Published March 24, 2006
Rivers in Iowa among the nation's most highly polluted
REGISTER STAFF WRITER
Look at a map of the nation's water-pollution hot spots, and a state in the middle stands out.
It's no secret the state has water-quality problems. But a new analysis by The Des Moines Register shows the state ranks among the nation's highest in fecal bacteria, nitrogen and phosphorus pollution. And those aren't the only problems.
Those pollutants leave the state's rivers with fewer fish, worse stink and more health-threatening organisms than they would have without the contaminants flowing in. Iowans must pay more to clean the water headed for their taps and the sewage headed for their rivers. Fewer people canoe or fish than might if the waters were more appealing.
The state has enacted new rules to clamp down on sewage pollution, while the Iowa Department of Natural Resources looks for ways to cut the runoff pollution that is an even bigger problem. The rules will force improvements at some sewage-treatment plants. In some towns, monthly bills could go up as much as $40.
The debate over Iowa's failure to comply with the 1972 Clean Water Act prompted a key question: Are Iowa's waters worse off than those in other states? It's a complicated question that defies an easy answer. States often don't test their water the same way, and environmental conditions vary with geology and other factors.
By many measures, though, the answer is yes. Research spanning decades shows that Iowa has some of the nation's most serious water-quality challenges.
Some of the statistics show Iowa's waters are even more troubled than those in bordering states that also are major grain producers.
In the Corn Belt, Iowa ranks at the top in fertilizer pollution. Iowa streams' concentrations of nitrogen and phosphorus - fertilizer ingredients that speed the natural death of rivers and lakes - are among the highest in the world, according to an Iowa State University study.
Des Moines installed one of the largest nitrate-removal plants in the world. For good reason: The health-threatening compounds caused, in part, by crop fertilizers register in some Iowa streams at levels 50 percent higher than in the rest of the Corn Belt, and 18 times the U.S. median.
In some tributaries of the Raccoon River, the main water source for 300,000 people, nitrates are found at levels several times the drinking-water limit.
"Something has to change," said L.D. McMullen, general manager of Des Moines Water Works.
Look at a U.S. Geological Survey map of the origins of the nitrogen that causes a summertime "dead zone" in Louisiana's lucrative shrimping grounds, and there are two states that clearly are the biggest sources. Iowa and its corn-growing sister, Illinois, account for up to 35 percent of the nitrogen washing down the Mississippi River watershed, which covers 41 percent of the lower 48 states.
The fertilizer feeds huge algae blooms in the Gulf. When the algae die, the decomposition leaves deep water without oxygen, killing plants and fish that don't move on to better waters.
The Iowa Department of Natural Resources is pushing for change. The state plans to set new sewage limits with the new rules. The department also is looking for ways to cut the runoff that accounts for 90 percent of the pollution in streams.
Runoff, especially with fertilizer, leaves Iowa's waters green, fighting for oxygen and with fewer fish than they would contain naturally. That could cripple a fishing industry that accounts for $336 million in spending a year, which already is far lower than in many other states.
Many farmers use less fertilizer than they used to, and Iowa leads the nation in the installation of grassy buffer strips. Yet farmers each year lay miles of new drainage pipes. That turns their fields into the equivalent of sink drains that flush pollutants toward streams before they can be soaked up by wetlands or buffer strips.
Swim in phosphorus
The U.S. Geological Survey in the late 1990s discovered that the average phosphorus level in some Iowa streams was triple the U.S. average and 14 percent higher than average levels in the other corn-growing states.
A U.S. Environmental Protection Agency report on pollution in small streams in Iowa, Kansas, Missouri and Nebraska from 1999 to 2001 showed that those in Iowa posted the top 53 of 675 nitrate readings and the top 44 nitrogen readings. Nebraska fared worse on phosphorus, with five of the top 10 readings; Iowa had two.
Nitrogen and phosphorus feed algae blooms that suck oxygen from lakes and rivers.
Other runoff ingredients are big issues, too, studies show.
Pesticides are found in groundwater across the state, as is the case in many agricultural areas. The levels are below federal health standards, although scientists don't really know what happens when we drink small amounts of several pesticides - a common occurrence in Iowa.
