Several state agencies are warning of more fish kills and contaminated drinking water if cash-strapped farmers delay emptying their manure lagoons this fall.

Dairy farmers store their cow manure in lagoons, and in the fall, they typically empty those lagoons onto their fields as free fertilizer.

This year, though, with milk prices at historic lows and the recession hitting farmers hard, the state is worried that some farmers won't be able to afford to have the manure spread.

The University of Wisconsin-Extension, state Department of Natural Resources and the Department of Agriculture, Trade, and Consumer Protection are urging farmers to properly manage their manure and not take shortcuts. They say that if manure lagoons fill up, farmers will be faced with the choice of allowing them to overflow or spreading manure atop frozen fields, where it could run into streams and rivers, killing fish.

Manure runoff is a concern for the Wisconsin Valley Improvement Co., which operates reservoirs on the Wisconsin River system, including the Big Eau Pleine.

From Feb. 7 to Feb. 11, the WVIC measured very high levels of nutrients coming into the Big Eau Pleine after a warm spell hit Marathon County. WVIC thinks manure, spread atop snow-covered fields, ran into the streams and rivers that empty in the Eau Pleine during the warming.

That, said WVIC Director Sam Morgan, might have been the nail in the coffin that caused a 70 percent to 80 percent fish kill on the reservoir last winter. The reservoir also suffered from a five-year drought and a badly-damaged aerator.

Farmers' conundrum

Spreading manure on fields in the fall provides great fertilizer for next year's crops. But pumping the manure can cost plenty, and dairy farmers are battling milk prices that are down 70 percent from a year ago, according to the U.S. Department of Agriculture. Dairy farmers now are getting about $12.70 per 100 pounds of milk, down from $18.20 a year ago and from $20 in January 2008.

UW-Extension's Kevin Erb estimates that it costs $100 to $250 per cow, per year to pump and spread manure. That would cost a farm with 200 cows, for example, $20,000 to $50,000 a year.

Gary Halopka sympathizes with the farmers. His company, Halopka Pumping of Dorchester, pumps and spreads manure for dozens of farms across central Wisconsin.

But right now, Halopka is not getting paid. He has done work for farmers dating back to the spring, and several have not been able to pay him. He's forecasting as much as $300,000 in unpaid work on the books by the end of the year.

"I don't know when I am going to get paid," he said. "How many times am I supposed to do that and stay in business?"

Halopka can't tell yet whether farmers are filling -- or overfilling -- their lagoons or whether business will pick up again later in October. The first half of the month's rains left fields too muddy for manure to be spread.

Either way, he's concerned. The window for spreading manure is closing quickly because the ground typically freezes in mid to late November.

Set for the winter

Not all farmers are concerned about their lagoons overflowing.

Anthony Totzke just last year installed a 2.2 million gallon lagoon on his town of Frankfort farm that is built to last 16 months without needing to be emptied. He already has spread 400,000 gallons this fall. Cash is tight for him, too, but even if he is unable to spread any more, he still has about 1.5 million gallons of lagoon space, which should last through the winter, he said.

Totzke said it's usually beneficial to have a manure lagoon, because it is free fertilizer for fields. But experts say Totzke is unusual; many farmers just can't afford to pay for manure spreading right now.

"When push comes to shove it's not that they don't want to do the right thing, it's just they might not have the cash," said Tom Cadwallader, agricultural development agent for Marathon County.