Poisoned Waters - Alt Version

Nitrate is a main pollutant in Minnesota waters. The main source of the chemical salt is nitrogen fertilizer, a pillar of conventional production agriculture — both the nitrogen in animal manure applied to fields, and synthetic nitrogen fertilizer.

Crops thrive on the nitrogen – but at far too high a cost, many say.

Minnesota has spent untold hours and hundreds of millions of dollars over decades studying and fighting the dangerous nitrate polluting its drinking water, streams and rivers. Many of more than 30 recent programs on nutrient reduction in our waters involve nitrate.

There's been precious little progress on cutting nitrate to show for it, with hundreds of thousands of Minnesotans still living in communities with elevated nitrate levels found in their water.

State and federal standards place nitrate at levels at or above 10 milligrams per liter beyond the legal limit. But there's a push to lower those standards, given growing research around links to cancer and other damaging health impacts from drinking water with nitrate at levels below 10 milligrams and even below 5 milligrams.

Toxicologists at the Washington DC-based nonprofit Environmental Working Group determined a health guideline significantly below 1 milligram of nitrate per liter would best protect people. The group has acknowledged that kind of strict limit is unrealistic as a federal standard, but the 10 milligram limit needs to be lowered, it says.

Levels at 3 milligrams per liter and above are what the Minnesota Department of Health and many other state agencies consider to be caused by human activity, not nature.

Southeast Minnesota, with its heavy agriculture and vulnerable, porous karst geography and sinkholes, is one of the most vulnerable parts of the state for nitrate pollution.

Dodge, Goodhue, Fillmore, Houston, Mower, Olmstead, Wabasha and Winona counties are in crisis, according to an emergency request filed in April by the Minnesota Center for Environmental Advocacy and the Minnesota Well Owners Association, asking the U.S. Environmental Protection Agency to take emergency action under the Safe Drinking Water Act. Whether the EPA takes this on remains to be seen.

State and local authorities have failed to stop nitrate from polluting the groundwater, the groups argue, and it's created an "imminent and substantial endangerment" to public health. About 80,000 residents in those counties rely on private wells for their drinking water in that area and about 300,000 use public water systems, according to the request.

Nitrate pollution continues despite the hundreds of millions of dollars spent across Minnesota over decades, from a host of federal and state sources.

The money has funded a range of efforts including Nitrate Smart farmer trainings, water research, multiple conservation programs, source water protection work, guidance for farmers and expensive treatment systems in cities like Hastings, Cold Spring and Adrian so people can safely drink their tap water – a long list the state follows in its five-year progress reports to cut nitrogen and phosphorous levels in waters.

A key funding source has been the state's Clean Water Fund, part of the sales-tax funded Legacy Amendment. That fund alone has spent at least $148 million related to the nitrate problem since 2010, according to a Star Tribune analysis.

None of that spending appears to have made a dent in the overall demand for nitrogen fertilizer, with sales steadily climbing. As cropland has expanded, farmers bought a record 824,000 tons of nitrogen fertilizer in 2020, according to sales tracked by the state Department of Agriculture. That's the last available year of data.

Minnesota's community drinking water supplies – the water systems for cities, towns and mobile home parks – are regularly tested to assure nitrate levels are below the state and federal health limit of 10 milligrams per liter of water. The Minnesota Department of Health collects the data.

Despite significant work, Minnesota has only seen pockets of progress with community water supplies. Even as some water supplies addressed the highest nitrate concentrations, a Star Tribune analysis of the Health data from 1993 through 2022 show Minnesota's 950 community water systems consistently registered nitrate levels of at least 3 milligrams per liter 11% or more of the time.

About 176,000 Minnesotans still lived in communities with an average readings above 3 milligrams as of 2022 – an 18% increase from 2021.

Additionally, violations of federal nitrogen contamination standards across Minnesota have increased gradually, and consistently account for about 5% of violations in the EPA's Safe Drinking Water Information System since 2013. The violations are detected through mandated regular monitoring of water supplies and reported to the state and EPA. This year's volume of reported nitrate violations has already surpassed 2022.

At least a half-million Minnesotans in hundreds of communities live in areas where water has tested at least once for elevated nitrate levels in the past decade.

More than 400,000 of those are in 100 communities with at least one nitrate test over 3 milligrams per liter since 2013, according to a Star Tribune analysis of community water system data tracked by the state Department of Health.

These affected Minnesotans are mostly spread across central and southern parts of the state.

People who rely on their own private wells for drinking water are completely on their own to get tested and find remedies. There's an estimated 980,000 private wells around the state.

Nearly 350 townships with private wells tested for nitrate returned results of at least 3 milligrams per liter since 2013, based on results from a voluntary township nitrate testing programs tracked by the state Department of Agriculture.

The volunteer private well tests the Department of Agriculture has helped run show disturbing contamination. In southeast Minnesota from 2008 through 2018, about 8% to 15% of the hundreds of private wells tested each year showed nitrate pollution above the 10 milligram health limit. In 2021, about 30% of those private wells showed results above 3 milligrams. In the 14-county Central Sands part of the state from 2011-2018, about 3% to 5% of the hundreds of private wells tested each year were polluted with nitrate above the 10 milligram limit.

It's not just drinking water being polluted. The nitrate runs into lakes, rivers, streams and creeks, contaminating water for fish and other aquatic life. The nitrate flows south in the Mississippi River helping drive the huge oxygen-starved Dead Zone in the Gulf of Mexico. As part of the Hypoxia Task Force of states up and down the river, Minnesota as pledged to cut the nitrate in the Mississippi by 20% by 2025. But nitrate has actually risen in spots, as it has in most of the state's major rivers.

Lawmakers directed the Minnesota Pollution Control Agency in 2010 to set limits on nitrate to protect fish and aquatic life. It hasn't happened. It would be too expensive for small wastewater treatment plants, and wouldn't effectively reduce the nitrate from the farms it has no power to regulate, the agency told the Star Tribune.

About 5% – or 165 miles – of Minnesota's rivers and streams used for drinking water are impaired by nitrogen and/or phosphorus as of 2022, meaning they don't meet federal quality standards. In all, the EPA lists nearly 800 Minnesota waterbodies including rivers, lakes, creeks and streams as containing nitrogen and phosphorus pollution.

Sources: Environmental Protection Agency, EPA Safe Drinking Water Information System, Minnesota Pollution Control Agency, Minnesota Department of Health, Minnesota Department of Agriculture, Environmental Working Group, Star Tribune reporting and analysis