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THE BASICS
WHY IS STORMWATER RUNOFF A PROBLEM?
HOW DO YOU MANAGE STORMWATER RUNOFF?
WHAT CAN YOU DO TO REDUCE STORMWATER POLLUTION?
LINKS TO STORMWATER MANAGEMENT PROJECTS IN OTHER COMMUNITIES
REFERENCES

THE BASICS:

Stormwater is rain, snow or sleet that is a direct result of precipitation, which flows in both concentrated forms (pipes, gutters, ditches, streams, etc.) and diffuse forms (sheet flow) over or within all land forms. Stormwater soaks into the soil and becomes groundwater, is used by vegetation, evaporates, or flows into lakes or streams as surface flow. Stormwater collects pollutants and debris as it travels to our local waterways.

Stormwater runoff is rain or melting snow that cannot soak into the ground, and instead flows from the land into nearby waterbodies. Stormwater runoff is not treated in any way.

Nonpoint source pollution is another term for polluted stormwater runoff and other sources of water pollution whose sources are hard to pinpoint. The term comes from the federal Clean Water Act of 1987.

Impervious surfaces are hard surfaces that prevent stormwater from soaking into the ground. Where there are more impervious surfaces in a watershed, stormwater runoff enters local waterbodies in greater volumes and at faster speeds. Examples of impervious surfaces include paved streets, sidewalks, parking lots, driveways, and building rooftops.

A watershed, also called a drainage basin, is the area of land that drains into a body of water. Watersheds come in all shapes and sizes, and cross county, state, and national boundaries. Smaller watersheds (e.g., Spring Lake watershed), may be part of a larger watersheds (e.g., Lower Grand River watershed), which may be part of an even larger watershed (e.g., Lake Michigan watershed). No matter where you are, you're in a watershed. To find out which watershed you are in right now, visit: https://cfpub.epa.gov/surf/locate/index.cfm.

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WHY IS STORMWATER RUNOFF A PROBLEM?

Water pollution: As stormwater runoff flows from the land and into streams, rivers, and lakes, it can be contaminated with a number of substances such as:

• Sediment from construction sites and eroding stream banks
• Organic materials such as grass, lawn clippings, and leaves
• Oil and gasoline from boats, automobiles, and storage tanks
• Nutrients such as phosphorus and nitrogen from fertilizer
• Pesticides from lawns, gardens, agricultural fields, and golf courses
• Pathogens such as bacteria and viruses from pet waste, failing septic systems, farm animals, and wildlife
• Trash and street garbage such as plastics and paper
• Road chemicals such as salt from snow treatment and rubber from tires gripping the asphalt

Too much water, too fast: When stormwater falls on impervious surfaces, it cannot seep into the ground and runs off to lower areas. Consider a one inch of rain falling onto a meadow and a parking lot - the parking lot sheds 16 times the amount of water than the meadow does. When this extra water enters rivers, lakes and streams, it can erode the banks, cause local flooding, or washout wildlife and wildlife habitat.

Human component: Polluted stormwater runoff generally happens anywhere people use or alter the land. People going about their daily lives are the number one source of stormwater pollutants, yet most people are unaware of how their actions impact water quality. Some common examples include over-fertilizing lawns, excessive pesticide use, not picking up pet waste, using salt or fertilizer to de-ice driveways, letting oil drip out of their vehicles, and littering. In addition, various human activities like watering, car washing, and malfunctioning septic tanks can put water onto the land surface, which also runs off, taking pollutants with it into the waterways.

Developed areas, with their increased impervious surfaces and runoff, concentrated numbers of people and animals, construction and other activities, are a major contributor of nonpoint source pollution. Other human activities that contribute to polluted runoff include agriculture, forest harvesting activities, roadways, and malfunctioning septic systems.

Consequences of stormwater runoff: Polluted water creates numerous costs to the public and to wildlife. Here are just a few problems associated with stormwater runoff:

• Communities that use surface water for their drinking water supply must pay much more to clean up polluted water.
• Pathogens in the water can lead to beach closings and illnesses.
• Water running off of impervious surfaces is heated, which increases stream temperatures and kills fish.
• Dirt from erosion, also called sediment, covers up fish habitats, and fertilizers can cause too much algae to grow. Once the algae die, the dissolved oxygen in the water can be depleted by organisms decomposing the algae, resulting in harm to fish and wildlife.
• Soaps hurt fish gills and fish skin, and other chemicals damage plants and animals when they enter the water.
• Excess water contributes to and aggravates flooding problems.

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HOW DO YOU MANAGE STORMWATER RUNOFF?

Best management practices (BMPs) is a term used to describe different ways to keep pollutants out of runoff and to slow down high volumes of runoff. Preventing pollution from entering the water is much more affordable than cleaning up polluted water.

