Climate change likely to cause surge in nutrient runoff


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A small portion of a hypoxic dead zone in the Chesapeake Bay. (Chesapeake Bay Program)
Jenna Ladd| August 4, 2017

A recent study found that increased precipitation due to climate change will lead to markedly increased nutrient runoff.

Nitrogen rich fertilizers are widely used by U.S. farmers. Many times, more fertilizer than crops can use are applied to the land and the excess runs off into local waterways, eventually draining into the ocean. Excessive nutrient enrichment, also known as eutrophication, decreases available oxygen in the water and kills off aquatic species, resulting in “dead zones.”

Warmer temperatures associated with climate change are expected to continue producing heavier rainfall, thereby increasing nutrient runoff by up to twenty percent by 2100. Anna Michalak, a professor of global ecology at the Carnegie Institution for Science at Stanford and one of the authors of the study, told the New York Times, “When we think about climate change, we are used to thinking about water quantity — drought, flooding, extreme rainfall and things along those lines. Climate change is just as tightly linked to issues related to water quality, and it’s not enough for the water to just be there, it has to be sustainable.”

Researchers concluded that the Upper Mississippi Atchafalaya River Basin, the Northeast and the Great Lakes basin are likely to see the largest increases in nutrient runoff because these areas of the country are already creating hypoxic dead zones. Climate change will likely compound these effects.

While the study focused on the continental U.S., the researchers did apply their model to parts of the world most similar to it. They found that large areas of East, South and Southeast Asia will likely see nutrient runoff surges similar to those in the U.S. Given that some people in these regions depend on surface water to survive, the impacts of nutrient pollution there may be especially lethal.

Report provides inventory of water monitoring efforts in Iowa


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Constructing wetlands is a proven practice that helps to reduce nutrient runoff from agricultural land. (USDA/flickr)
Jenna Ladd | December 23, 2016

A 2016 report from the Iowa Department of Natural Resources in partnership with the Iowa Department of Agriculture and Land Stewardship summarizes Iowa’s water quality monitoring efforts.

The report, which was also supported by Iowa State University and the University of Iowa IIHR—Hydroscience and Engineering Center, provides a complete list of all nutrient-specific water monitoring sites in the state. The first of its kind, it was developed to inform the Iowa Nutrient Reduction Strategy. The Iowa Nutrient Reduction Strategy aims to monitor and reduce nutrients delivered to Iowa waterways and subsequently to the Gulf of Mexico by 45 percent.

Iowa Secretary of Agriculture Bill Northey said,

“Iowa has a comprehensive water quality monitoring effort in place that is supported by a variety of partners. Monitoring results were central to identifying the practices highlighted in the Iowa Nutrient Reduction Strategy and have provided valuable information as we have established priority watersheds. It continues to be an important part of our efforts as we work to increase the pace and scale of practice adoption needed to improve water quality.”

The report outlined all water monitoring efforts according their type and scale:

  • Edge-of-field monitoring
    • Researchers partner with farmers to monitor water quality on the edge of farm fields in order to accurately prioritize nutrient reduction practices.
  • Paired watershed monitoring
    • These are sites wherein the effectiveness of conservation practices are tested on two similar watersheds, one watershed receives intentional conservation measures and the other does not.
  • Large watershed monitoring (950,000 total acres)
    • These sites are either part of University of Iowa’s IIHR – Hydroscience and Engineering management of 45 real-time management stations or Iowa DNR’s 60 statewide sites.
  • Small watershed monitoring (22,500 total acres)
    • Several small watershed monitoring projects are ongoing including 18 established by the Iowa Water Quality Initiative. Many of these projects measure the effectiveness of conservation practices implemented by farmers.

The report also detailed the many challenges associated with nutrient-specific water quality monitoring. Complicating factors can include frequently changing land-use, varying streamflow and precipitation, and a lack of long-term monitoring records.

Iowa DNR director Chuck Gipp said, “While challenges exist, we believe continued nutrient monitoring is critical to understanding what Iowa can do to be successful.” He added, “All partners involved in developing this report know the value of long-term evaluation and are committed to continuing with a science-based approach to nutrient reduction in Iowa waters.”

Researchers call for EPA enforcement of nutrient-reduction plans


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The hypoxic dead zone in the Gulf of Mexico has not decreased in size since Iowa’s Nutrient Reduction Plan was established in 2013. (NOAA)
Jenna Ladd | November 18, 2016

A November report by the Iowa Policy Project evaluates the state’s nutrient reduction progress since its Nutrient Reduction Plan (NRS) was released in 2013.

