Scientists predict the 2019 Gulf of Mexico “dead zone” to be one the largest


Gulf of Mexico. Photo by eutrophication&hypoxia, Flickr.

By Julia Shanahan | July 12th, 2019

The 2019 Gulf of Mexico “dead zone” will be the second-largest recorded, scientists from Louisiana State University announced this week.

The “dead zone” – an oxygen-depleted area of water in the Gulf of Mexico caused by nitrogen and phosphorus – will cover 8,717 square-miles as of this summer. Unusually high river discharge from the Mississippi River in May contributed to the growth of the dead zone. Oxygen depletion, or hypoxia, also threatens marine life, including fish, shrimp, and crabs.

The National Oceanic and Atmospheric Administration also predicted the dead zone to reach record-highs. In 2017, the dead zone reached about 8,776 square-feet, as reported by the NOAA.  LSU scientists predict the 2019 hypoxic area to be about the size of New Hampshire.

The NOAA also attributed the growth in the annual dead zone to the record rainfall and flooding that happened in the spring months. The U.S. Geological Survey estimated a total of 156,000 metric tons of nitrate and 25,300 metric tons of phosphorus were carried from the Mississippi River and into the Gulf of Mexico in May alone.

Iowa experienced record flooding from the Missouri River in the spring, which contributed to the nutrient runoff in the Mississippi River. Iowa remains a major contributor to the annual Gulf of Mexico dead zone.

Low oxygen levels appeared about 50 years ago when farming intensified in the Midwest, according to the press release from LSU. In the last few decades, there has not been a reduction in the amount of nitrogen and phosphorus from the Mississippi into the Gulf of Mexico. 

Nitrate levels in drinking water linked to increase risks for cancers


Photo by Pixabay on Pexels.com

By Julia Shanahan | June 20th, 2019

The Environmental Working Group released a study outlining a link between the amount of nitrates someone consumes through tap water to a higher risk of cancer. Nitrate pollution in U.S. drinking water potentially caused 12,594 cases of cancer in a year, according to the study.

The study attributed the large amount of nitrates in drinking water to agricultural runoff that contains fertilizer and manure. The EWG estimates it would cost about $1.5 billion a year in medical costs to treat those cases. Of those 12,594 cases, 54-82 percent are colorectal cancer cases. Additionally, the risk for bladder and ovarian cancers are increased in postmenapausal women.   

The current federal limit for the amount of nitrates legally allowed in drinking water is 10 parts per million, but as outlined in the study, other serious health risks have been linked to nitrate-polluted water that is only one-tenth under the federal limit. Scientists from the EWG estimate that in order for there to be no adverse health risks, the nitrate level in drinking water should be 0.14 milligrams, which is 70 times lower than the EPA’s legal limit.

In Iowa, nitrate pollution remains a threat to tap water and well water in rural and urban cities across the farm state. The Iowa Department of Public Health tested 1,700 private wells and found 19 percent of them were at or above the legal limit for nitrates. In 2014 and 2015, the average nitrate levels in 45 Iowa public water systems were at least 5 milligrams – enough to increase someone’s risk of cancer.

More recently in 2018, the Des Moines River and combined Cedar-Iowa Rivers produced the nitrate equivalent of 56 million people. The total amount of nitrates in Iowa rivers in 2018 was 626 million pounds, and treated in sewer discharge amounted to 123 million people, or as blogger and IIHR Research Engineer Chris Jones compares to the population of Japan.

On The Radio- West Nile virus in Iowa


34301252464_7c3440cfb3_o.jpg
(flickr/cesar monico)

Kasey Dresser| June 17, 2019

This week’s segment looks at the unwanted guest brought into Iowa by the rain and flooding this season. 

Transcript: 

The West Nile virus may soon run rampant because of the flooding that has been occurring in western Iowa.

This is the Iowa Environmental Focus.

Mosquitoes are not abnormal residents in the western region of Iowa. Yet these types of mosquitoes, the Culex tarsalis (Cool-ex tar-say-lis)  is carrying a virus that could hurt human beings.

The Culex tarsalis, have risen in grand numbers because they gather and breed in large pools of water and flooded areas. Iowa State University came out with new research that shows western Iowa has the largest presence of the West Nile virus, due to the resurgence of these mosquitoes.   

Iowa State professor and entomologist Ryan Smith believes that the virus is concerning as it is the common mosquito-born disease in the United States. The virus could affect one in five people bitten by the mosquito, and could lead people to develop fevers and potentially fatal symptoms.

The best way to protect yourself, would be to consistently spray insect repellent or wear long sleeve shirts. Make sure that you are fully covered before stepping outside.

For more information, visit Iowa environmental focus dot org.

From the UI Center for Global and Regional Environmental Research, I’m Sara E. Mason.

 

On The Radio- Decreasing fish populations


5321957538_f476d2560a_o.jpg
(flickr/nanarab)

Kasey Dresser| May 20, 2019

This weeks segment looks at how fish populations are decreasing as ocean temperatures continue to increase. 

