Construction Sites, Home Repairs & General Contractors

Stormwater Pollution

Stormwater is rain or snowmelt that flows over the ground. As stormwater runs over impervious surfaces like driveways, roofs, sidewalks, and streets; it can pick up pollutants that have collected on these surfaces – such as motor oil, fertilizers, pesticides, and trash – and allow them to flow into stormwater catch basins. Stormwater flows into the storm drain system and is discharged without treatment into local waterways.

Poor training and material management practices at locations under repair or construction can cause pollutants such as trash, debris, sediment, oil, solvents, and paint waste to enter our stormwater system. These pollutants can build up in stormwater lines and cause blockages, negatively impact the operation of stormwater retention areas and drywells, or degrade the water quality of our washes and rivers. Pathways of this pollution include the direct pouring or dumping by ill-trained employees, poor cleaning habits, improper storage of chemicals and waste, and poor maintenance of waste containers.

Recommended Practices for Construction Sites, Home Repairs & General Contractors

Many of the Best Management Practices (BMPs) identified below are non-structural and cost little or nothing to implement. This listing is not all-inclusive and other non-structural and structural BMPs can be implemented to further reduce the potential of contributing to stormwater pollution.

Waste & Materials Management


  • Contain all demolition materials and waste construction and packing materials in covered trash dumpsters or roll-off bins.
  • Cover landscaping materials, such as crushed gravel or stone, or excavated soils. Store these materials on bare soil or plastic sheeting instead of pavement and in areas not susceptible to stormwater runoff.
  • Store building materials (roof rafters, framing boards, concrete bags, etc.) elevated above-ground surface and in areas storm water does not flow or accumulate.
  • Set up controlled concrete truck washout areas, frequently dispose of this material, and keep these areas clean.
  • Keep solvents, paint cans, and bulk paint supplies sealed and store them in areas protected by secondary containment.
  • Daily sweep or vacuum sawdust and dirt inside building structures without completed walls and roofs.
  • Use brooms, blowers, or street-sweeping machines to clean outdoor areas.


  • Leave waste materials lying on the ground or street and allow these materials to blow or wash into the stormwater system.
  • Pile landscape materials, such as crushed gravel or stone, or excavated soils directly on paved surfaces, or leave these materials uncovered and blow/wash into the stormwater system.  
  • Place building materials (roof rafters, framing boards, concrete bags, etc.) directly on bare soil or paved areas or in areas where stormwater may accumulate or flow.
  • Establish concrete truck washout areas in areas where stormwater will flow, not maintain these areas, or allow these areas to overflow.
  • Allow storage of open containers of paints or solvents or any conditions that may allow these chemicals to enter the stormwater system.
  • Allow sawdust and dirt to be blown or washed into the stormwater system from the interior of incomplete building units.
  • Clean outdoor paved surfaces using a pressure sprayer, a hose, and / or detergents.



  • Have designated parking areas for all equipment and personal vehicles.
  • Place berms around vehicle parking areas and drip pans or plastic sheeting beneath equipment stored onsite to contain fluid leaks.
  • Clean up oil leaks and fluid spills promptly using dry adsorbent materials.
  • Keep absorbent cleanup materials readily accessible in all work areas.
  • Properly contain and dispose of used absorbent materials as required.


  • Have equipment and vehicles stored and parked throughout the site.
  • Allow leaky vehicles and equipment to be discharged from vehicle parking areas and flow into the stormwater system.
  • Allow spilled materials to be tracked out of or throughout the site.
  • Waste time responding to a spill or leak by looking for the appropriate cleanup materials.
  • Pile spent absorbent materials on the ground or dispose of them uncontained in a dumpster.

Sediment Control


  • Install controls to keep sediment from being tracked out onto street surfaces. Maintain these structures frequently, especially after rainfalls.
  • Hire a street sweeping company to frequently wash interior project paved areas and affected arterial streets.
  • Preserve natural site conditions such as trees, scrubs, and grasses as long and as much as possible.
  • Install and maintain brush barriers/waddles, silt fences, check dams, catch basin sediment filters, traps or basins, etc.
  • Install riprap in areas where stormwater is channeled or discharged from pipes.
  • Install geotextile fabric, waddles, or other stabilizing devices on sloped areas and install surface landscape as soon as possible.
  • Control dust with silt fences and other wind-breaking devices. Use only what is required to do the job when using water trucks for dust control.


  • Allow track-out control structures to become laden with sediment and allow sediment to be tracked onto the street or into the stormwater system.
  • Spray down streets with a hose or use a pressure washer to clean interior project paved areas or arterial streets.
  • Do mass grading and remove all-natural ground-covering plants until other soil stabilization techniques are utilized.
  • Allow sediment to impact existing stormwater structures or to cause erosion within or around those that are currently under construction.
  • Leave areas where stormwater is channeled or discharged unprotected from erosion.
  • Allow the banks of an excavation or retention basin to fail by not installing slope stabilizing devices.
  • Allow sediment to be blown into the air or over-apply water during dust control activities and therefore be discharged to the stormwater system.

Staff Training


  • Train employees and proper materials management, storage, disposal, and spill cleanup procedures.
  • Post a listing of Best Management Practices where all employees will have reference to it.


  • Assume your staff knows or will implement the proper materials management, storage, disposal, and spill cleanup procedures.
  • Expect your employees to remember the proper ways of cleaning and handling waste.


  • It is easier and cheaper to prevent stormwater pollution than to clean it up.
  • Your facility is not “safe” from stormwater pollution regulations.
  • Developing, implementing, and maintaining a Stormwater Pollution Prevention Plan (SWPPP) onsite, even if your operations are not required to do so, would help keep your operations from negatively impacting the stormwater system.