The report states that despite Iowa’s voluntary nutrient reduction plan, recent data from the National Oceanic and Atmospheric Administration (NOAA) and United States Geological Survey (USGS) indicates that the size of the hypoxic “dead zone” in the Gulf of Mexico has shown no improvement. Iowa Policy Project, an Iowa City-based research group, also posits that the latest annual report from NRS overstates progress that has been made in the state. The NRS report notes that some producers have implemented conservation land-use practices such as cover crops and buffer zones, but doesn’t emphasize that others have failed to maintain or eliminated conservation areas. Among other criticisms, IPP points out that while the Iowa acres in cover crop did increase by 125,000 acres from 2014 to 2015, these improvements must be considered in context. There are a total of 400,000 acres currently in cover crop, but this only represents less than 2 percent of Iowa’s 24 million acres of row crop land.

Many of the conservation efforts are voluntary for farmers in Iowa. IPP reports that more than 40 percent of farmers spent less than $500 a year in conservation practices in the ten year period prior to a 2014 Farm and Rural Life Poll by Iowa State University. Another report released by the Mississippi River Collaborative in November said that the Environmental Protection Agency (EPA) has failed to establish “enforceable regulations, specific deadlines or funding” to help Iowa and other agricultural states mitigate their nutrient pollution. Kris Sigford, water quality director at the Minnesota Center for Environmental Advocacy and member of the Mississippi River Collaborative said, “The results of the EPA’s hands-off approach with the Mississippi River basin states are massive algae blooms and nitrate contamination that make our drinking water unsafe and render lakes and rivers unfit for recreation.” EPA responded with a statement on Thursday  stating that the agency has “called upon states and stakeholders to intensify their efforts” to address the issue, one of America’s “most widespread and costly environmental and public health challenges.” They added, however, that they “cannot solve nutrient pollution by top-down federal action.”

EPA’s comments follow a record-breaking summer of Iowa beach closures due to toxic algae blooms. The Mississippi River Collaborative, which has sued EPA for its lack of enforcement, and other environmental groups call the federal agency to set limits on nutrient pollution for states, improve nutrient assessment and water-quality monitoring for Iowa’s waterways and to clearly establish goals and funding for nutrient-reduction initiatives. The collaborative also supports a sales tax increase of three-eighths of one cent to fund water quality projects through the Natural Resources and Outdoor Recreation Trust Fund. Susan Heathcote, the Iowa Environmental Council’s water program director, points out that if the sales tax revenue is established, “we need to pair that with good accountability measures so we can tell the taxpayers that these dollars are being invested wisely — that we have a plan.”

Nitrates often released back into rivers


Photo via Jason Mrachina; Flickr
Des Moines cityscape. Photo via Jason Mrachina; Flickr

According to the Des Moines Register, Des Moines’ nitrate removal facility was responsible for dumping approximately 13,500 pounds of the contaminant into the Raccoon River last year.

Nitrates can be detrimental to human health if consumed in high enough quantities, which is why the U.S. Environmental Protection Agency requires drinking water to be monitored for the compound. However, once nitrates are removed from the drinking water, they are often released back into Iowa’s waterways.

The Des Moines location is not alone in this practice. The majority of Iowa’s other 15 nitrate removal facilities follow the same routine, and many do not monitor what quantity of nitrate they are releasing.

Although this practice is completely legal, it has serious environmental ramifications. The Raccoon River is part of the Mississippi River watershed, which empties into the Gulf of Mexico. Midwest fertilizer runoff from the watershed, high in nitrates, is largely responsible for the Gulf of Mexico’s Dead Zone. Nitrate levels in the Gulf’s water allow algal blooms to thrive, which in turn leads to low oxygen levels that are deadly for many aquatic species.

The future is not completely bleak; progress is being made towards preventing the nitrates from reaching water systems in the first place. Farmers and researchers are collaborating to explore and advance environmentally sustainable agricultural practices.

On the Radio: Freshwater Clam Research


Photo by user tlindenbaum; Flickr

This week’s On the Radio segment covers research being done at the University of Iowa that looks into the relationship between freshwater clams and excess nitrogen in rivers. Listen to the audio below, or continue reading for the transcript.

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On the Radio: Iowa water quality monitoring contract


Photo by Joe Wolf; Flickr

This week’s On the Radio segment covers the state’s contract with Iowa State University to monitor water quality in Iowa lakes. Listen to the audio below, or continue reading for the transcript. 

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Iowa farm runoff one of the major causes of an oxygen-depleted dead zone


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Photo by USDAgov; Flickr

A recent study on the Gulf of Mexico’s oxygen levels shows that this year’s dead zone will be the biggest since 1985 and Iowa is a big part of it. Continue reading