the storm drain stenciling, re-application may be necessary. Painting lasts about 2 years while medallions would not require replacement for many years, depending on the application.
The EPA indicates that plastic stencils that can last 25 to 500 uses, depending on paint application (spray, brush, or roller), cost 💲10 to 💲15.50. Metal stencils have the benefit of lasting longer and can cost 💲100 or more. Medallions range from 💲1 to 💲💲3 for 4-inch diameter plastic markers, 💲2 to 💲5 for metal and up to $7 for ceramic. Costs vary based on custom versus standard designs. Glue is only a fraction of the cost. A one-time set-up fee of 💲200 to 💲1,000 for pre-cast drain inlets with custom pollution prevention messages is applicable above the cost of the structures based on the text and or imagery of the message. Concrete stamps cost around $100 depending on size and custom versus standard designs.