Some examples of stormwater BMPs are:

• Vegetative practices such as naturally vegetated filter strips along rivers, streams and lake banks, grassed swales, constructed wetlands, and tree plantings.
• Structural practices such as concrete grid and modular pavement; water diversion structures; extended water detention, retention and infiltration basins; porous pavement; green roofs; and water quality inlets (oil/grit separators).
• Maintenance practices such as limited application of fertilizers and pesticides; laws regulating litter, pet wastes, leaves, yard waste, and hazardous material disposal; regular vehicle and boat maintenance; street cleaning; and erosion controls from agricultural lands and construction sites.
• Education of local residents about how to prevent pollution from entering waterways in the first place.

The benefits of stormwater BMPs include:

• Flood prevention: Retention of runoff on-site, and its slow release prevents flood damage on-site and off-site.
• Groundwater recharge: Water that is absorbed into the ground recharges the water table.
• Erosion and sediment control: Reducing the volume of stormwater runoff from a site keeps the soil on the land and out of the storm drains, streets, and waterbodies.
• Improved water quality: BMPs that prevent polluted runoff from washing off the land and into rivers, lakes and stream protect our water for drinking, recreation, and wildlife habitat.
• Infrastructure protection: BMPs that help keep sediment out of highway ditches, culverts and waterways, reduce the costs for maintenance, dredging and replacement of these public facilities.
• Lower tax burden: When our water is polluted, we all pay in one way or another: damage from urban flooding can raise merchant prices and insurance rates; sediment and pollution laden water takes more money to treat before it can be used for drinking water; tourism and recreation businesses suffer along with residents when swimming, fishing and boating are curtailed; and the list goes on. The less polluted stormwater entering our waterways, the fewer tax dollars assessed for "clean up".

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WHAT CAN YOU DO TO REDUCE STORMWATER POLLUTION?

• Cars and boats
  • Maintain your vehicles so that they do not leak oil or other fluids.
  • Be sure to wash vehicles on the grass or at a designated car or boat wash so that dirt and soap do not flow into our storm drains and waterways; even biodegradable cleaning products can still be toxic to fish and stimulate algae growth.
     
• Yards and gardens
  • Apply only the recommended amount of fertilizer.
  • Never apply fertilizers or pesticides before a heavy rain.
  • If fertilizer falls onto driveways or sidewalks, sweep it up instead of hosing it away.
  • Mulch leaves and grass clippings and place in the yard at the curb - not in the street. This keeps leaves out of the gutter, where they can wash into the water or storm drain.
  • Turn your gutter downspouts away from hard surfaces.
  • Seed bare spots in your yard to avoid erosion.
  • Consider building a rain garden in low-lying areas of your lawn.
  • Use captured rainwater to water your garden.
     
• Septic systems
  • Proper maintenance includes having your septic system pumped every three (3) to five (5) years.
  • For older systems, make sure it can still handle current volumes.
  • Never put chemicals down your septic system. This can harm the system and seep into the groundwater.

• Pets
  • Clean up after your pet on walks and in your yard.
  • Dispose of all pet waste in the garbage.

• Chemicals
  • Keep lawn and household chemicals in tightly-sealed containers, where rain cannot reach them.
  • Dispose of old or unwanted chemicals at household hazardous waste collection sites or events.

• Other
  • Never put anything in a storm drain.
  • Don't litter.

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LINKS TO STORMWATER MANAGEMENTS PROJECTS IN OTHER COMMUNITIES

Michigan: Grayling Stormwater Project
Michigan: Greening Mid-Michigan Project
Chicago, IL: Green Alleys
Edmonton, AB: Treat it Right! Stormwater Education Program
Madison, WI: 1,000 Rain gardens
Portland, OR: A Sustainable Approach to Stormwater Management
San Francisco, CA: Stormwater Design Guidelines
Seattle, WA: Stormwater Management Program
Toronto, ON: Wet Weather Flow Master Plan

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REFERENCES

North Carolina Department of Environment and Natural Resources. Stormwater and runoff pollution: Pollute your water, pollute yourself, https://www.ncstormwater.org/pages/stormwater_faqspage.html (resource removed).

• alternative link: Erie County, New York, Department of Environment and Planning. How Can YOU Prevent Stormwater Pollution? https://www2.erie.gov/environment/index.php?q=how-can-you-prevent-stormwater-pollution

City of Redmond, Washington, Department of Public Works. Stormwater/drainage frequently asked questions. Stormwater Basics FAQs: https://www.redmond.gov/cms/One.aspx?portalId=169&pageId=179537 and Keeping Water Clean FAQs: https://www.redmond.gov/cms/One.aspx?portalId=169&pageId=179538.

• alternative link: City of Redmond, Washington, What is stormwater? FAQs: https://www.redmond.gov/faq.aspx?qid=196

Town of Yorktown, New York. Stormwater FAQs: https://www.yorktownny.org/engineeringandsewer/faqs-stormwater

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