Groundwater levels a rising concern in Minnesota
Editor’s note: This is the second part of a two-part story examining Perham’s water. This article focuses on groundwater levels, while the first part, published in last week’s Focus, looked at nitrate levels in the drinking water.
Groundwater has been making waves in Minnesota lately, with lawmakers, the media and the public all showing an increasing awareness of sustainability issues around different parts of the state.
In Hibbing, for example, one of the city’s three wells has dried up. And the level of White Bear Lake is noticeably dropping.
In late February, the Star Tribune reported that many regions in the state have reached a point where people are using water faster than the rain and snow can replenish it. The article, written by Josephine Marcotty, states that Minnesotans used a record amount of water last year, and now state regulators are, for the first time ever, considering saying “no” to water permits in problem areas.
Results of a Freshwater Society study, released in April, show that reported groundwater pumping increased by 2.8 billion gallons per year in Minnesota from 1988 through 2011 – a 31 percent increase. By comparison, the state’s population increased 24 percent in that same period. Agricultural irrigation, the second-biggest use of groundwater and the fastest-growing by far, increased about 73 percent during those years. Pumping by city water systems, the biggest single use, increased 33 percent statewide.
The Department of Natural Resources, U.S. Geological Survey and Metropolitan Council’s top water planner warn that current pumping levels are unsustainable, or close to becoming unsustainable, in some areas of the state – notably, around the heavily populated and fast-growing Twin Cities metro.
The Perham area, and Otter Tail County as a whole, are of lesser immediate concern, with no evident long-term signs of overuse.
Data from the Minnesota DNR’s website shows that water levels around the Perham area have remained relatively stable since they first started being monitored in 1967. Unusually dry or wet years have created temporary spikes or drops, but overall the levels haven’t changed much. And for this spring, they’re looking pretty good.
“Generally speaking, after this fall and winter and spring recharge, our groundwater levels appear to be normal,” said Julie Aadland, a Fergus Falls-based hydrologist for the Minnesota DNR’s Northwest region. “I don’t think we necessarily have a concern about low groundwater levels at this point, in this part of the state.”
Yet, with ever-increasing domestic and agricultural groundwater usage, she hesitated to use the word “sustainable.”
“There’s a lot of expansion around the county, and we don’t know what the impacts of that are,” she said. “We haven’t quantified what that means.”
According to Aadland, people continue to use more and more water, and agricultural use is rapidly growing. There are currently about 1,000 agricultural irrigation permit applications in Otter Tail County – about double the number there were just a couple years ago.
“We use more water per person, and is that sustainable? I think they’re going to have to put more efforts on conservation in the future and look closer at how we allocate water…especially in areas (of Minnesota) where we know the use is not sustainable,” she said.
Exactly how, when or where water could be limited is yet to be decided.
The recent talk at the legislature, Aadland said, is an effort to better understand groundwater usage.
“We want to understand the water balance better, and how our human activities affect that balance for the long-term,” she said. “For sustainability into the future.”
If there were ever reason to believe that the water supply in the Perham area was in danger, or that the groundwater usage was affecting surface water, Aadland said, the DNR would step in and increase its monitoring efforts.
The main concern of the DNR, she said, is to protect the domestic water supply. For this area, that means making sure the expanding agricultural irrigation doesn’t interfere with domestic wells.
The county is singled out in the Freshwater Society report for its heavy use of groundwater for agricultural irrigation. According to the report, nearly 90 percent of Minnesota’s agricultural irrigation occurs in 13 counties, and of those, Otter Tail tops the list by far. In 2011, the county pumped 11.5 billion gallons of groundwater for agricultural irrigation. Next on the list was Dakota County, with a comparatively small 6.4 billion gallons.
Some of that is due simply to the large size of Otter Tail County.
The most heavily irrigated parts of the county are those with sandy soils, such as the type found around Perham, which quickly drain rainfall out of the reach of roots of farm crops.
Thus far in the county, there have been few disputes between neighbors over well usage, Aadland said. Anyone looking for assistance with a dispute, or for more information in general, may contact Aadland at 218-739-7576, ext. 243.