Posts Tagged ‘Nitrate’

May 23, 2013

Managed Irrigation Requested, Even as Drought Conditions throughout Central Iowa Improve

Des Moines Water Works is asking metro area customers – residential and commercial – to manage seasonal irrigation for the next several weeks, even as drought conditions throughout the state continue to improve.

Due to the recent historic nitrate concentrations found in the Raccoon and Des Moines Rivers, Des Moines Water Works is not currently pulling water from either river.  The utility is able to meet current demand by relying on other water sources, including Maffitt Reservoir, Crystal lake and aquifer storage wells.  If demand increases, Des Moines Water Works will have no choice but to start taking water from the heavily polluted rivers, and may be unable to remove nitrate in a manner that keeps up with high demand.

“Although drought conditions are no longer an immediate threat to Central Iowa, increased nitrate levels from agricultural run-off, coupled with high demand, puts Des Moines Water Works in a difficult position,” Bill Stowe, CEO and General Manager, Des Moines Water Works. “With the assistance of all metro customers using water wisely, Des Moines Water Works can effectively and efficiently use the available water supply to provide safe drinking water that does not violate nitrate standards.”

Wise use of water is defined as identifying efficient lawn irrigation practices, taking advantage of technological advances to eliminate waste, as well as being alert to and repairing leaking household fixtures or other large water consumption appliances in homes and businesses.

Wise water best practices for residential and commercial irrigation use include:

  • Avoid lawn watering, whether from an in-ground sprinkler system or manual sprinkler, during the day time hours of 10:00 a.m. and 5:00 p.m.  Evaporation from the sun is highest during this time period and less water is absorbed into the soil, meaning more water must be used to get the same effect than if watering is done outside these hours.
  • Shift watering to no more frequently than the ODD numbered days of the week if your house address ends with an ODD number and EVEN numbered days if your house address ends with an EVEN number.  For example, if your house number is “1521,” it is suggested that you water on the 1st, 3rd, 5th, 7th, and so on days of the month.
  • Test the irrigation system each spring to ensure there are no leaking sprinkler heads and that each head is properly directing its spray onto the turf and landscape.
Posted by: Laura Sarcone No Comments
Labels: , , , , Posted in Conservation, Customer Service, Customers, Water Quality May 16, 2013

Customers Pay When Others Pollute

In response to Iowa Farm Bureau Federation’s environmental policy adviser, Rick Robinson’s “State Rules Wouldn’t Fix Nitrates” letter to The Des Moines Register on May 13.

Nitrate Removal FacilityThanks to a capital investment made years ago and the dedicated work of our employees Des Moines Water Works continues to meet the needs of the 500,000 customers in the twenty communities we serve. However, the extreme levels of nitrates found in our water supply this year poses a significant threat to our customers. We feel it is time for Iowans to engage in a serious discussion about this growing problem.

Nitrate levels in both the Raccoon and Des Moines Rivers exceeded the U.S. Environmental Protection Agency (EPA) nitrate standard (10 mg/l – determined as the level protective of public health) this spring. There were more nitrates in those rivers last week than there were all of last year combined.

Des Moines Water Works relies primarily on the Raccoon and Des Moines Rivers as sources for Central Iowa’s drinking water. Because unprecedented nitrate levels have affected both rivers concurrently, Des Moines Water Works activated its Nitrate Removal Facility last Friday to keep finished drinking water below EPA standards. This facility, constructed in 1992 for $3.6 million, costs $7,000 per day to operate. Ratepayers fund the cost of constructing, maintaining and operating this facility.

We agree with one thing Rick Robinson of Iowa Farm Bureau Federation wrote, “if we all do our part – farmers, homeowners, businesses and communities – we will have a positive impact on Iowa’s watershed.” Where we diverge is that we do not believe everyone is doing their part to protect Iowa’s waterways.

Des Moines Water Works had the foresight to build a denitrification facility. DMWW has not had to operate it since 2007, but this is largely because DMWW has invested millions of additional dollars in additional treatment options to provide denitrification since 2007. It is misleading for a person to suggest the denitrification facility’s lack of use during recent years is proof nitrate levels have been lower than they have been in past years. DMWW has been able to avoid the costly operation of the facility because of other actions and investments it has made.

The heart of Des Moines Water Works’ mission is protecting public health. We can no longer work quietly while source waters continue to be severely polluted by upstream land practices. This should not be a sterile discussion influenced only by data and statistics—although ample alarming data and statistics exist. Nitrates pose serious health risks. It is increasingly costly for Des Moines Water Works to remove nitrates through treatment processes to meet necessary EPA standards.

There is simply no disputing surface water is significantly impacted by certain types of land use – the primary land uses in our upstream watersheds are agricultural related. Chemical fertilizers applied to fields are exacerbated by field drainage tiles, allowing run off to reach rivers and streams quickly and without the benefit of natural filtration and, this year, plant uptake.

