As climate change continues to impact weather patterns and intensify storm events, it’s more important than ever to prioritize effective stormwater management practices. Stormwater runoff can cause significant environmental damage, including erosion, water pollution, and flooding. That’s why implementing Best Management Practices (BMPs) for stormwater management is critical for property owners, managers, and environmental professionals alike. In this informative article, VERTEX’s team of experts provides insights into the most effective BMPs and how to implement them to reduce the impact of stormwater runoff. Let’s dive in and explore the best stormwater management practices that can help protect our environment and communities.
What is Stormwater Runoff and its Impact?
According to the Massachusetts Department of Environmental Protection (MADEP), stormwater runoff results from rainfall and snow melt and represents the single largest source responsible for water quality impairments in rivers, lakes, ponds, and marine waters. The best way to control stormwater runoff on your site is to implement best management practices (BMPs).
What is a Stormwater Best Management Practice?
Per the United States Environmental Protection Agency (EPA), Stormwater Best Management Practices are schedules of activities, practices (and prohibitions of practices), structures, vegetation, maintenance procedures, and other management practices to prevent or reduce the discharge of pollutants to waters of the United States. BMPs also include treatment requirements, operating procedures, and practices to control plant site runoff, spillage or leaks, sludge or waste disposal, or drainage from raw material storage.
Types of BMPs
Most states and municipalities divide Best Management Practices into two (2) categories: Structural or Non-Structural. Structural BMPs are engineered systems or techniques for managing stormwater to reduce and mitigate impacts of development. Non-Structural BMPs are design approaches and practices used to prevent the occurrence of stormwater runoff.[1]
Non-Structural BMPs[2]
- Street Sweeping
- Catch Basin Maintenance
- Road Salt Management
- Spill Prevention and Control Plans
- Integrated Pest Management
- Snow Disposal
Structural BMPs
Bioretention Areas
“Bioretention is a technique that uses soils, plants, and microbes to treat stormwater before it is infiltrated and/or discharged.”
Figure 1: Bioretention area at Cunniff Elementary School in Watertown, MA
Constructed Stormwater Wetlands
“Constructed stormwater wetlands are stormwater wetland systems that maximize the removal of pollutants from stormwater runoff through wetland vegetation uptake, retention and settling.” – MA Stormwater Handbook Volume 2 Chapter 2
Figure 2: Constructed Stormwater Wetland at Kennedy Middle School in Natick, MA
Dry Wells
“Small, excavated pits. Backfilled with aggregate and used to infiltrate uncontaminated runoff from non-metal roofs or metal roofs located outside the Zone II or Interim Wellhead Protection Area of a public water supply and outside an industrial site.” – MA Stormwater Handbook Volume 2, Chapter 2
Image Source: Structural BMPs – Volume 2 | Chapter 2 page 85
Pervious Pavement
Figure 3: Pervious Pavement at Cunniff Elementary School in Watertown, MA
Subsurface Infiltration
“Underground systems that capture runoff, and gradually infiltrate it into the groundwater through rock and gravel.” – MA Stormwater Handbook Volume 2, Chapter 2
Figure 4: Example of an underground infiltration system [3]
Proprietary Separators
“A proprietary separator is a flow-through structure with a settling or separation unit to remove sediments and other pollutants.” [4]
Sand & Media Filters
“Also known as filtration basins, sand and organic filters consist of self-contained beds of sand or peat (or combinations of these and other materials) either underlaid with perforated underdrains or designed with cells and baffles with inlets/outlets.” – MA Stormwater Handbook Volume 2, Chapter 2
Deep Sump Catch Basins
“Deep sump catch basins, also known as oil and grease or hooded catch basins, are underground retention systems designed to remove trash, debris, and coarse sediment from stormwater runoff, and serve as temporary spill containment devices for floatables such as oils and greases.”[5]
Considerations When Selecting BMPs
When selected which BMPs are best for your project, you should consider the following factors: Site conditions (i.e. soil types, topography, etc.), existing and surrounding land uses, local and state stormwater regulations, and the projects site development/redevelopment goals (i.e. LEED certifications, recreational uses, etc.). Non-structural BMPs tend to be more cost effective, however structural BMPs may help you reach your stormwater management goals more effectively.
To learn more about VERTEX’s Civil Engineering Design services or to speak with an Engineering Expert, call 888.298.5162 or submit an inquiry.
Resources:
[1] https://spcwater.org/topics/stormwater-management/stormwater-best-management-practices-2/
[2] https://megamanual.geosyntec.com/npsmanual/sectionintrourbanstormwaterrunoff.aspx
[3] https://cultec.com/stormwater-systems/
[4] https://megamanual.geosyntec.com/npsmanual/proprietaryseparators.aspx
[5] https://megamanual.geosyntec.com/npsmanual/deepsumpcatchbasin.aspx