Pricey -- $600 million -- solutions for thirsty White Bear Lake

Three potential solutions aimed at restoring water levels of White Bear Lake — two of them estimated to cost more than $600 million — are being proposed in what could be part of sweeping changes in how cities across the metro area get their drinking water.

In a draft report released Wednesday, the Metropolitan Council outlined options for augmenting White Bear Lake with water from the Mississippi River. It also spelled out ways that up to a dozen northern Ramsey County communities could shift their heavy reliance on groundwater from the overtaxed Prairie du Chien aquifer to the more abundant surface water from the Mississippi.

While the draft report focuses on the northeast metro and White Bear Lake, which has lost one-fourth of its volume over the past decade, the Met Council also has begun several other regionwide studies to explore ways to restore balance to water sources and ease pressure on the aquifers.

More than 70 percent of the region's water supply now comes from the ground, compared with about 20 percent in the 1940s and 1950s, before suburban growth. But that rate of mining is not sustainable, said Ali Elhassan, the council's water supply planning manager. As seen in White Bear Lake, it has ruinous results for the quality of life and the local economy.

"White Bear Lake is the bellwether," Elhassan said. "It's showing us what will happen elsewhere in the region if we continue current water-use practices."

The Metropolitan Council is evaluating three basic approaches to restore White Bear Lake, based on the finding that St. Paul's regional water system has 30 million gallons a day in extra capacity to supply communities to its north for the next 25 years. The cost to do that, however, grows the farther away the communities are from the system.

The proposals, and their estimated price tags:

• Expand St. Paul's water system to deliver treated water from the Mississippi River directly to northeast metro communities.

The council identified three ways of doing that: expand only to North St. Paul, the least expensive option at $5.2 million; expand water service to the six closest communities to St. Paul (North St. Paul, Vadnais Heights, White Bear Lake, White Bear Township, Mahtomedi and Shoreview), at a cost of $155.4 million, or expand St. Paul's Lake McCarrons water treatment plant to serve five of those communities (North St. Paul would be part of a separate expansion), along with seven others (Lino Lakes, Centerville, Hugo, Forest Lake, Columbus, Circle Pines and Lexington). That option would be the most expensive at $623 million.

• Build a water treatment plant at Vadnais Lake to receive water from the Mississippi to distribute to surrounding communities.

This service, if limited to Mahtomedi, Shoreview, Vadnais Heights, White Bear Lake and White Bear Township, would cost $230 million. Phasing in water service to the other seven communities (Lino Lakes, Centerville, Hugo, Forest Lake, Columbus, Circle Pines and Lexington) would bring the cost to $610 million.

• Pump filtered water, about 2 billion gallons a year, from the Mississippi to White Bear Lake by way of the chain of nearby lakes.

Because the Mississippi River and Vadnais Lake have zebra mussels, this proposal also would require a filtration system, bringing the cost to $50 million. The St. Croix River was considered as another possible source but eventually eliminated because of the distance, the need to essentially pump the water uphill and regulatory concerns related to its status as a federal Wild and Scenic River.

Merely augmenting White Bear Lake, the draft report cautions, offers no guarantee that lake levels could be maintained once they are restored, or that other nearby lakes and aquifers would benefit.

The next step in the process is a review of the draft, which includes a public meeting Thursday night at Century College in White Bear Lake. The alternatives and the question of how to pay for them will be more thoroughly evaluated and addressed by the time a final report is done in October.

The water level at White Bear Lake plummeted to an all-time recorded low in January 2013, with a depth of just under 919 feet above sea level. Its typical depth is about 925 feet.

While a wet spring and early summer have recently replenished the lake to 922 feet, a level not seen since mid-2008, nature's fix is expected to be temporary.

Jim Anderson • 651-925-5039 Twitter: @StribJAnderson