Column: Little Plover River is in trouble

By Bill Davis and George Kraft

Once again, the Little Plover River is in trouble, and not only because of this summer’s drought.

To understand why the Little Plover isn’t flowing like it has been in the past few years, we have to look underground.

In 2013, the Little Plover River was named one of the United States’ most endangered rivers by the American Rivers water advocacy group. The river dried in stretches every year from 2005 through 2010, and otherwise often flowed below “healthy” flows.

“Healthy” flows, or “public rights flows,” are based on the minimum needed to keep fish habitat below the water surface. They were set by the Wisconsin Department of Natural Resources shortly after Little Plover stretches dried for the first time in 2005. The healthy flow is at least four cubic feet (30 gallons) per second, or 4 cfs at the USGS gauge at County Rd R. Recent flows have been about 40-50 percent less than the healthy minimum.

August 24 marked two months that Little Plover River flows were less than “healthy.” While the last decade of record precipitation helped the aquifer and river temporarily recover, this year’s high capacity well pumping is spiking irrigation demand and depleting Little Plover flows. Flows dropped to less than healthy levels on June 24 and have remained there almost continuously. Flows dropped rapidly from a healthy 10 cfs in early May to only 2 cfs in late July, a decline of over 80 percent in less than three months.

“Without high capacity well pumping the Little Plover would be doing well right now,” said George Kraft, Professor Emeritus of Water Resources with UW-Stevens Point and Extension. “The notion that drought alone is stressing the Little Plover is just plain wrong. The past decade has been about the wettest in local history, and even in 2023 rainfall was above average through June. Nearby groundwater-fed streams where there is little groundwater pumping are well within a ‘healthy range,’” he said.

Groundwater-fed streams, Kraft explained, have the equivalent of “money in the bank” for dry times due to water stored in aquifers during wet times. Groundwater discharging to such streams can normally maintain healthy flows during dry times. But when dozens of neighboring high capacity wells pump groundwater, both the aquifer and stream run low on water, just like running up credit card charges causes real “money in the bank” to run low. This demonstrates the fact that precipitation, while important, does not solely determine healthy flows in streams, particularly in the Central Sands.

Efforts for a permanent solution to over-pumping included 14 years of talks between conservationists and groundwater pumping interests – irrigated producers, the Village of Plover, and industry – but yielded little result. Pumpers began a closed process of “Little Plover Enhancement” in 2018 with a commitment to restoring Little Plover healthy flows.

“Enhancement has been a mixed bag,” said Kraft. “It’s done some nice stuff like habitat improvement, creating a wetland, killing invasive buckthorn, and making promotional videos. But as far as putting flow back in the river, it appears like thimblefuls at great public cost. The late Barb Gifford, a Little Plover champion, calculated once that over $2 million of public dollars have been spent with only a small effect.”

This situation highlights the need in Wisconsin for a comprehensive, integrated and enforceable system of managing our shared waters for the long-term benefit of everyone.

Bill Davis is a senior legal analyst for the River Alliance of Wisconsin
George Kraft is a Professor Emeritus of Water Resources with UW-Stevens Point and Extension