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Why are algal bloom problems growing?

August 13th, 2014 by

The recent contamination of drinking water in Toledo, Ohio brought the risks of algal blooms center stage and raised serious concerns for the future. Questions on everybody’s mind are what are toxic algal blooms, what causes them, and what can we do? Michael Brennan, IISG’s water quality outreach specialist, has some answers:

 
Regional scientists have been concerned about algal blooms like the one we saw a few weeks ago for some time. Its unique conditions make western Lake Erie particularly susceptible to algae blooms, both toxic and non-toxic. Warm temperatures, shallow, slow-moving water, and excessive nitrogen and phosphorus concentrations create optimal conditions for algae to thrive during summer months. 
 
Let’s step back a bit. Algal blooms are essentially overgrowths of algae triggered by excess concentrations of nitrogen and phosphorus carried in stormwater runoff from lawns, leaky septic systems, golf courses, and agricultural fields to nearby waterbodies. The severity of a seasonal algal bloom is directly related to annual rainfall accumulation and the number of severe rainfall events
 
Non-toxic blooms occur all over the Great Lakes. Occasionally, the algae associated with blooms—a cyanobacteria—releases a toxin known as microcystin. This is the toxin responsible for contaminating the drinking water of over 500,000 people in the Toledo area.
 
But even non-toxic algal blooms are harmful. When rapid algal growth dies off, decomposition sucks oxygen out of the water, depriving freshwater organisms of the oxygen needed to survive. Decomposition also slowly releases nitrogen and phosphorus back to the water column, setting the stage for the cycle to start again next season.
 
There are no quick fixes in Lake Erie or any of the other lakes. But there are things we can do. Better stormwater management through green infrastructure  is key. Unlike impervious surfaces, the plants and trees used in green infrastructure can absorb water and filter out pollutants before it reaches a waterbody. 
 
Individuals can help prevent algal blooms as well. Homeowners and gardeners can adopt natural lawn and landscaping practices that conserve water and reduce stormwater runoff. Most of these practices are simple and cost-effective, like applying nitrogen fertilizer only in fall, removing weeds by pulling and hoeing, and limiting watering to the mornings and evenings.  
For more information on what you can do please see the Environmental Protection Agency nutrient pollution page.
 
**Photo courtesy of Ohio Department of Natural Resources 

In the news: Cause of Lake Erie’s algae becoming clearer

April 16th, 2014 by
Lake Erie is one of the Great Lakes that is most affected by toxic algal blooms, and finding the cause for them is the first step in reducing or preventing them. Scientists may be closer to understanding just what causes these harmful blooms. 
 
“Algal blooms and dead zones in Lake Erie were severe during the 1960s, caused primarily by large releases of phosphorus from sewage and industrial plants. The 1972 federal Clean Water Act and the 1978 bi-national Great Lakes Water Quality Agreement led to dramatic reductions in phosphorus from these sources and a rapid improvement in water quality.
 
Lake Erie, however, saw a reemergence of the algal blooms and the growth of the dead zone in the mid-1990s, and the problems are worsening. In 2011, for example, Lake Erie experienced its most severe bloom of toxic algae on record. Last fall a toxic algal bloom in the lake forced officials to shut off a public water supply system in Ohio.
 
The new studies, part of the Ecological Forecasting (EcoFore) Lake Erie project led by researchers at the University of Michigan, found that the current targets to reduce phosphorus to alleviate algal blooms in Lake Erie may not be low enough to revive the dead zone. That conclusion informed the International Joint Commission’s recommendations in February for improving Lake Erie’s water quality.
 
The findings, and those of other studies from across the Great Lakes region, are delivering an ever clearer picture of the specific causes of nonpoint phosphorus runoff, algal blooms, and dead zones. The basic drivers of these problems are no longer unknown. The new research fills a critical void in information that has been often cited as a reason that strict regulations on nonpoint pollution sources, including agriculture, were not regulated under the 1972 federal Clean Water Act.”
Read the complete article and findings at the link above.

Lake Erie “dead zone” research includes work by IISG specialist

March 3rd, 2014 by
Illinois-Indiana Sea Grant’s Tomas Höök, associate director for research, was part of a team of researchers involved in a comprehensive study on Lake Erie’s health and measures needed to protect it.
 
