By Patrick Lynn
The first-ever Tomorrow River status report was released Friday.
The 36-page 2019 State of the River report examines water quality and provides a benchmark for future land management decisions, and was compiled by College of Natural Resources specialists at the University of Wisconsin-Stevens Point.
The Tomorrow River watershed includes 120,000 acres in Portage County, of which 30 percent is in agricultural lands. The report details the watershed’s land management practices, groundwater and surface water quantity, and streamflow concerns, water quality issues, including nitrates and water temperatures and fishery status.
The report highlights the challenges of making water quality improvements in the river, which was listed by the state in 1993 as a priority watershed project. The report details some of the “numerous management practices to reduce environmental impact” voluntarily installed since then by Portage County staff and landowners.
But water quality improvements in some areas may be offset by changes in others, the report said. Little change in nitrate concentrations in the Tomorrow River was found over time, with approximately 16 percent of sampled residential wells exceeded the safety standard for nitrate in drinking water.
Phosphorus, which causes algae growth and diminishes water quality, was high in two tributaries and three lakes of the Tomorrow River watershed. The report notes that these observations are based on limited monitoring data.
Water quantity and stream temperature are also explored in the report. The report cites a recent study of groundwater in the watershed showing streamflow in the Tomorrow River is reduced by pumping from high capacity wells. A summary of temperature data gathered between 1998 and 2016 showed warming temperatures limited brook trout. Temperatures below the dam in Amherst were too warm for brook trout in the summer.
The report was funded by the George Rogers Memorial Tomorrow River Fund, the Wisconsin Department of Natural Resources (DNR) through a grant to Portage County, the Bill Cook Chapter of the Izaak Walton League and Tom and Nancy Miller of Waupaca.
The Tomorrow River flows through Portage and Waupaca counties and is recognized statewide for supporting native trout, wildlife, recreation, and economic development. Groundwater is the primary source of water to the Tomorrow River and results in a fishery that is home to 26 species including native brook trout, brown trout, bluegill, walleye, northern pike and others. Streamflow, water quality, water temperatures and healthy tributaries all affect the fishery.
The 2019 State of the River report is on the Portage County website: www.co.portage.wi.us.