An important bill that has the potential to help ducks rebound in Minnesota was heard Thursday morning by a House panel in St. Paul.

The measure, which was passed by the Environment, Energy and Natural Resources Policy and Finance Committee, is intended to restore the health of some of the state's 4,000 shallow lakes.

Critical to ducks, these lakes -- defined as less than 15 feet deep and smaller than 50 acres -- are no less important to a broad array of other wildlife and, ultimately, to the health of the state's drinking water.

Sponsored by Rep. Denny McNamara, R-Hastings, the measure significantly speeds up the process by which a shallow lake can be temporarily "drawn down,'' or de-watered, in an attempt to kill rough fish such as common carp, and to reinvigorate desirable aquatic plants such as sego pondweed and wild celery.

The bill is a long way from becoming law, but the fact that McNamara is carrying it signals that the House Republican caucus is favorable to its passage, or at least open to discussion of that eventuality.

Because of drainage caused largely by agriculture, but also by development and the inexorable march of humankind across the state since settlement, Minnesota's original hydrology -- the flow and transfer of its water -- has been wildly mutated.

In the state's southern and western farmlands, for example, about 90 percent of original wetlands have been ditched and drained. As a result, rainfall and snowmelt are compressed into remaining sloughs, wetlands, rivers, streams and lakes as never before.

Many of these wetlands and small lakes, as a consequence, are for the first time "connected,'' allowing for the transfer from one to another of unwanted species such as common carp.

Additionally, on this revised landscape, water surges that follow heavy rains oftentimes kick up wetland and shallow-lake levels by multiples of feet virtually overnight -- a common occurrence in southwest Minnesota at Heron Lake, for instance, where water-level jumps as high as 7 feet have been recorded after big downpours.

Disasters such as these -- routine today in Minnesota -- lie at the heart of the state's duck problem. Not only do these surges allow for the transfer of carp, they kill any chance that desirable aquatic plants can reassert themselves.

That's because these plants require fairly specific, stable water depths to thrive, and also require that the lakebeds in which they grow periodically dry up.

Historically in Minnesota, this occurred during periods of drought, when plant seeds lay dormant. Returning rain in turn nurtured the plants, which attracted and nourished mallards, teal, gadwall and other ducks, particularly during spring and fall migrations.

Today, Minnesota seems light years removed from such natural progressions, given the turbid and carp-infested state of our remaining wetlands and shallow lakes.

McNamara's bill seeks to reverse these misfortunes by giving the Department of Natural Resources commissioner streamlined authority to grant temporary draw-down permits to manage shallow lakes for fish, wildlife or other ecological purposes.

Not only would ducks and other wildlife benefit, flood retention capability could be significantly increased. In 2007, for example, 1,875-acre Geneva Lake in Freeborn County had been drawn down using a water control structure designed and installed by Ducks Unlimited.

The following spring, flooding was intense in the area. But because Geneva was in temporary draw-down, it provided 3,000 acre-feet of flood-water storage, reducing water problems downstream in towns such as Austin.

In McNamara's committee Thursday, questions were raised about possible interference with the property rights of landowners surrounding shallow lakes being considered for draw-down.

A reasonable issue to raise. But not really a concern, because public input would be ensured under the proposal, and because most shallow lakes recommended for draw-down are in such crummy shape, and so small, that nearby landowners would welcome their improvement.

Additionally, under the bill, the draw-downs can occur for only two years. So the lakes would be quickly back to their previous levels.

McNamara's proposal is House File 2870. If you care about clean water, and particularly about ducks and other wetland wildlife, call your legislator and ask him or her to support the plan.

Otherwise, don't complain next duck-hunting season, or the next or the next, about the empty skies that now seem so common over Minnesota.

Dennis Anderson •