Transcript: 

Overfishing is not the only factor decreasing fish populations.

This is the Iowa Environmental Focus.

A study published in the journal, Science, tracked the changes of 235 fish and shellfish populations from 1930 to 2010. Throughout that time, the Earth’s ocean temperatures have increased on average by half a degree Celcius.

Eight percent of the fish and shellfish in the study showed depleting populations. Four percent of the populations increased however, since fish like black sea bass thrive in warm water. As water temperatures continue to increase, those gains will not be sustained.

Christopher Free, a quantitative ecologist at the University of California Santa Barbara, referred to this trend as the fish and shellfish reaching their heat thresholds. Currently,124 species of fish and shellfish are on route to becoming an unstable food source.

3.2 billion people worldwide rely on seafood as their primary source of protein. These findings are meant to inform local fisheries of the changing populations so they can begin to take these findings into account.

For more information, visit Iowa environmental focus dot org.

From the UI Center for Global and Regional Environmental Research, I’m Sara E. Mason.

 

Northeast Iowa streams, springs and wells test positive for disease-causing microbes


16578744517_ed4293d3e7_z.jpg
E. coli bacteria, which was found in its pathogenic form in northeast Iowa waters (flickr).

Julia Poska| May 3, 2019

Luther College biologists have found disease-causing bacteria and parasites in Winneshiek County water, in some cases at disease-causing concentrations, according to Iowa Public Radio.

Over half of the 48 surface water samples Jodi Enos-Berlage and Eric Baack took at streams and springs tested positive for cryptosporidium, a parasitic protist that can cause digestive distress for weeks. Half of the 22 private wells tested showed cryptosporidium, too, but at significantly lower levels, the researchers said.

Twenty percent of the surface waters tested positive for the Shiga toxin, as well, which is produced by the pathogenic strain of E. coli. At some sites, the concentration of the toxin in just one cup of water would be high enough to cause fever and digestive distress if consumed.

The biologists also tested for indicators of human and animal feces, which could have carried those pathogens into the water via farm runoff or aging septic systems. Baack told IPR he was surprised to find low-level  fecal contamination widespread in surface waters.  The researchers found less fecal contamination in wells.

 

 

 

Disastrous forecast realized in Davenport flood


5677131116_0f67935e02_b.jpg
Davenport flooding in 2011 (flickr).

Julia Poska|May 2, 2019

The Quad Cities have been preparing since the National Weather Service reported earlier this year a 95 percent chance of pronounced flooding in the area through May. As of Tuesday, their temporary barriers had been in place for 48 days. This week, their preparations proved insufficient.

Tuesday afternoon, Mississippi River floodwaters suddenly rushed into Davenport when HESCO Barriers — military grade defense boxes used to make temporary walls — succumbed to the force of the water. Officials saw early signs, the Quad City Times and Dispatch-Argus reported, and began urging people in some areas to evacuate when the temporary levees began breaking around 3:30 pm. The HESCO barriers had never been tested in waters above 21.5 feet, but as of 4:30 pm the Mississippi was at 21.87 feet, heading quickly to the expected 22.4 foot crest.

Not everyone received or took seriously the evacuation warnings, and many had to be rescued by boat after the fact. Once the water came rushing in, there was little time to take action. No serious injuries were reported.

The Weather Channel reported that floodwater began to recede Wednesday morning, and that at their peak levels surpassed 6 feet in some areas. A new expected crest of 22.7 feet is expected later today, which could surpass the 22.6 foot record set in 1993.

Scott County officials and Gov. Kim Reynolds are hoping President Trump’s earlier disaster declaration for western Iowa will extend into the Quad Cities area, local media reported.

 

 

On The Radio- Preparing for flood season


2629707266_af3f219dbf_o.jpg
Photo from the 2008 June floods (christina rutz/flickr)

Kasey Dresser| April 29, 2019

This weeks segment looks at how towns along the Mississippi are preparing for flood season. 

Transcript: 

As flood season begins, mayors of towns along the Mississippi prepare for potential disaster. 

This is the Iowa Environmental Focus. 

It’s not easy maintaining a city or town along the Mississippi. The river—one of the largest in the world—is especially susceptible to floods during spring, when rain and melting snow cause the water levels to rise significantly.

The Mississippi River Cities and Towns Initiative is a collection of 88 mayors spanning 10 states that work together to find solutions for flooding. They’ve been setting safety measures in place for this coming flood season, one that’s predicted to be especially disastrous.  

In late March, the group talked with the Federal Emergency Management Agency to figure out some preventative measures. Previously, they gathered in Washington DC to work out a nearly eight billion dollar deal to help reinforce existing infrastructure. Midwestern states have sustained billions in flood damages just this year, and supposedly once-in-a-lifetime floods have hit St. Louis on three different occasions since 2011.

These previously rare weather events have been happening more and more frequently, and the coalition is amping up their defenses to beat back the oncoming waves. 

For more information, visit Iowa Environmental Focus dot org. 

From the UI Center for Global and Regional Environmental Research, I’m Sara E Mason.