We did it before, and we can do it again.
We’re talking about the resurgence, and causes, of recent algal blooms in Lake Erie, shallowest of our Great Lakes.
A September 2009 bloom on the southeast Lake Erie shore of Pelee Island, Ontario, Canada, 5 miles north of the international line. Credit: Tom Archer/Michigan Sea Grant.
People have contributed to the comeback of this green menace in Erie, a lake that touches Ontario in Canada and Michigan, Indiana, Ohio, Pennsylvania and New York in the United States.
But we’re also prepared to deal with this excess muck, both from recent experience and as part of new science from the Lake Erie Ecosystem Priority.
The IJC project, also known as LEEP, has involved dozens of scientists from our two countries, who’ve worked to provide scientific and policy advice to reduce nutrient loads and harmful algal blooms. The result is “A Balanced Diet for Lake Erie: Reducing Phosphorus Loadings and Harmful Algal Blooms.”
The report addresses the decline in Erie water quality over the past decade. Deteriorating water quality has affected the health of the ecosystem, along with drinking water supplies, fisheries, recreation, and tourism and property values.
While algae is nasty, there are 16 ways to fight it.
The number refers to a set of recommendations in the “Diet.”
They come down to setting phosphorus reduction targets, cutting nutrient loads from agricultural and urban sources, and beefing up monitoring and research. We don’t want to do this all over in another 40 years if we can help it.
You’ve probably heard of phosphorus as it applies to lawn fertilizers. Phosphorus can make your lawn green, but it also can run off of surfaces like driveways, parking lots, and fields, and over-fertilize a water body.
That’s what’s happened to Erie, in simple terms. Too much of this nutrient isn’t a good thing for the lake. And the algae has returned, in part, because Erie is a different lake than it was in the 1970s, due to new stressors like invasive species (zebra and quagga mussels) and climate change (which has raised water temperatures).
A close-up of Microcystis bluegreen algae from Maumee Bay, Lake Erie. Credit: NOAA.
More intense precipitation events, especially in spring have also contributed to excess runoff from both rural and urban sources of nutrients.
The public has had, and still has a part to play in making this into another success story.
Public input has helped improved this “Diet” and the recommendations that go along with it.
And public support is needed to turn this lake around.
Lake Erie is receiving most of its phosphorus from non-point sources like construction, forestry, and especially agriculture.
Governments, from federal to local, need to retool environmental programs to focus especially on cutting “dissolved reactive phosphorus” --- the kind that’s more easily absorbed as fuel for algal blooms.
States need to ban the application of phosphorus-based fertilizers and manure on frozen ground, or ground covered by snow. At the same time the ban some jurisdictions have on the use of phosphorus for fertilizing residential lawns should be adopted throughout the basin..
Cities and towns need to invest in “green infrastructure” like engineered wetlands that manage and filter stormwater rather than sending it into drains, where it washes into rivers and streams that lead to Erie.
The “Diet” is now in the hands of Canadian and U.S. leaders.
More work is coming this year and next as part of LEEP to look at human health effects of toxic algae, computer models to better predict export of nutrients to the lake, and the economic impacts of algal blooms.
A MODIS satellite image of Lake Erie in October 2011, showing an algal bloom. Credit: NOAA Coastwatch.