The Chippewa County Board received the results of a multiyear study of the county’s groundwater Tuesday which confirmed that groundwater can be affected by mining and agriculture, while offering ideas to mitigate effects.
The board also passed a resolution updating their water management plan.
The study, done by the Wisconsin Geological and Natural History Survey and the United States Geological Survey, ran from 2012 to 2017 and was implemented to help the county better understand how to move forward with water management.
The study cost around $625,000 and was paid for through grants, non-metallic mine reclamation program fees and other non-government funds.
Primarily, they found that while mining and agricultural uses could have effects on groundwater, those can be somewhat mitigated through planning and management.
Those effects can include decreased infiltration of water into the ground and depleted groundwater reservoirs.
Dan Masterpole, deputy director of the county’s Land Conservation and Forest Management Department, said a primary concern driving the study was the advent of both serious industrial sand mining in the area and irrigated agriculture.
Masterpole said the groups were able to harness information from many stakeholders, including people in the mining and agriculture industries, to learn about the geology, water use and land management in the areas.
“It was a very collaborative effort,” Masterpole said.
Key conclusions to the study include that headwater streams are most sensitive to groundwater withdrawals and changes from sand mining and irrigation.
It also noted that impacts from industrial and agriculture could be increased due to natural variables like droughts.
In their simulated tests and modeling, researchers concluded that both mining and irrigated farming could have effects on the groundwater and stream levels, the effects of irrigated agriculture had less of a chance of being mitigated later by reuse or reclamation.
Michael Parsen of the Wisconsin Geological and Natural History Survey, noted that the purpose of the study was to give the board tools to make informed decisions with those land uses moving forward.
“While there are impacts that we modeled ... there are also ways and steps that decision makers could make to mitigate those impacts,” Parsen said.
Some ideas included in the study to help prevent effects of groundwater withdrawal include pumping as far away as possible from sensitive streams, staggering mine development over time, and reclaiming mined areas with land cover that is easily infiltrated by water.
The updated water management plan was passed in a 10 to three vote, with supervisors Steve Gerrish and Kari Ives absent.
The purpose of the update — which they do every five years — is to report the county’s progress, show accountability, establish a new schedule of activities and performance benchmarks, and update the county’s strategy to implement performance standards for nonpoint source runoff pollution control at farms.
The county is required by state statute to have a land and water resource management plan to identify issues of environmental concern, establish resource management objectives, and coordinate resource management programs administered by federal, state, and county agencies.