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Get ready for more White Bear Lakes: Two new looks at groundwater depletion

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Two new reports on Minnesota's groundwater resource deserve more attention than they've been getting.

One, from the U.S. Geological Survey, updates and elaborates its findings that falling water levels in White Bear Lake are largely attributable to increased groundwater pumping by city water systems to the north and west.

Another, from the Freshwater Society, sets that lake's predicament in the context of a much larger problem — a huge increase in groundwater pumping all across Minnesota during the last quarter-century.

From 1988 to 2011, the report finds, pumping by Minnesota's largest groundwater users — municipal systems and agricultural irrigators, for the most part — grew by 31 percent. That's far faster than population, which rose by 24 percent.

And this statistic may significantly understate the true trend, but nobody really knows. It is drawn from permit records maintained by the Minnesota Department of Natural Resources, and you have to pump an awful lot of water before a permit is required: Wells serving private homes, most businesses and lots of non-irrigating farms aren't counted.

Also, the department didn't start keeping the records on which the Freshwater Society analysis is based until 1988 — and still makes little effort to enforce the permit and reporting requirements against users who choose not to comply.

'Areas of concern' statewide

The impacts of soaring consumption are showing up quite clearly, not only in White Bear Lake but in 15 other places designated by the DNR as "groundwater areas of concern."

By definition, these are 16 places "where communities have sought planning or regulatory help from the DNR, where groundwater contamination is known to exist, or where hydrologists have long suspected pumping is, or could become, unsustainable." In other words, where somebody with a close-up view of the situation sees a big problem taking shape.

In two of those areas the DNR is preparing to make first use of its authority to create "groundwater protection areas" as way of addressing the impacts of irrigation pumping:

  • The Bonanza Valley north of Willmar, where summertime groundwater levels have been dropping significantly in recent years, and where the DNR has been concerned for at least four years that irrigation pumping has reached unsustainable levels.
  • A region around Park Rapids where irrigation pumping threatens to deplete the Straight River and also appears to be introducing nitrate contamination into municipal wells.

Elsewhere: In Bemidji, the issue is chemical contamination from a former sanitary landfill that is now a Superfund site. In Perham, irrigation is returning nitrates to the groundwater. In Rochester and along Interstate 94 corridor between the Twin Cities and St. Cloud, the concern is that rapid residential development may oversubscribe each region's groundwater resources.

And on it goes, in places as small as Luverne and as big as Marshall, Mankato and Moorhead.

And yet even today, the report shows, little meaningful effort is being made to manage groundwater withdrawals or to measure how much is actually left.

Consider: In the eight communities whose groundwater pumping has been linked to White Bear Lake's decline, withdrawals have more than doubled since 1980, from an average 1.7 billion gallons per year to 3.7 billion. But they could have gone all the way to 4.8 billion before exceeding the levels set in DNR permits.

Where the groundwater goes

Nearly three Minnesotans in four drink water that came from a well rather than a river or lake. Even in the Twin Cities metro area, with Mississippi River water feeding the big-city systems in Minneapolis and St. Paul, groundwater is 70 percent of the mix. Thirty years ago it was half; 70 years ago it was 10 percent.

A little over half the groundwater pumping tracked by DNR is done to supply city water systems. About a quarter is used in agricultural irrigation, and about one-fifth by industry. The remainder is scattered among such uses as livestock operations, snowmaking, sewage treatment and golf courses. (Though often singled out as water wasters, golf courses pump just 2 percent of the total.)

However, this pie chart is being reconfigured by the rapid expansion of agricultural irrigation. While municipal systems increased their pumping by 33 percent from 1988 through 2011, irrigation pumping increased more than twice as fast, rising 73 percent over the period. Industrial pumping, meanwhile, declined somewhat.

Again, these stats refer to reported pumping, and Minnesota requires permits and reports only for enterprises pumping in excess of either 10,000 gallons a day or a million gallons a year.

Those are mind-boggling and perhaps meaningless numbers to most people — including me — who have no idea how much water  is used by, say, a typical modern household. So I did a little research and back-of-the-envelope ciphering.

I drink from a private well now (and, oddly, am more attuned to conserving water than I was when I had to buy it from the city of Minneapolis). But when I was on the city supply, watering my lawns and sidewalks, washing my cars and raising a teenager who might shower for a half-hour at a time, and never remembered to jiggle handle when the toilet was running on, my bill typically showed two or three "units" of water per month  — a unit being 748 gallons in the Minneapolis system.

At a full three units every month, our  total annual consumption would round up to 27,000 gallons. Which means that  if you happen to have a well in, say, the Bonanza Valley, you can pump nearly 40 times as much as our heedless household without having to get a permit, file a report or pay a penny for the public resource you withdraw.

If you do take out a permit, you can pump up to 50 million gallons a year for your minimum fee of $140 — a figure the Freshwater Society observes is "far too low to discourage waste or over-use."  

The cost of change

I'm dwelling on the dollars here because it's clear that something has to change in Minnesota's management of groundwater and those changes will carry costs — costs that no doubt will be assailed as excessive and needless even if they are, in fact, measly and unavoidable.

Writing in the Pioneer Press the other day, the Freshwater Society president (and former legislator and DNR commissioner) Gene Merriam offered this perspective on a proposal to expand the state's network of groundwater monitoring wells:

The $6.1 million per year sounds like a lot of money, but the fees increases will not be an undue hardship for water users.

For residential water service, the state fee would increase from a range of $3.50 to $8 per million gallons under the current fee schedule, to $15 per million gallons under the new structure. But the increase — assuming it all is passed on to consumers — would boost water costs for a household by only about $1 per year. That is less than the cost of a single bottle of water in most vending machines.

For agricultural irrigation, the state fee would go from an average of $10 per million gallons to $22. Many industrial users pumping from their own wells would pay $30 per million gallons.

The society titled its report "Minnesota's Groundwater: Is Our Use Sustainable?" and answers the question by saying that pumping has already reached unsustainable levels in a few areas and threatens to do the same in a few more before long.

But this is not really a mixed picture. The trend lines on groundwater withdrawal are steady and steep. Responses so far have been scattered and inconsistent. And if not for the prominence of White Bear Lake, the entire subject of groundwater depletion might still be struggling for a little public awareness.


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