Groundwater use by cities is wringing it out. Potential fixes: conservation, a pipeline, and 'gray water'
Sometime this fall, probably soon, White Bear Lake will reach its lowest level on record -- lower than the mark it reached only two years ago.
But the course of the shrinking lake can't be entirely blamed on this summer's drought.
It also involves a man-made threat to one of the metro area's brightest jewels, and other lakes like it: the use of underground water for lawn watering, bathing and drinking.
Since 1980, growing communities in the northeast metro have more than doubled the volume of water they pump from the Prairie du Chien aquifer beneath them, pulling water from White Bear Lake and other lakes nearby, according to Perry Jones, a U.S. Geological Survey (USGS) hydrologist.
Jones just completed a two-year study of groundwater-surface water interactions, which found that since about 2003, White Bear continued to drop even in wet periods -- a significant new trend. One reason: The city of White Bear Lake and nine surrounding communities pumped 2.6 billion gallons of water from the Prairie du Chien aquifer in 1980, but 6 billion in 2008. Most of that has been for residential use, while industrial and commercial use, including golf course watering, remained steady. The study found that it would take annual rainfall 4 inches above normal just to stop the lake's shrinkage.
White Bear and the surrounding lakes and streams are particularly prone to shrink quickly due to pumping because the sandy soil beneath them allows surface water to drain readily into the aquifer. White Bear Lake, in particular, is deep enough to have an easy exchange with the aquifer.
As a result, shoreline residents will have to continue dragging their docks hundreds of yards to reach water -- or trying to find them in tall brush -- while swimmers at the main public beach encounter a steep drop off at what used to be a long, shallow walk-in, and dozens of slips at the downtown marina remain vacant, with mud having replaced boats.
"I'm thinking White Bear Lake is reaching a 'new normal,'" said Molly Shodeen, a metro-area hydrologist for the Minnesota Department of Natural Resources.
A big shallow end
White Bear dropped more that 5 1/2 feet between early 2003, when it was last at its "ordinary high water" level, and Nov. 13, 2010, when it reached the lowest level ever recorded. It rose partway back last year, but lost all of that in recent months, and last week was within about 2 1/2 inches of the record low again.
The drop has left residents reeling. Some have obtained permits from the DNR to mow the plants that have grown on the sandy lake bottom that now makes up their vast and growing front yards.
Lifelong resident Jan Holtz Kraemer said neighbors don't encounter each other as much as they used to, in the old days when "life was good and docks were short." In fact, she now goes down to the lake when she wants to be alone, she said; it's much quieter without jet skis and boats on the water. This summer she turned her White Bear Lake flag upside down to signal distress, until her psychiatrist advised her she wasn't responsible for the dwindling lake.
"The drought hasn't helped," Kraemer said. "I wish it were just God's fault. But it isn't.''
While the problem has been vivid at White Bear Lake, aquifer pumping has the potential to create much wider problems.
Shoreview's Turtle Lake, and others extending into Washington and Chisago counties, have seen similar drops in the last several years; South School Section Lake, a small lake in Washington County, dropped nearly 12 feet between a 1997 peak and the latest reading, last April.
"The metro area is still water-rich," said Keith Buttleman, an assistant general manager at the Met Council, which oversees long-range water demand and planning for the metro area. "However, it's not evenly distributed, and there are a number of areas where if the trends established over the past 20 to 40 years continue, there will be fairly serious problems."
Looking for fixes
But meanwhile, many communities, from Woodbury to White Bear, have already jumped into water conservation programs, from alternate-date lawn sprinkling to increased billing. Water use in the city of White Bear Lake dropped 20 percent in the last five years, said city manager Mark Sather. Sather said increasing the cost of water was one reason. Another is an aging population with smaller households.
"We're just seeing people use less water," Sather added. "They're becoming more aware of the issue."
Jones said one promising strategy -- indeed, an aim of the USGS study -- is to identify wells that draw the highest concentrations of lake water and move them farther away from the aquifer.
Other community groups are thinking more grandly. Lake associations along Snail and Gilfillan lakes in Shoreview have arranged to divert water heading from the Mississippi River into the city of St. Paul's reservoir system; now it would augment their lakes.
A citizens' task force looking at solutions for White Bear Lake is considering a pipeline that would carry water from the Mississippi River and filter out invasive critters before dumping it into the lake. Another idea: pumping and filtering water from nearby Bald Eagle Lake, which doesn't lose appreciable water to the aquifer. Yet another: building a wastewater treatment facility in the northeast metro, cleaning the water there instead of sending it to the Pig's Eye plant in St. Paul, and pumping it into the aquifer near White Bear.
All of them, however, show the scale of challenges facing a region long accustomed to plentiful water.
"There are no cheap fixes," Shodeen noted. "They're all very expensive."
Bill McAuliffe • 612-673-7646