Lake Erie’s Record-Breaking Algae Bloom May Become the Norm

By Breanna Draxler | April 1, 2013 2:01 pm

Landsat image of the 2011 algae bloom in Lake Erie. Image courtesy of NASA’s Earth Observatory.

In 2011, Lake Erie experienced the largest algae bloom in its recorded history. At its peak in October, the mat of green scum on the lake’s surface was nearly four inches thick and covered an area of almost 2,000 square miles. That’s three times larger than any other bloom in the lake, ever. Plus it was toxic. Now research shows that such an event may become increasingly common.

Algae blooms result from an excess of nutrients like nitrogen and phosphorus in the water, which throw aquatic ecosystems out of whack. The algae feed off the nutrients and grow so thick that they block sunlight, preventing other plants from photosynthesizing. And as the algae die, bacteria consume copious amounts of oxygen to decompose them, killing fish and other animals in the process. When the nutrient-loading gets really bad, it can sometimes lead to hypoxic, low-oxygen conditions, resulting in ecological dead zones like the one in the Gulf of Mexico.

To make matters worse, certain strains of blue-green algae are toxic, which makes these blooms dangerous to more than just lake-dwelling life. In the case of the 2011 bloom in Lake Erie, the researchers determined that blue-green algae accounted for the majority of the bloom, and concentrations of the toxic stuff reached 4,500 μg/L, which is 225 times greater than the maximum that the World Health Organization recommends for water used for swimming and boating.

One of the major source of nutrient loading in lakes is agricultural runoff from within a lake’s watershed—the area of land which drains to the lake. After nutrient loading in Lake Erie and the rest of the Great Lakes got really bad in the 60s and 70s, the U.S. and Canadian governments implemented the Great Lakes Water Quality Agreement to reduce nutrient loading to these iconic bodies of freshwater. For the next few decades, the agreement showed promising results, but in the 90s the nutrient concentrations began to creep back up.

In the years leading up to the 2011 bloom, the number and size of farms in Lake Erie’s watershed didn’t really change much, so what caused the massive explosion of algae growth? Researchers say it’s a combination of how farmers apply their fertilizer, and changing climate conditions, according to the study they published today in the Proceedings of the National Academy of Science.

The bloom in the western portion of Lake Erie, shown here in comparison to the other four Great Lakes. Image courtesy of NASA’s Earth Observatory.

When the weather allows it, farmers will apply their fertilizer in the fall instead of having to wait for the ground to thaw in the spring. And instead of injecting the fertilizer into the soil, they typically just apply it to the surface. Tilling the soil can expose even more nutrients. Most years, these methods work well for the farmers and the lakes alike, but the weather in 2011 turned the tables.

Conditions were ideal for fertilizer application in the fall before the 2011 growing season, which meant that many farmers spread it on thick. But a wet spring brought a series of major storms that washed tons of this nutrient-rich fertilizer and soil into Lake Erie. Warm weather and calm winds made it worse. The water in the lake wasn’t circulating much, which gave the algae a long, undisturbed incubation period. And after the algae bloomed, conditions stayed warm and still for most of the season, so algae stayed at the surface instead of being blown around by the wind and mixed into the water column to flush it from the system.

Unfortunately the 2011 bloom wasn’t just a fluke. The researchers say the massive bloom in 2011 will be a vision of the future unless drastic policy changes are implemented.

Nutrient loading dropped dramatically in 2012, perhaps because most of the Midwest was experiencing a drought. But the researchers say that with biofuel production on the rise, an increasing number of acres will be planted with fertilizer-intensive crops like corn in the years to come. And climate change suggests a future with warmer weather and larger, more frequent rainstorms, meaning blooms like the beast in 2011 are likely to become the norm rather than the exception.

Want to read more? Check out DISCOVER blogger Tom Yulsman’s post on toxic green slime.

CATEGORIZED UNDER: Environment, top posts
  • Eric Hoffman

    Agri-business as usual, welcome to the cornpocalypse

  • vseidita

    Couldn’t we harvest the nutrient rich algae and turn it into fuel? Any scientists out these care to comment?

    • G0f0rIt

      Q1) So far nearly every attempt at engineering the environment, meant to compensate for damages done, has backfired. Q2) The scientists already have spoken on what is needed: Less, way less CO2 billowing energy use. In general, lowering consumption, and btw, stopping population growth wouldn’t be half-bad.

