Concerned about growing nitrate contamination in Minnesota's drinking water, state regulators have ordered a farmer in the Pineland Sands area to complete a major environmental study before granting him a permit to dig an irrigation well.
The move could signal how state officials plan to respond to a decadeslong wave of deforestation in central Minnesota, where farmers and landowners have cleared thousands of acres of timberland to plant potatoes and row crops on land with vulnerable soil and groundwater.
An environmental study is essential because the state simply doesn't know the cumulative impact of irrigation and fertilizer use on water quality — and when it might reach a tipping point, said Randall Doneen, a conservation manager for the Minnesota Department of Natural Resources (DNR).
"There are a bunch of tiny straws right now on the camel's back, and it's not like we've determined that this will be the one that breaks it," Doneen said. "But at some point we will have crossed that threshold."

Last year, the DNR told cattle farmer Tim Nolte of Sebeka to complete a study known as an environmental assessment worksheet, which the agency will use to try to pinpoint what the impact his irrigation would have on the region. Nolte is seeking three permits to irrigate a total of about 300 acres in Wadena County.
While those 300 acres are just a sliver of the timberland that has been converted to row crops in central Minnesota, the DNR must determine if the watershed can handle more irrigation and fertilizer and where to draw the line, Doneen said.
The DNR's move has caught the attention of lawmakers in both parties. Nolte was asked to speak before a legislative subcommittee in December, where he said he felt he was caught in the middle of larger battle that had little to do with him or his farming practices.
"We got caught in [the] cross hairs of people to the north of us 40 to 50 miles," Nolte told lawmakers.