Stormwater Runoff
What is Stormwater Runoff?
After a rain event, water that falls on natural surfaces infiltrates the ground and eventually into the groundwater.
Water that falls on impervious surfaces, such as roads, rooftops, and other paved surfaces, cannot soak into the ground. Instead, it flows over surfaces, picking up pollutants, such as oils, salts, debris, sediments carrying phosphorus, and other chemicals and depositing them into the lake.
Stormwater runoff isn’t just a problem along roads and commercial areas. Residential properties generate runoff as well.
Stormwater runoff from developed areas poses a significant threat to the water quality of Twin Lakes.
Relationship between impervious cover and surface runoff. Impervious cover in a watershed results in increased surface runoff. As little as 10 percent impervious cover in a watershed can result in stream degradation.
In Stream Corridor Restoration: Principles, Processes, and Practices (10/98). By the Federal Interagency Restoration Working Group (FISRWG) (15 Federal agencies of the U.S.)
What Are the Effects of Stormwater Runoff?
A decline in water quality and clarity from pollutants and sediment.
Impeded navigation due to sediment.
Increased weed and algal growth due to excess nutrients.
Unsafe water for swimming due to bacteria and pathogens.
Harm to aquatic life from debris, as well as hazardous materials (pesticides, paints, motor oil, etc.).
Erosion of stream banks and loss of habitat.
All of the above lead to a loss in water quality, damaging the economy and impacting, property values, and quality of life.
Contribution from Byron Nickerson, Twin Lakes Resident *
Stormwater Management During your Construction Project
Importance of Controlling Construction Stormwater Discharges
When it rains, stormwater washes over the loose soil on a construction site, along with various materials and products stored outside. As stormwater flows over the site, it can pick up pollutants like sediment, debris, and chemicals from that loose soil and transport them to nearby storm sewer systems or directly into rivers, lakes, or coastal waters. Construction site operators must have the proper stormwater controls in place so that construction can proceed in a way that protects our community’s clean water and the surrounding environment.
Pollutants commonly associated with construction sites:
EPA
Sediment
Solid and sanitary wastes
Phosphorus
Nitrogen
Pesticides
Oil and grease
Concrete truck washout
Construction chemicals
Construction debris
Leaves and other organic matter
Common Best Management Practices (BMP’s) for contractors is to:
1. Limit land disturbance
2. Preserve the natural vegetation
3. Use man-made erosion controls
4. Capture sediment laden water
5. Properly store and cover worksite materials
6. Conduct frequent inspections
7. Stabilize the work zone after construction has ceased
If you are not seeing these BMP’s, or have not discussed these with your contractor, would you like someone to (confidentially) help you and your contractor implement and maintain simple, but effective stormwater control measures before, during and after construction? If so, send your request and contact information via email to info@stewardsoftwinlakes.org.
For more information on residential stormwater management see:
· EPA Stormwater Pollution Prevention for Residential Construction Sites
* Contributor Byron Nickerson is an accomplished environmental consultant with a robust background in water quality and watershed management. With a Master’s Degree in Geologic Oceanography and a Bachelor’s in Geology, he brings a wealth of expertise to our Twin Lakes community . Early in his career, Byron conducted multi-disciplinary coastal oceanographic surveys, focusing on vital factors such as circulation, pipeline routes, and channel dredging. As a consultant, Byron has managed a variety of projects that emphasize regulatory compliance, hazardous waste site investigations, remediation efforts, health and safety, and disaster response. Byron’s commitment to helping maintain our Twin Lakes watershed health and working with property owners and their Twin Lakes home construction site with runoff issues will be invaluable.