Total Maximum Daily Load (TMDL)

The City of McMinnville is an attractive, vibrant community with a vigorous and walkable downtown area. The City has approximately 350 acres of parks including 70 acres of undeveloped natural areas with multiple nature trails - two of those directly adjacent to the South Yamhill River.

McMinnville does not currently have a stormwater, environmental division, or fee structure for dedicated funding. For the most part, stormwater activities such as street sweeping, catch basin cleaning, storm line repair, and detention basin maintenance are performed by our Wastewater Conveyance group and Street Maintenance staff.

Addressing the goals for the Total Maximum Daily Load aligns with the City's commitment to being proactive in maintaining a community where people want to visit, live, and recreate. 

What is a Total Maximum Daily Load?

A Total Maximum Daily Load (TMDL) refers to identifying the source(s) of mercury in our waterways and determining how much mercury should be reduced to meet state and federal water quality standards. 

The ultimate goal of this process is to provide full restoration of the beneficial use of fish consumption, including the protection of aquatic species and wildlife throughout the Willamette Basin.

On March 3, 2021 the City of McMinnville was notified of its status as a Designated Management Agency (DMA) to the Willamette Basin. To be a "DMA" means that a federal, state or local governmental agency that has legal authority over a sector or source contributing pollutants, and is identified as such by the Department of Environmental Quality. DMAs are responsible for implementing strategies and specific plans for addressing Total Maximum Daily Loads (OAR 340-042-0030(2)).

According to the Department of Environmental Quality (DEQ), the approach of this TMDL plan are consistent with the requirements of the federal Clean Water Act (CWA) and Oregon water quality laws and implementing regulations. 

Despite the lack of an established stormwater program, the City shows a strong dedication to participating in environmental activities. Staff actively engages with the Greater Yamhill Watershed Council, supports the Friends of Cozine Creek community group, and utilizes an Integrated Pest Management Plan (IPM) in our parks and open spaces. Engineering and Wastewater staff have been innovative with the use of green elements at the Water Reclamation Facility. These activities will continue to serve McMinnville as the community takes on the responsibility of implementing a TMDL Plan.

Summary of TMDL Plan Development

The City of McMinnville has developed an implementation plan that meets the requirements
listed in the Water Quality Management Plan (WQMP),  and is consistent with the timelines listed in Table 13-14 in the attached document. 

In November 2021, the City hired a consultant which spent two days with key staff to provide background and instruction on TMDL implementation and how it applies within our region.

Initial steps for plan development focused on the formation of the best management practices to be used by the City as a new TMDL agency. More importantly, the City has been focused on the control measures and their role in pollutant reduction. Emphasis has been placed on educational activities and
training to allow time for staff to review the existing water quality-based actions and expand on them. 

The City's TMDL Plan, as approved by City Council, is attached below.

DEQ is interested in supporting public involvement in these activities. If you have questions or comments please reach out to Logan Adams. Please include your name, email address, and phone number in your correspondence.