Record nitrate levels are wake-up call on Iowa water

The Des Moines Water Works provides drinking water for roughly 500,000 people in central Iowa, about one-sixth of the state’s population. The utility owns the world’s largest nitrate-removal system, larger than those operated by cities ten times the size of the Des Moines metro area. Last Friday, that facility was switched on for the first time in nearly six years when “levels of health-threatening nitrates hit records in both the Des Moines and Raccoon rivers.”

The news should be a wake-up call to state leaders: Iowa needs more than a voluntary strategy to reduce nutrients in our waterways. Not only are many of our rivers too polluted to support aquatic life, they are becoming more difficult and expensive to purify for drinking water. Nitrate levels are high in other parts of Iowa too, not only in the Des Moines area.

Perry Beeman broke the news Friday at the Des Moines Register’s website. I recommend clicking through to read the whole story, but here’s an excerpt.

“We are off our playing field. We haven’t seen this before,” [Water Works General Manager Bill] Stowe said.

“The issue is the quality of the water in the Raccoon and the Des Moines. This trend is absolutely off the scale,” Stowe said. “It’s like having serial tornadoes. You can deal with one, you can deal with two, but you can’t deal with them every day.”

“The state’s Nutrient Reduction Strategy, with it’s emphasis on the voluntary measure, clearly isn’t working,” Stowe said. “And our ratepayers are paying significantly to remove nitrates.” […]

Nitrates have been linked to blue-baby syndrome, in which infants suffocate, as well as to various cancers and miscarriages. The federal limit is 10 milligrams per liter nitrate in drinking water; both rivers have posted readings in the range of 20.

The Raccoon River hit 24 this week; the previous record was 22. The Des Moines was just under 18; the record was 14.2.

Stowe said tap water will remain safe, even with the unusual difficulty in finding water with lower nitrate levels to blend with the supplies running high. The $4 million nitrate-removal plant, installed in 1992 costs about $7,000 a day to run. So far, the utility is using four of the eight treatment cells where nitrates are stripped from the water. EPA had ordered Des Moines to act to remove nitrates after the contaminant exceeded the federal  limit.

KCCI-TV reported on Friday,

Nitrates are mainly used as fertilizers in agriculture. […]

The problem is worse because drought-stunted crops absorbed less nitrogen fertilizer last fall leaving it in soil. This spring’s heavy rain washed it into rivers.

The state unveiled a draft strategy on nutrients last November, but the proposals have not yet been implemented. Water quality experts from the U.S. Environmental Protection Agency and various environmental organizations, as well as some farmers, have criticized the nutrient reduction strategy for relying solely on voluntary measures by farmers and not setting numeric criteria for nitrogen and phosphorus in waterways. The EPA favors numeric criteria as part of any nutrient reduction strategy.

Susan Heathcote is water program director of the Iowa Environmental Council, a non-profit with which I’m involved. She issued this statement on May 10:

“Last November, Secretary of Agriculture Northey and other state government leaders released a strategy to reduce Iowa’s nitrogen and phosphorous contributions to the Gulf of Mexico by 45% statewide.”

“The announcement of record nitrogen pollution levels in the Raccoon River is a reminder that nitrogen and phosphorous pollution is also a serious threat to clean water here in Iowa.  It has been for decades. Despite this, Iowa’s Nutrient Reduction Strategy fails to set local nitrogen and phosphorous reduction goals for cleaner water necessary to protect the health and well-being of Iowans.

“Local pollution reduction goals are critical to motivating Iowa farmers and landowners to make the significant changes necessary to ensure clean water. Iowans should be confident efforts to reduce this pollution will protect those who want clean water for drinking and recreation in Iowa as well as downstream.

“Iowans should call on state government leaders to include local pollution reduction goals, timelines and accountability measures in Iowa’s strategy.”

Also on Friday, the Sierra Club Iowa chapter released the following statement.

Des Moines, IA – Record-breaking nitrates found in both the Raccoon and the Des Moines Rivers, the drinking source for hundreds of thousands of Central Iowans, should be a wake-up call for legislators before they adjourn for the session.

Des Moines Water Works’ reports of 24 mg/l in the Raccoon River and 17.87 mg/l in the Des Moines River (previous records were 22 mg/l and 14.2 mg/l respectively) represent totally unacceptable levels of nitrates in our drinking water. Nitrates can cause serious illness in humans.

“The responsibility for the nitrate levels falls on the Iowa Department of Agriculture and Land Stewardship and the Farm Bureau,” said Debbie Neustadt, Sierra Club Iowa Chapter chair. “We’ve had this problem for 40 years and industry continues to resist any form of regulation that would improve our water quality.”

