In nature, precipitation falls onto forests, grasslands, and other natural areas where the excess water can soak down into the soil, through the water table, and eventually out into water bodies. In cities, this water cycle is broken by pavement, rooftops, and other structures.
During the construction of roads, buildings, and other structures, the natural infiltration of stormwater runoff is interrupted, resulting in increased rates of runoff and flooding. The increased impervious surface area adds pollutants to streams, rivers, and other water bodies.
Soil is the most critical resource in stormwater management as it is a living, breathing, dynamic system that can treat stormwater via filtration into the ground. The physical, biological, and chemical structure of soil is also an important aspect of managing stormwater runoff. When soil is disturbed from grading, tilling, etc., the structure that holds sand and clay together is broken.
Highway Fuel is the Willamette Valley’s premier source for Water Quality Mix Soil (also know as Bioretention, Biofiltration, Bio-soil, Amended Soil Growing Media, Planting Media, Stormwater Soil, Engineered Soil) for your project’s stormwater low-impact developments, such as bioswales, detention ponds, and filter strips, that are required to have specific soil blends. We offer a variety of pre-spec’d Water Quality Soils, including soils designed and verified to meet the specifications of the following municipalities/agencies:
- Oregon Department of Transportation (ODOT)
- Washington Department of Transportation (WDOT)
- City of Portland, Bureau of Environmental Services (BES)
- City of Keizer
- City of Salem
- City of Albany
- Washington County
Our on-site soil specialist can also create a custom soil to fit your project’s specific needs.
Water Quality Soil Mixes are blends of sand, topsoil, and compost. These mixes must be balanced in a way that can sustain plant growth, provide treatment, and infiltrate quickly.
A WQM that meets the City of Portland’s Standard Construction Specifications (SCS) for Stormwater Facility Blended Soil for use in vegetated stormwater systems such as swales, planters, curb extensions, and basins.
Ecology mix is used in the creation of Bio-slopes, flow-through stormwater treatment facilities incorporated into roadside embankments. Bio-slopes are recommended for highway application because of their minimal right-of-way and maintenance requirements
In the past, Stormwater soil mixes have primarily used sand as the predominant soil type as this results in high infiltration rates. This approach does not always provide the results required for certain projects, as the suitable soil for stormwater BMPs will vary by type and location. Every stormwater project has different functional and environmental needs requiring the appropriate soil. Because of this, the design guidance for stormwater best management practices (BMPs) is constantly changing to allow for more regional policies. Some regions minimize fines in stormwater soil based on their potential to clog infiltration filters. Other regions are realizing that silts and clays help stabilize plant growth and help maintain consistent infiltration rates of stormwater BMPs for extended periods.