WASHINGTON - Wells and lakes across Minnesota are at risk from fertilizers and pesticides running off the state's expansive farmlands, according to a detailed new inventory released Thursday.

Shallow wells in parts of Minnesota have four times as many unhealthy nitrates and nitrites as normal groundwater, and many lakes have levels of potentially harmful aquatic algae and organic carbon that are more than double those of its neighboring states, according to the Environmental Working Group (EWG), a Washington watchdog.

The findings, some of the most comprehensive to date, laid bare one of Minnesota's most delicate balancing acts: How to simultaneously protect the state's natural resources and agricultural economy.

"The dangers to public health will increase, or the costs will increase to keep drinking water safe," said Craig Cox, an EWG vice president, who co-authored the study with scientist Olga Naidenko.

Advocates for Minnesota farmers disputed Cox's conclusions.

"We don't have a drinking water problem in Minnesota," said Warren Formo, executive director of the Minnesota Agricultural Water Resource Center, which represents 17 Minnesota farm groups. Farmers have worked to control fertilizer and pesticide runoff, industry officials said.

"We've got a vital stake in protecting resources," said Kevin Paap, Minnesota Farm Bureau president. "We live on the land, and we drink the water."

But Cox said the issue needs urgent attention.

"We're in an unprecedented situation for [high] commodity prices," he said. "There is pressure to extract every bushel from every acre, as we lose tools to manage the problem."

University of Minnesota water researcher Deb Swackhamer agreed. "We are seeing an increase in public and private wells that are above the health limits for nitrates," she added. "We thought this was a 1950s problem."

Facing underlying problems

Water in Minnesota is generally cleaner than in many parts of the country because of the state's Clean Water Legacy law. But Cox and Naidenko said the underlying pollution problem remains unsolved.

In many cases, they said governments lack the power to compel changes in agriculture and farmers lack the financial incentive. "The Clean Water Act provides no authority to provide improvements to the vast majority of U.S. farms," Cox said.

What's left, he said, are subsidies for conservation and other pollution control efforts in the five-year farm bill now being negotiated in Congress. But many of those incentives face deep funding cuts because of the federal budget deficit.

In January, Minnesota Gov. Mark Dayton signed an agreement with the U.S. Environmental Protection Agency to pilot what could become a national program of voluntary water quality standards for farmers. The voluntary standards are designed to encourage participation in a state where half the land mass is devoted to crops.

Reexamine subsidies?

While the EWG sidestepped mandates, it advocates changes to some of the most popular and historically untouchable farm subsidies. "Congress should end direct payments, reduce subsidies for farm insurance programs and refuse to create new farm entitlement programs that encourage all-out production," the group says. EWG suggests increased funding for buffers that block runoff and wetlands that filter chemicals.

EWG found that roughly one in nine domestic wells in Minnesota contained unsafe levels of nitrates, a substance that can lead to health problems, including cancer, in humans.

Cox added that, while domestic wells used by individuals pose the greatest health risk, health issues also extend to communities that rely on surface water because dangerous chemicals used to disinfect drinking water sometimes end up in tap water.

Despite reservations in some circles, Naidenko predicted a positive response to the report for a simple reason: "People want clean and good tasting drinking water."

Jim Spencer • 202-408-2752