In Iowa and nationwide, algae problem ‘definitely growing’

Big Creek Lake was one of several Iowa lakes where public advisories concerning algae blooms were issued this summer.

As hot, dry conditions and low water levels persisted across Iowa this summer and turned vegetation across the state dry and brown, you might have noticed an unusual amount of green in Iowa’s rivers and lakes.

That’s because conditions were right in Iowa this summer to support large amounts of algae growth in our waterways, which often appears as green scum lining the edge of a river or lake.

At best, the algae is a nuisance, making wading or swimming in the water less attractive.  At worst, algae blooms can threaten the health of people and animals.

Blue-green algae, known as cyanobacteria, can release toxins that cause allergic reactions, skin, eye or throat irritation, or breathing difficulties, according to a fact sheet on blue-green algae prepared by the Iowa Department of Public Health.

Across the country, the problem of blue-green algae is “definitely growing,” according to Jeffrey Reutter, director of the Stone Laboratory at The Ohio State University, who was quoted by the Center for Investigative Reporting.

“The blooms occur in nearly every state, peaking in August and September. And although no national agency tracks the blooms, experts say they are getting worse, driven by fertilizer and manure runoff into lakes and streams combined with a warming climate,” wrote reporter Jessica Marshall.

Reducing runoff pollution in Iowa’s waters—sometimes called “non-point source pollution”—is the Iowa Environmental Council’s top clean water priority.

a widespread pollution problem

Solving this problem will take a lot of work.  The scope of America’s algae problem is large enough that NASA’s Landsat-5 satellite can see it from space.  In the image below, taken about one year ago on October 5, 2011, a large algae bloom is clearly visible in Lake Erie.

Landsat image created for NASA’s Earth Observatory by Jesse Allen and Robert Simmon, using data provided courtesy of the United States Geological Survey.

According to NASA, “The green scum shown in this image is the worst algae bloom Lake Erie has experienced in decades. Such blooms were common in the lake’s shallow western basin in the 1950s and 60s. Phosphorus from farms, sewage, and industry fertilized the waters so that huge algae blooms developed year after year. The blooms subsided a bit starting in the 1970s, when regulations and improvements in agriculture and sewage treatment limited the amount of phosphorus that reached the lake.”

But last year, a wet spring swept a wide array of pollutants—including phosphorus, a common fertilizer—into the lake, and the algae returned.  Invasive zebra mussels may have also played a role in Lake Erie.

The U.S. Environmental Protection Agency has called nitrogen and phosphorus pollution “one of America’s most widespread, costly, and challenging environmental problems.”  The agency is working with states, including Iowa, to reduce levels of nitrogen and phosphorus in rivers, lakes, and streams.

Above:  An EPA produced video explains the nature of the nutrient pollution problem.

a need for urgency

But progress to address the problem has been slow.  That’s why, this March, the Iowa Environmental Council joined other environmental groups up and down the Mississippi River in a pair of legal actions intended to compel the EPA to take a stronger stance on this pollution problem.

Partnership among states in the Mississippi River Basin is critical, because combined, the 31 states in the basin send excess nutrients down the Mississippi River that creates the so-called “Dead Zone,” an area in the Gulf of Mexico largely devoid of life.

In March, Susan Heathcote, the Iowa Environmental Council’s water program director, criticized the pace of EPA’s efforts to work with states to establish pollution limits for nitrogen and phosphorus in waterways.

“EPA isn’t exercising its authority to ensure states put standards in place, and meanwhile, Iowa has backed away from its own efforts to do so.  Even though EPA has repeatedly said how important these pollution limits are, the agency’s current strategy is failing to meet the goals of the Clean Water Act,” Heathcote said.

The Iowa Environmental Council will continue its efforts to work with cities and towns, farmers and landowners, and all Iowans to reduce nitrogen and phosphorus pollution that is keeping Iowa’s waters brown and green, not clear and clean.

Meanwhile, if an algae bloom interfered with your enjoyment of Iowa’s rivers and lakes this summer, feel free to share your story in the comments below.


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