MONEY

High nitrate levels plague 60 Iowa cities, data show

Donnelle Eller
deller@dmreg.com

More than 60 Iowa cities and towns have battled high nitrate levels in their drinking water over the past five years, evidence of a contamination problem that reaches across the state, state environmental data show.

Nitrate pollution affects Iowa's largest cities — Des Moines, Cedar Rapids, Cedar Falls and Waterloo — but also many of its smallest — Elliott, Griswold, Manchester and Woodbine.

The Iowa Department of Natural Resources data provide a snapshot of the cities reporting nitrate levels of 5 milligrams per liter or higher, a warning sign that nitrates are approaching harmful levels.

In fact, the state says water supplies of about 260 cities and towns are highly susceptible of becoming contaminated by nitrates and pollutants — about 30 percent of the state's 880 municipal water systems. And unlike Des Moines, many of those cities and towns have no facilities to remove excess nitrates, state officials said.

DATABASE: High nitrate level incidents in Iowa | Sites with nitrate testing above 5 mg

The issue of nitrate contamination drew heightened attention this spring when Des Moines Water Works sued drainage districts in three rural northwest Iowa counties, saying their tile lines exacerbate nitrate pollution.

"Many communities have been struggling with this issue for years and years," said Susan Heathcote, water program director at the Iowa Environmental Council. "It's not just people living in Des Moines who are concerned with reducing nitrates."

The federal government requires that nitrates not exceed 10 milligrams per liter of water — a level that without treatment can be deadly to infants 6 months and younger, the U.S. Environmental Protection Agency says.

Last year, 11 public water sources across Iowa — including municipalities, churches, residential care facilities and mobile home parks — exceeded the federal nitrates limit, according to a report released last week by the Iowa Department of Natural Resources.

Overall, there were 13 total violations, the lowest in the past decade, which Heathcote said is encouraging. But she worries about the financial impact if cities are forced to install new equipment to reduce nitrates, especially small communities already hammered by dwindling jobs, populations and businesses.

"Some of these communities are struggling just to survive," she said.

Identifying the sources

The EPA says nitrate threats can come from several sources, including farm fertilizer runoff, septic system leaks and movement of naturally occurring nitrates in the soil.

Des Moines Water Works has blamed farming for the high nitrate levels that it has paid more than $1 million since 2013 to treat. In its lawsuit, it says the drainage tiles used to make land more productive in Calhoun, Buena Vista and Sac counties act as a conduit for nitrates to flow more freely from farm fields into Iowa waterways.

The Des Moines utility argues that nitrates from farm drainage tiles run up bills for Iowa cities, towns and their customers. The utility has been forced to run expensive nitrate removal equipment since April 17, when levels in the Raccoon and Des Moines rivers spiked over 15 milligrams per liter.

Across the state, many communities get below the federal cap by blending water from several underground wells or river collectors with differing nitrate levels. Still, that might not be enough for some towns, which could be forced to invest millions of dollars in new equipment or wells to ensure drinking water is safe.

DATABASE: High nitrate level incidents in Iowa | Sites with nitrate testing above 5 mg

"We have over a dozen wells on the Des Moines River, and on any given day, some of those might register low or high nitrate levels," said Luke Nelson, Boone's administrator. "We do a lot of tests and pull water from the best sources."

The north-central Iowa community — and Xenia Rural Water District, which buys water from Boone — warned residents last month that nitrate levels exceeded the federal cap. Boone and Xenia asked parents to not use the water for baby formula, juice and other food given to infants.

This is the first time in 15 years that Boone has had to issue a warning for high nitrate levels, which the city blames on recent massive rainstorms.

The notice remained in place last week, although nitrates were nearing safe levels.

No removal equipment

Boone, Cedar Rapids, Griswold and other Iowa cities have no nitrate removal equipment they can fall back on when nitrates rise.

Nick MacGregor, Griswold's city manager, said investing in nitrate removal equipment would cost taxpayers about $1 million.

Instead, the community is working with nearby farmers to plant up to 500 acres of cover crops over three years. Crops such as cereal rye should help absorb nitrogen in the fall and spring, when fields aren't covered with traditional corn and soybeans that use the nutrient to grow.

MacGregor hopes the partnership will help protect the town's water and avoid big infrastructure improvements. Other options include drilling a new, expensive well.

DATABASE: High nitrate level incidents in Iowa | Sites with nitrate testing above 5 mg

The state has a $13 million program that's available to communities that need to invest in new water infrastructure. But it's a revolving loan program and doesn't provide grants.

"We have a general operating budget of $1.5 million, so to a city like us, a million dollars is a pretty big deal," he said.

Nelson said Boone also will likely look to area farmers as well to help improve water quality — and potentially avoid other high-cost solutions for the city's 13,000 residents.

The nitrates solution

Weather can play a large role in nitrate levels, along with land use, drainage, soil types and other factors. Farm groups have argued that reducing nitrate levels is extremely complex and will require increased conservation efforts from most of the state's nearly 90,000 farmers.

Cutting nitrate and phosphorus levels is expected to be costly, an estimated $1.2 billion annually over five decades. Conservation practices include building wetlands, bioreactors and saturated buffers and expanding cover crop usage.

Nelson said Boone has no more room to raise water and sewer bills. Rates are already high compared with other towns, thanks to other state and federal regulations.

"It costs more and more to produce water and treat effluent each year," he said.

Heathcote and Bill Northey, Iowa's secretary of agriculture, say it can be easier for small towns to build collaborative efforts than for cities such as Des Moines.

DATABASE: High nitrate level incidents in Iowa | Sites with nitrate testing above 5 mg

For example, the watershed that feeds the Raccoon River, a drinking water source for 500,000 Des Moines area residents, encompasses 3,625 square miles, the utility's lawsuit states. That's 2.3 million acres.

The farmland changes that Boone, Griswold and other rural communities need are much smaller, said Heathcote, the Iowa Environmental Council's water director.

And the motivation to find solutions is stronger.

"Farmers are part of the community in these small towns. You probably go to church with people in town, your kids all go to school together. You're much more motivated to resolve the issue," she said.

Northey agreed. "There are a lot of willing partners," he said. "No one is forcing it to happen, because it's in everyone's best interest."

Replicating that experience in bigger cities, with larger watersheds and many more land users, is more challenging.

Relief through litigation

The Des Moines utility said in March that it sued Sac, Buena Vista and Calhoun counties because the state's plan to reduce nitrogen and phosphorus in its waterways was ineffective.

The Des Moines utility wants to force rural drainage districts to receive permits under the federal Clean Water Act. Farm activities are mostly exempt from federal oversight.

Success could push drainage districts to install wetlands and require farmers to adopt conservation practices that help reduce nitrogen and phosphorus levels in Iowa waterways.

Conversely, Iowa's Nutrient Reduction Strategy, designed to reduce nutrients that contribute to the Gulf of Mexico's dead zone, is voluntary and has no deadline for reaching the state's goal of a 45 percent reduction in nitrogen and phosphorus levels.

DATABASE: High nitrate level incidents in Iowa | Sites with nitrate testing above 5 mg

Gov. Terry Branstad said earlier this year that Des Moines had declared war on rural Iowa. Bill Stowe, Des Moines Water Works' CEO, has said urban leaders are tired of paying for farm pollution.

The lawsuit has "caused frustration on both sides," said Nelson, Boone's city manager. "But I think it's also raised awareness about water quality."

Northey said farmers in northern Iowa haven't shut the door on working with Des Moines Water Works.

"Farmers, with the help of farm groups and private industry, are working on this on their own, but they'd welcome more people to the effort," he said.