In November 2012, the Iowa Department of Land Stewardship and the Department of Natural Resources released the Iowa Nutrient Reduction Strategy. The strategy is intended to reduce the amount of Nitrogen and Phosphorus that floats through the Mississippi River watershed (of which both the Raccoon and Des Moines Rivers are a part) into the Gulf of Mexico and contributes to the hypoxia (more commonly known as the “dead zone”) there. The Iowa “strategy” calls for targeting “…voluntary conservation measures, in conjunction with research, development and demonstration of new approaches.”

“The Iowa Nutrient Strategy is based on the false premise that Iowa is making significant progress in reducing water pollution and that no real changes need to be made in what thus far has been a voluntary and ineffective approach to nonpoint sources of pollution,” said Wally Taylor, Sierra Club Iowa Chapter Legal chair.

Legislation being considered during this session includes allocating $7 million for implementing the nutrient reduction strategy but requires no accountability to whoever receives the funds.

“How much more evidence do policymakers need to understand that voluntary conservation measures are ineffective?” said Neila Seaman, Sierra Club Iowa Chapter director. “Agricultural runoff is resulting in record nitrate levels of our drinking water.”

To my knowledge, Iowa Secretary of Agriculture Bill Northey has not made any public comment on the record levels of nitrates in the Des Moines and Raccoon rivers. He has ruled out any new regulations on farming practices to combat excessive nutrients in our water.

Any relevant comments are welcome in this thread.

UPDATE: The Des Moines Water Works released this statement on  May 13:

Nitrate levels in Des Moines Water Works’ source water reached historic levels last week, at 24 milligrams per liter (mg/l) in the Raccoon River and 17.87 mg/l in the Des Moines River. Currently at Des Moines Water Works’ river intake locations, the Raccoon River is reporting 21.04 and the Des Moines River is reporting 17.56 mg/l; however, higher numbers are being seen upstream.  This new record follows the continued upward trend of nitrate concentrations since fertilizer use and increased row-crop agriculture began in the mid-1960s. It has been calculated that last week’s nitrate load surpassed last year’s entire nitrate load.

Through extensive and expensive water treatment, Des Moines Water Works’ finished drinking water currently has a nitrate level of 7.5 mg/l. The Environmental Protection Agency’s (EPA) maximum contaminant level (MCL) for nitrate levels in finished drinking water is 10 mg/l.

In 1991, Des Moines Water Works built a $3.7 million Nitrate Removal Facility, which costs approximately $7,000 per day to operate. The facility has not been activated since 2007. Des Moines Water Works activated the Nitrate Removal Facility last Friday to keep finished drinking water nitrate levels below 10 mg/l.  Prior to starting up the facility, Des Moines Water Works staff managed the situation through blending of various water sources, including water from the Gallery (shallow ground water collector system), Maffitt Reservoir, Crystal Lake and Aquifer Storage and Recovery (ASR) wells.

“Des Moines Water Works staff has employed extensive efforts to mitigate nitrate levels, but because changes are not occurring in the watershed, we were left with no alternative but to activate the expensive Nitrate Removal Facility,” said Bill Stowe, CEO and General Manager, Des Moines Water Works.

Nitrate from fertilizer enters our water resources through run-off and agricultural tile drainage systems.

“The optimal solution to prevent nitrate concentrations from entering our source water is through watershed protection programs and good land management practices,” said Stowe. “However, the recently published Nutrient Reduction Strategy is inadequate in that it lacks vision, goals, measurable outcomes, or timelines for agricultural (non-point) discharges.  Without significant action, Des Moines Water Works will be forced to continue treating degraded source waters, and our customers will continue to pay for that extensive treatment in their rates.”

The greatest health risk posed by high nitrate concentrations is for infants under six months of age. Nitrate can transform into nitrite in the infant’s body, reducing the ability of the baby’s blood to carry oxygen. This may result in Blue Baby Syndrome. Des Moines Water Works’ finished drinking water nitrate concentration is currently below the level that will cause these health complications. If you are carrying for an infant, pregnant or have specific health concerns, you may wish to consult your doctor.

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  • I believe we are at an impasse here.

    Neither Iowa’s Legislature nor the Iowa Secretary of Agriculture has sufficient conviction or courage to call for mandatory steps to curb nitrate pollution of Iowa’s waters, which also contributes significantlhy to the Dead Zone in the Gulf of Mexico.  We have the scientific understanding of the problem and what it would take to solve it, but we are far from having the political will to make it happen.

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