Services
BMP
Stormwater Best Management Practices (BMPs) include a variety of techniques implemented to minimize erosion, control sediment, and prevent other pollutants from leaving the construction site in stormwater runoff and snowmelt. Since disturbed soil is highly susceptible to erosion, these BMPs focus on either preventing soil from being carried away by water (erosion control) or capturing sediment once it has eroded (sediment control). Common examples include silt fences and straw wattles installed along the downslope perimeter to slow down and filter runoff, stabilized construction entrances to reduce tracking mud and dirt onto public roads, and storm drain inlet protection to keep debris out of the storm drains and waterways.
What are BMPs?
BMPs stand for Best Management Practices. They're the different techniques, activities, and products you use to minimize stormwater pollution from leaving your site. They're the physical practices you implement to prevent dirt, chemicals, and other pollutants from entering the storm drains and eventually, our waterways.
Why are BMPs Important?
Water Clarity: Sediment from runoff clouds waterways, reducing sunlight penetration needed for aquatic vegetation to thrive and impacting visual predators.
Habitat Degradation: Sediment runoff can suffocate fish eggs and larvae of insects, fill the gills of fish, and blanket benthic organisms. Sediment can damage stream channels and wetlands, decreasing their volume and changing flow regimes.
Infrastructure Damage: Storm drains, culverts, and other infrastructure clogged by sediment can cause flooding and higher maintenance expenses.
Carrying Other Pollutants: Sediment particles can carry other pollutants such as nutrients, heavy metals, and pesticides and carry them into water bodies.
Regulatory Compliance: Installing and maintaining BMPs is required in order to stay compliant with the EPA, State, and local environmental regulations.
Avoidance of Penalties and Fines: Well-managed sites have less risk of regulator enforcement and penalties.
How Do We Determine Which BMPs to Implement?
The specific BMPs we recommend depend on several factors, including:
The nature of the construction work
The size and topography of your site
The kind of soil available
The closeness to susceptible water bodies
The overall weather patterns
Specific EPA, State and Local requirements
We thoroughly examine your construction site, civil plans, and mapping programs to select the most effective and affordable BMPs for your specific requirements.
What are Some Common BMPs
Silt Fences: Temporary fabric barriers that are similar to low fences and are designed to catch sediment (dirt) carried by runoff, especially on slopes and around the edge of disturbed areas.
Straw Wattles (or Fiber Rolls): These are tubular devices constructed from straw or other natural fibers. They're laid across slopes to retard water flow and filter out sediment. Think of them as speed bumps for muddy water.
Stabilized Construction Entrance (Trackout Controls): This is the controlled vehicle entrance and exit area. They are typically constructed out of aggregate, metal, or plastic pads. Trackout controls assist in removing mud and dirt from tires prior to exiting the site and transferring it onto public roadways.
Storm Drain Inlet Protection: There are several "traps" or "filters" in and around storm drain inlets (such as "witches hats," gravel bags, or grate covers) available to block sediment and debris from entering the drainage system.
Concrete Washout: These are contained areas or portable containers where concrete truck chutes can be washed out without the acidic fluid polluting the groundwater and waterways.
Proper Disposal of Waste: This includes preventing trash bins from being overfull and not allowing any of the construction waste or litter to be carried or blown away.
Covering Stockpiles: Construction materials that have been chemically treated or can rust must be covered.
Proper Placement of Portable Toilets: To prevent portable toilets from being blown or pushed over and spilling into a storm drain or waterway, they must be moved 10’ back from any conveyance and staked down. If that is not possible, the toilet needs to be placed in a secondary containment and tied down.
Soil Stabilization: Vegetation cover (perennial or temporary seeding), mulch, or erosion control blankets over exposed soil shields the soil from wind and water erosion.
Dust Control: Dust control is extremely significant in dry climates. Remedies can include watering the site, using dust suppressants, and covering stockpiles of soil.
How often do BMPs need to be checked and maintained?
Inspection Intervals: Regular inspection and maintenance are crucial for BMP effectiveness. Generally, BMPs are required to be inspected for damage or lack of function:
Either every 7 days or 14 days per permit requirements. In some arid climates, monthly is allowed.
After a rain event of .025 - .50 inches.
When soil or pollutants are observed leaving the site.
Maintenance Steps: Maintenance includes things like removing accumulated sediment against silt fences, cleaning filled inlet protections, repairing damaged BMPs, refreshing trackout controls, and ensuring each control is functioning properly.
What happens if BMPs aren't maintained?
If a BMP lacks maintenance, it won't effectively prevent stormwater pollution. This can lead to:
Non-compliance with your SWPPP and permits.
Potential fines and enforcement actions.
Environmental damage.
Accena SWPPP Services helps you understand the maintenance requirements for your chosen BMPs, provide required inspection services to verify they are working correctly, and can even install and maintain them.