Lane County Erosion Prevention Program Overview
In line with Lane County's commitment to creating a healthy and safe community, and to meet requirements of Lane County's Municipal Separate Storm Sewer System (MS4) General Permit and Willamette Basin Total Maximum Daily Load (TMDL) Implementation Plan, Lane County implemented an Erosion Prevention Program for the Lane County MS4 area outside the urban growth boundaries (UGBs) of Eugene and Springfield on May 1, 2024 (Lane Code 9.090 - 9.090.065).
Why is Erosion Prevention Needed?
The stormwater sewer system of Lane County is referred to as a “Separate Storm Sewer System”, a system that conveys stormwater directly to our local waterways often without passing through a treatment system. These systems are also referred to as MS4s or Municipal Separate Storm Sewer Systems. Any sediment, oil, or trash that enters a stormwater inlet has the potential to make its way to our local streams, rivers, and reservoirs unimpeded. For this reason, we must be mindful of stormwater pollution and how we can prevent it.
Runoff from construction activities can be a major source of stormwater pollution and lead to a cascade of negative effects for water quality and the people, animals, and plants that depend on our aquatic resources. Soils exposed during construction can carry sediment, trash, mercury, and other pollutants downstream during rain events. Increased sediment runoff can lead to harmful algal blooms, increase water temperature, deplete oxygen levels, and physically smother aquatic organisms and habitat. Oils, greases, concrete washwater, and other construction products can alter water chemistry, accumulate in the tissue of organisms, and lead to direct mortality of both aquatic and terrestrial organisms.
Why is an Erosion Prevention Program Being Implemented?
Due to the negative impacts that construction runoff can cause, the Environmental Protection Agency and Oregon Department of Environmental Quality have prioritized mitigation of construction site pollutant runoff, requiring MS4 operators to implement and enforce construction site runoff programs. These goals are further reiterated in Lane County’s Willamette Basin TMDL Implementation Plan where reduction of temperature, bacteria, and mercury loads are prioritized in an effort to preserve water quality throughout the Willamette Basin.
While only certain land-disturbing activities will need to obtain erosion prevention permits under this program, all land-disturbing activities that change the physical condition of a landform, its vegetation, and/or its hydrology, including but not limited to digging, clearing, grading, grubbing, excavating, filling, or storing materials must meet erosion prevention outcomes outlined in Lane Code 9.090.030:
- No construction-caused discharged to adjacent water features, natural resource areas, and other properties
- Protect and preserve riparian vegetation
- Keep both public and private stormwater systems, public rights-of-way, private roads, and natural resource areas free of sediment and construction-related materials
- Soils, stockpile areas, and debris piles may not be exposed to rain or stormwater runoff without approved BMPs
- Sediments that leave the property may not be more than that which would occur through natural processes on an undisturbed site
- The cleaning of equipment and vehicles may not discharge sediments and contaminants to public or private stormwater systems or to natural resource areas
- No hazardous substances may be released onto the site, adjacent properties, public or private stormwater systems, or natural resources areas
- Once construction is complete, the site must be stabilized so that long-term erosion and sedimentation does not occur
Where is the Erosion Prevention Program Being Implemented?
Lane County's Erosion Prevention Program applies to all new development, redevelopment, land-disturbing activities, and drainage projects that occur on property within the Lane County MS4 area surrounding the cities of Eugene and Springfield and outside UGBs of those cities. The cities of Eugene and Springfield implement their respective Erosion Prevention Programs within the UGBs of their cities per Lane Code 9.090.015. The area of implementation for Lane County's Erosion Prevention Program is indicated as "County-Administered MS4 Area" under the Erosion Prevention section of Lane County's Zone and Plan Map.
You can find more information about this program through the following resources:
Do I Need an Erosion Prevention Permit?