From Phys.org
“The report from the multi-institution EcoFore-Lake Erie project states that a 46 percent reduction in the amount, or load, of phosphorus pollution would be needed to shrink Lake Erie’s Central Basin hypoxic zone to a size last seen in the mid-1990s—a time that coincided with the recovery of several recreational and commercial fisheries in the lake’s west and central basins.
 
Phosphorus is a nutrient used in crop fertilizers. Excess phosphorus washes off croplands during rainstorms and flows downstream in rivers that feed the Great Lakes. Once in the lakes, phosphorus can trigger algae blooms. When the algae die and sink to the lake bottom, oxygen-consuming bacteria feed on them and create hypoxic zones in the process. Many fish shun these oxygen-starved waters, which significantly reduce the amount of suitable habitat available to the fish.
 
The study, accepted for publication in a forthcoming edition of the Journal of Great Lakes Research, calls for Central Basin phosphorus reductions considerably higher than other recent recommendations, including a proposal issued last year by the Ohio Lake Erie Phosphorus Task Force aimed at avoiding Western Basin toxic algae blooms. The new report is a synthesis of the major findings from the EcoFore-Lake Erie project, created in 2005 and supported by the U.S. National Oceanic and Atmospheric Administration’s Center for Sponsored Coastal Ocean Research.”
Read the rest of the article at the link above.

In the news: A “stirring” solution to algae problems?

February 6th, 2014 by
Jordan Lake in North Carolina suffers from a condition similar to Lake Erie – algal blooms that threaten wildlife and water quality. Due to nutrient runoff, the blooms continue to grow and pose a significant problem for the community that relies on it for water. 
 
While the EPA rules regarding processes and procedures to reduce runoff and mitigate the problem await implementation, there is a proposal for a potentially less expensive and more immediate way to reduce the algal blooms in the lake. 
 
“The N.C. General Assembly authorized a $1.44 million plan to put 36 floating water circulators into the lake. It’s a hefty price tag, but is actually one of the drivers for the experiment. If it works, the savings could be huge as costs for implementing the EPA rules are estimated at $1 to $2 billion.
 
Representatives from Medora Corporation, the company that will supply the mixers, say that the mixing process may confuse the algae, making them think they’re at different depths in the water. It could make them more vulnerable to viruses. The reps also say the mixers will work, claiming a 90 to 95 percent success rate in other lakes.”
Read more about the proposal at the link above.

In the news: Finding a better way to get rid of unwanted algae

August 6th, 2013 by

Each year, Great Lakes beach managers have to remove trucks full of slimy algae from the beachfront areas to keep them enjoyable for residents and visitors. But it can be a costly process and a regular need that could be met in a more environmentally friendly way. 

From The Great Lakes Echo

“Truckloads of the stuff are hauled to landfills every week or so, but beach managers want a greener and cheaper method of disposal.
 
‘Algae removal is sort of a routine beach-grooming thing that we do, but because it’s wet and heavy, it can be expensive to dispose of,’ said Cathy Breitenbach, director of Green Initiatives for the Chicago Park District, which is responsible for 26 miles of lakefront in the city. She’s hoping to find an alternative that saves taxpayers money and is more sustainable than taking it to the dump like the district does now.
 
Composting may seem like an obvious solution, but it’s not as simple as it sounds, say algae experts. Cladophora mats can harbor large concentrations of bacteria, including some potentially dangerous varieties.
 
‘We have evidence to show that E. coli bacteria are found in very high densities in Cladophora mats,’ said Murulee Byappanahalli, a research microbiologist at the U.S. Geological Survey’s Lake Michigan Ecological Research Station in Porter, Ind.”
Read the complete article at the link above to learn more about algae and the need for a greener, cleaner way to dispose of it.

 

In the news: Lake Erie once again at risk from toxic algae

June 24th, 2013 by

Lake Erie, one of the Great Lakes that began to rebound significantly thanks to the Clean Water Act and several cleanup projects, is being threatened by toxic blue-green algae. Fed by fertilizers and runoff, the algae can deplete oxygen levels in the water and be detrimental to the lake’s health.