      • alternatesteve2

        What does that have to do with engineering the environment?

        Also, just lowering consumption isn’t going to do us a darn bit of good unless we also ramp up renewable usage as well.

    • Philip Rutter

      These are “wild” algae. Attempting to turn them into fuel would be the same as trying to make artisan cheese- from chipmunks. They’re not in the business. Can it be done? Yes. Cost effectively? No way. It MIGHT, possibly, be harvested, squeezed just enough to remove water without breaking cell walls, and composted for fertilizer. But again- it would cost 10x the amount of nice fresh fertilizer already on the market.

    • Dylan Mead

      I doubt it would be efficient, in the sense that you get out more energy than you put in, to turn the lake algae into fuel but I haven’t crunched the numbers so who knows. What I do know is that there is a lot of bio available nutrients there. I bet you could grow some great veggies with algae compost.I’m a physicist so not exactly my area of expertise.

    • alternatesteve2

      Yes, we certainly could, if we tried. Sadly, though, it probably wouldn’t be…..thanks to Big Oil.

  • Pablo Cree

    Something has to give?

  • Plainer

    Japan has similar problems and utilze technology that oxygenates the water from the bottom to the top to alleviate if not eliminate the algae problem.

  • sharkync

    How close is this lake to Detroit?

    • organicroseski2

      One of the primary feeds is the Detroit River. States surround Lake Erie are, MI, OH, PA, NY, and Ontario, Canada.

  • Adevarul

    This can be explained as the “long loop” circle of life model for the coal industry. The algae will choke off massive amounts of life in the lake that will sink to the bottom. If you are around in an eon or two, viola! more coal.

    • bensbro

      coal no….petroleum maybe…you need good swampy material to make a good coal….process is peat—lignite–coal…. for need dead microorganisms raining out of water and falling to the floor of the water source.

  • herbert


  • Alexander R. Hombek

    The regulations are there. They are just not enforced. Friends of politicians want to do something but don’t want to be fined. Solution: ask politicians to cut back regulatory bodies so that they can do what they want. Politicians, liking money and jobs for friends and family, go along with it. It’s to the point where things are getting unsafe for food and water now. How’s voting Reform working out for you now?

  • Patrick∞

    Is the bloom result of local SW Lake Erie practices or is that the collection basin for fert and other nutrients used up stream in Great Lakes?
    Remember this problem being top of mind in 70’s, called it eutrophication and Lake Erie was described as suffocating, oxygen starved. Concerted, cooperative bilateral effort was advertised as effective.
    Mother Nature reminds that sustained harmony requires vigilant, preventative practices.

  • Bill Evans

    NASA reports dead zones on all coasts of the US, at the mouths of major river systems, where cities grow.

    It’s not just agribusiness. Our government allows the pollution of “free” water – lack of infrastructure, oversight and prosecution – for one primary reason. Eventually, we will all have to buy clean water.

  • Kenn Amdahl

    The real problem is that cyanobacteria produce 80 varieties of toxin. Your water department only has to test for four of these. Some of the ones they don’t test for have been implicated in Alzheimers and ALS. That’s where the title of my book came from (which will be free as a Kindle this Saturday)

  • disqus_DMFwMUfw8h

    I have noticed that a lot if cottonwood trees grow around lake Erie and that the cotton is blow into the lake and grows algae on it. I have seen areas of cotton filled algae that are 4the feet thick. Could this be part of the problems?

  • Bliss

    We have blue-green algae in our high mountain lakes at 5000ft. No agriculture run-off there.

  • Carley H. Young

    uptil I looked at the check 4 $5692, I did not believe that
    my brother truley erning money in their spare time on their apple labtop..
    there uncle has been doing this less than 7 months and recently took care of
    the loans on there condo and purchased Lotus Carlton. read more at, fab22.comCHECK IT OUT

  • organicroseski2

    Did they look at lawn care as a % of the problem? The farms were being sold to home builders before the building boom stopped. I am getting many mailings each spring to sign up for a fertilized lawn. A “once” farm, a mile from me is being prepared for homes now. There are a lot less farms in Michigan. Same goes for Ohio.


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