Iowa's waters are cloudier than many others, hampering fish populations and encouraging the growth of pathogens that could make people sick.
Fecal bacterial levels run many times the level considered safe for human contact in some rivers. That means waders, swimmers, fishing enthusiasts, kayakers, boaters, tubers and rafters all are at a bit more risk of getting diarrhea, a skin infection or worse by getting the water in their mouths or in open wounds.
A volunteer's view
Kristie Reck spent a glorious day last year letting her kids splash in the Rocklyn Park creek in the Des Moines suburb of Urbandale. While she was there, she pulled water samples as a volunteer in a statewide network.
Fortunately, she had her kids use antibacterial wipes to clean their hands, so the children weren't at risk of intestinal illness or infections that can come from organisms in the water.
Later, Reck got the test results. The water was carrying fecal bacteria levels that were more than 50 times what is considered safe for human contact.
She has also noticed that Walnut Creek, near her home in suburban Des Moines, smells foul after rains.
Reck said she's seen and smelled worse, including waters polluted by Superfund sites near Washington, D.C. But she's seen better, including the rivers of South Dakota, which has sold its streams and lakes as destinations for tourists.
"In Iowa, water is seen more as a resource to be used up and used as dump for agriculture," said Reck, 37, a native Iowan who lived in several other states. "The attitude in South Dakota is the waters are beautiful and accessible and you can see through the water, and there is no odor."
Rocklyn and Walnut creeks are among many that Iowa environmental authorities target for cleanup.
A fisherman's view
Ryan Maas, a fly fisherman from Iowa City, likes to fish and swim in the Wisconsin River upstream from the Mississippi River. He's noticed that the water is clearer than in many Iowa streams, and more protected by buffer strips and other soil-conservation practices.
"When we canoe the Wisconsin, we get out and swim, we fish. It's more inviting to do that in that sort of water body that's clean, clear, than in some of the Iowa streams where you have significant erosion going on, where you have runoff, where you have fertilizers, pesticides and bacteria."
Bacteria levels in streams vary widely with rainfall and land use. However, Iowa data show the state's rivers routinely carry high levels of fecal bacteria. That means it is likely organisms that can make people sick are there, too.
For example, the Raccoon River - popular with canoeists and kayakers and a chief source of Des Moines-area drinking water - routinely has higher readings in summer than New Orleans did after Hurricane Katrina hit. More bacteria means higher costs for treatment, and at least a small chance that fun-seekers will get sick.
Since 1997, the average levels of fecal bacteria in the Raccoon River have been double to seven times the standard for human contact. The Des Moines Water Works reported in April 2005 that the Raccoon River at Fleur Drive, near the water-treatment plant, had never met the swimming standard in eight years of testing. Fewer Iowans swim in rivers than in lakes, but tubing, kayaking, canoeing, wading and fishing also expose recreationalists to pathogens.
The streams that feed the Raccoon also carry bacteria at levels that suggest health risks, according to state and federal standards.
One stretch of Brushy Creek near Dedham on April 12 carried bacteria concentrations 4,765 times the swimming standard. Last year, Walnut Creek and the North, Middle and South Raccoon branches had fecal bacteria averages that ranged from under the swimming limit to 866 times the safe level.
Water treatment kills the bacteria before the water reaches taps. But for people who fish, swim, wade, canoe or kayak, those levels mean at least a small risk of illness. For those with suppressed immune systems, the risk can be far greater. That same stretch posted its lowest reading on July 7 - and still was five times the limit.
Tributaries of the Raccoon River near Pomeroy last year recorded fecal bacteria levels 10 times the level considered safe for humans to touch.
The level of bacteria in other states varies. Louisville, Ky., and Cincinnati, Ohio, get drinking water from the Ohio River. Bacteria levels were 39 times the swimming limit at Cincinnati, and as much as 27 times the limit at Louisville.
The streams running into Blue Marsh Lake in Berks County, Pa., met the swimming limit in the fall of 2001 - when bacteria levels begin to drop off as water cools - but ran five times the limit after rainfalls, a U.S. Geological Survey study found. A late-1990s study of Indian Creek in agricultural North Carolina found levels of up to 54 times the contact limit. Cow Castle Creek, S.C., posted readings 40 times the contact limit test.
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