Of all of the watersheds in the Red River Basin, the Otter Tail River watershed is one of the least impacted by flooding. Annual average flood damage in the watershed is estimated at $457,784 (in 1996 dollars) with 99% of the damage being rural.
The main resource concerns in the watershed are wind and water soil erosion, wetland management, surface water quality, stormwater runoff, and wildlife habitat. Many of the resource concerns relate directly to changing land use and increased development in the region, resulting in fragmentation and increased sediment/pollutant (mercury, excess nutrients) loadings to surface waters. A significant portion of the land within this watershed is considered highly erodible, or potentially highly erodible. Land use within the watershed is largely agricultural, accounting for approximately 45% of the overall watershed acres. Development pressure is moderate to considerable in some areas, with occasional farms, timberland, and lakeshore being parceled out for recreation, lake, or country homes.
What's being done
Monitoring and assessment
Intensive watershed water quality monitoring was conducted in 2016. A monitoring and assessment report was drafted in 2018. A Stressor Identification Report was completed in 2019. Realtime flow monitoring was installed at three locations in the watershed. Those flows can be found on the MPCA/DNR cooperative stream gaging web page.
Strategy development for restoration and protection
A Watershed Restoration and Protection Strategies (WRAPS) project started in 2019. A WRAPS Report and a Total Maximum Daily Load (TMDL) Report are currently being developed, with an expected public notice and completion by the end of 2020 or early 2021.
A Lower Otter Tail River Restoration federal 319 grant project was completed in the fall of 2019. This projected included surveying, planning and designing channel restorations for approximately 20 river miles channelized in the 1950s as part of a flood reduction project. The project area is located between Orwell Dam and Breckenridge Lake. The idea is to improve water quality by reducing sediment associated with stream bank failure, erosion, and channelization. This project provides the design work for future restoration projects that will aim to address the excess sediments and retain the river’s flood damage reduction features.
In June 2016 a group of 20 resource managers, local decision makers and land owners formed a civic engagement cohort, led by staff from the U of M Extension Service. Members learned about skills training, leadership training and watershed science. They met monthly and completed formalized training in May 2017. Members facilitated discussion and decision-making regarding water quality issues in the watershed.
The St. Clair Lake TMDL Report was completed in 2016. The Pelican River Watershed District sponsored and managed the TMDL study and provided funding. In addition, the city of Detroit Lakes partnered with the MPCA and watershed district on the report. The purpose of the St. Clair Lake TMDL Report is to address the excess nutrients, particularly phosphorus, in the lake, and to provide pollutant reductions that will be needed to help restore the lake and to protect downstream waters from further pollution.