In addition to exceptional levels of nitrates, high levels of ammonia and phosphorus, algae blooms, and increasing levels of bacteria are all deteriorating water quality in Iowa. The recently published Nutrient Reduction Strategy supported by many prominent State leaders, including Iowa Department of Agriculture and Land StewardshipIowa Department of Natural Resources, and the Governor’s office, is inadequate in that it lacks regulation, goals, measurable outcomes, or timelines for reducing agricultural (non-point) discharges. We advocate regulation through EPA-endorsed numeric standards by watershed—an approach with local emphasis that considers the current state of each watershed and does not force a one-size-fits-all approach.

Facing the reality of the degrading water quality and open meaningful discussion to identify solutions is long overdue.

Iowans should demand state leaders address improving and protecting owa’s water sources. State funding to support monitoring of nitrate pollutants should not be stripped away from the flood center of Iowa, an objective guardian if Iowa’s rivers and streams. 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. With bold and innovative action, Des Moines Water Works believes healthy source waters and agriculture can co-exist. They must—both are critical to Iowa’s future.

Respectfully Submitted,

Water Works Board of Trustees:

Graham Gillette, Chair

David A. Carlson, Vice Chair

Leslie A. Gearhart, Trustee

Susan R. Huppert, Trustee

Marc R. Wallace, Trustee


William G. Stowe, Des Moines Water Works CEO & General Manager

Posted by: Laura Sarcone No Comments
Labels: , , , , Posted in Board of Trustees, Source Water, Water Quality February 25, 2011

Just the Facts – Nitrate in Drinking Water Q&A

Q. Is nitrate in drinking water a health concern?

Nitrate itself is generally not a concern with respect to human health. However, bacteria and other substances in the human body can transform nitrate from drinking water into nitrite, which can then be transformed into nitrosamines. Nitrosamines are compounds formed by the reaction between nitrite and secondary amines; they are also found in trace amounts in some processed fish and cured meats. Nitrite and nitrosamines have been shown to adversely affect human health. This is why the federal government regulates nitrate and nitrite levels in public drinking water supplies.

Blue-baby syndrome (methemoglobinemia) (rarely diagnosed in the U.S.) is caused by exposure to elevated levels of nitrite in infants less than 6 months old. Nitrite adversely affects the blood’s ability to carry oxygen, which can result in a bluish color in the infant’s skin. If not treated, blue-baby syndrome can be life threatening. Possible risk factors for blue-baby syndrome include nitrate in drinking water, some genetic conditions, and certain intestinal infections.

Research is ongoing on the possible association between exposure to nitrate in drinking water and the risk for certain cancers. In the body, the transformation of nitrate to nitrite to nitrosamines can occur; nitrosamines have been shown to be carcinogenic (cancer-causing) in laboratory animal studies. Conflicting results from studies on human exposure to nitrate in drinking water and risks for cancer have been reported in the scientific literature.

Q. How much nitrate in drinking water is safe?

The U.S. Environmental Protection Agency (EPA) regulates nitrate and nitrite based on concerns related to blue-baby syndrome. The maximum contaminant level (MCL) for public drinking water supplies is set at 10 mg/L** for nitrate nitrogen and the MCL for nitrite nitrogen in public drinking water supplies is set at 1 mg/L. Public water supplies cannot exceed these MCLs. Private well water is not regulated.

** 1 mg/L (milligram per liter) = 1part contaminant per million parts of water. One part per million is equivalent to a single penny in ten thousand dollars.

Q. Is water the only source of nitrate to which humans are exposed?

No. Nitrate also occurs naturally in the environment, is found in many vegetables and some processed meats, and is produced naturally within the human body. Nitrate from drinking water accounts for between 15% – 75% of a person’s exposure to nitrate from environmental sources. The higher the nitrate nitrogen level in water, the greater the overall contribution. In addition, many vegetables and fruits contain substances (such as vitamins C and E) that inhibit the transformation of nitrate nitrogen to nitrite to nitrosamines. This “protective factor” may lessen the contribution of nitrate from vegetables that is  vailable for conversion to nitrite in the digestive system.

Q. What can I do about nitrate in my drinking water?

Nitrate levels in municipal and other public water supplies are required to be within federal standards. This includes regular monitoring and testing drinking water supplies. If you have a private well, you should have your water tested on a regular basis (every one- two years). Boiling water increases the nitrate concentrations. Certain types of in-home treatment systems will remove nitrate, but they must be maintained regularly to protect public health. If you have health concerns about nitrate in your water, talk to your doctor. For information on public programs, contact your local health department or your county sanitarian. There are state funded programs for evaluating the susceptibility of private wells to contamination (Farm*A*Syst) and for private well water testing (Grants to Counties). Information can be found on the web at (on this site select publications) and where you can find facts sheets on drinking water quality and water quality programs.

For more information, call Des Moines Water Works at (515) 283-8700 or visit

Developed in consultation with Agribusiness Association of Iowa, Cedar Rapids Water Department, Center for Health Effects of Environmental Contamination-University of Iowa, Des Moines Water Works, Iowa Association of Water Agencies, Iowa Corn Growers Association, Iowa Soybean Association, Iowa State  niversity Extension, and U.S. Dept. of Agriculture-National Soil Tilth Laboratory.

Want more Just the Facts? Visit:

Posted by: Laura Sarcone No Comments
Labels: , , , , , Posted in Health, Water Quality, Water Treatment