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Storm Water Management

Have you been told that you need a Stormwater Management Plan, or a Facility Operations and Maintenance Plan, or that you need to register the drywells on your property with the Oregon Department of Environmental Quality? We can help with that! Call us today at 503-233-8565.


In the Pacific Northwest, with average annual rainfall amounts routinely totaling 50 to 60 inches per year, typically occurring between the months of October and May, the implementation of stormwater best management practices is a key aspect for any development project.  Stormwater runoff is one of the largest sources of pollutants to waterways across the country.  Stormwater flows over impervious surfaces, as well as lawns and bare soils, and picks up and transports fertilizers, oil and grease, animal waste, and other pollutants. The Environmental Protection Agency has identified improperly managed stormwater runoff as one of the principle causes of water quality impairments and habitat degradation in developed and developing areas.  There is a growing public awareness of this issue nationally and in the Pacific Northwest.

  • To address post construction stormwater pollution, the Oregon Department of Environmental Quality’s 401 Water Quality Certification Program requires a post-construction stormwater management plan (SWMP) be submitted for review and approval by the agency. The plan must be submitted for all projects that require a federal permit or license and that results in an increase or redevelopment of impervious surfaces.  The SWMP applies to post construction permanent stormwater facilities such as constructed wetlands, bioswales, retention ponds, infiltration galleries and drywells.


  • Stormwater facilities that discharge stormwater runoff below the ground surface such as sumps, drywells, and soakage trenches are required to be registered as an Underground Injection Control (UIC) system with the Oregon Department of Environmental Quality.  UIC systems are regulated under the federal Safe Drinking Water Act (administered by DEQ) and the State Plumbing Code. DEQ regulates UICs under the Oregon Administrative Rules 340-40 and 340-44. UICs can pollute soil and groundwater if not properly designed, sited, and operated. In many cases, as site assessment is required to certify that the stormwater UIC system will not be exposed to contaminants.


AAI serves all of Oregon and Washington, including Portland, Salem, Gresham, Medford, Roseburg, Eugene, Corvallis, Bend, Klamath Falls, the Oregon Coast, the Columbia Gorge, Pendleton, La Grande, Vancouver, Olympia, Tacoma, Seattle, Spokane, and Tri Cities.

The experience of the Environmental Professional is the most important factor in insuring that your redevelopment project is conducted in accordance with the Oregon Department of Environmental Quality’s 401 Water Quality Certification Program. Our staff have extensive experience in stormwater management.