From The Plain Dealer:

“The Western Basin of Lake Erie, located roughly from Toledo to Huron, is becoming seriously affected with toxic blue-green algae. During the summer months, the algal blooms have been so bad that swimmers have emerged from Lake Erie covered in green slime. So far, swimming in Lake Erie has not been prohibited as it was in Grand Lake St. Mary’s, however, the thick algal blooms are not very inviting to swimmers and tends to affect the taste of our drinking water. 

The enjoyment of Lake Erie for boating and fishing has also become hampered by the costs to repair clogged engines and the costs of reduced economic drivers, such as fishing charters and other recreational opportunities. We are dangerously close to severely restricting our use and enjoyment of one of the world’s greatest natural resources.”

Read the complete article at the link above to learn more about threats to Lake Erie, and read more about Great Lakes health issues and research at our web page.

A delicious solution to Great Lakes algae issues?

September 25th, 2012 by
Runoff from a variety of land uses, including agriculture and industry, has been identified as one of the primary causes of harmful algal blooms (PDF) in the Great Lakes and surrounding waterways. The danger of these algal blooms comes in the form of botulism outbreaks, toxins, and harmful metabolites – all of which can have serious consequences for native plants, fish, and human health. 
 
One potential solution that has been in use in Ohio is the planting of radishes, not only to help manage water and runoff, but also to improve soil quality for agricultural users. 
 
“The radishes planted in northwest Ohio go in about this time of year and are left in the ground to die, explained our host, Allen Dean. Planting doomed radishes, it turns out, is an innovative technique he has used in recent years to improve soil nutrients and reduce runoff from his Williams County farm.
 
Here’s the basics on how it works: Farmers plant seeds for a plant called an oilseed radish. It doesn’t actually have to be that plant, but it needs to grow a foot or longer into the soil during the fall in a tubular shape, like a carrot or a parsnip. It also needs to grow a fair amount of foliage up on the ground. Radishes are usually more affordable.
 
It’s important that the plant drill down into the soil so that when it dies, usually during a mid-January freeze, it decays and leaves behind a v-shaped hole for snow and water to penetrate deeper. The decayed radishes Dean showed us looked like organic socks.
 
Oilseed radishes are particularly good at absorbing nutrients from the surface and sending them down into the soil as the tubular plant drills it way into the ground.”
Read the complete article above to find out more about how these plants are helping farmers and protecting the Great Lakes waters at the same time.

In the news: Identifying potential causes of harmful algae in Lake Erie

September 10th, 2012 by
A two-part article on WKSU’s website delves into recent research attempting to understand the causes of harmful and often very large algal blooms in Lake Erie. The potential negative impacts these blooms can have include depleting nutrients from the waterway, endangering fish and wildlife health, and causing economic concerns by prohibiting or discouraging recreation, tourism, and other industries. 
 
Part one of the article delves into one major contributor identified by the research: agriculture. 
“Financial viability is the bottom line for most farmers here along the Maumee River. The Maumee passes through 4.5-million acres of farmland before entering Lake Erie at Toledo. Along the way it picks up a lot of topsoil from farm fields. Attached to that soil are fine particles of phosphorus, one of the nutrients that helps crops grow, but also feeds algae blooms. No-till farming has reduced particulate phosphorus runoff by nearly 40-percent. But researchers from Heidelberg University say their thirty years of water quality data shows that another form of phosphorus – called dissolved phosphorus – has risen dramatically in recent years. And to reduce that nutrient enough to curb Lake Erie algae blooms will take a whole new set of techniques.” 
The second article describes another common source of phosphorous and other problem substances – stormwater and sewage. 
“The sport fishing industry, beach resorts, amusement parks – all took a hit from the 2011 algae outbreak. Connor says cities …not just farms…have to do more to stay on top of it.
Overflows from sewage systems that collect storm water and waste water are a fairly regular occurrence in Cleveland, Toledo, Detroit and other communities around the lake. And it’s a huge cost to fix it.”
There is a lot of interesting information in both articles, and the occurrence of and concern over these algal blooms isn’t limited to Lake Erie. All of the Great Lakes and other nearby waterways can be susceptible, so the results of studies such as these are important in helping communities prevent the same types of problems in their areas. Our friends at Michigan Sea Grant have produced a brochure for beach managers that outlines more information about algal blooms, and IISG has produced a card for homeowners that explains how to properly care for your lawn without contributing to the phosphorous problem.
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