The harmful consequences of fertilizing your yard

Green algae bloom along the shores of Lake Erie can be seen in this photo taken Oct. 9, 2011, by the NASA Landsat-5 satellite. Image courtesy of NASA.

It's that time of year when many of us are beginning to fertilize our lawns and gardens. What many of us don't think about is how that practice is tied to a yearly water quality issue in Lake Erie. The problem can be seen just a mile off the shores of Bay Village in satellite images.

Last year was one of the worst years on record for a water quality issue resulting from human-induced algal blooms. These blooms, in turn, result in a problem known as the Lake Erie dead zone. This is a zone of oxygen-depleted water that has grown to cover as much as half of our lake.

Many aquatic organisms, including fish and insects, cannot live in this oxygen-depleted zone. Therefore, it disrupts the web of life that helps keep our aquatic ecosystem healthy. Furthermore, some species of algae contain neurotoxins that reach high enough concentrations during some blooms to have a severe impact on wildlife and to close area beaches.

How does fertilizing our lawns contribute to the problem? Fertilizer contains the nutrients phosphorus and nitrogen. Rain water and sprinkler water carry some of fertilizer's nutrients into nearby storm sewers and streams. Storm sewers and streams, in turn, drain directly into the lake without any filtration. The addition of fertilizer's nutrients into the lake water contributes to algae's population explosion since algae feed on phosphorus and nitrogen. This sudden population explosion is the algal bloom mentioned above.

When the algae die, they sink to the bottom of the lake where they are decomposed by bacteria. It is the decomposition of these dead algae by bacteria that removes the dissolved oxygen from the water and creates the dead zone.

According to Jeff Reutter, director of the Ohio Sea Grant and Stone Laboratory at Ohio State University, phosphorus levels are back up to the level of the 1970s when Lake Erie was considered a dead lake. Other significant human sources of nutrients feeding these blooms include combined sewer overflows, agricultural fertilizing, sewage treatment plant discharges and animal waste.

Each of us can be a part of the solution. Reduce or eliminate fertilizer from your yard and clean up your animal waste. If you are mulching your grass during the growing season rather than bagging, then your lawn will naturally get nutrients returned to the soil from the lawn clippings.

If you are going to fertilize, use a fertilizer that contains no phosphorus or use an organic fertilizer. At a minimum, sweep excess fertilizer off of the sidewalk and street and create a buffer zone by not fertilizing near storm sewers. Installing a rain barrel or rain garden also helps by slowing the flow of water to the lake. These options are healthier for you, healthier for our pets, healthier for our kids, healthier for our neighbors and healthier for our lake. Consider implementing these practices this season.

Check out www.bayvillagegreenteam.com for more tips on maintaining a healthy lawn and garden with less water and little or no fertilizer. Thank you for being a part of the solution!

Patrick McGannon

Patrick McGannon is an active member of the Bay Village Green Team with a degree in Biology.  He has been a resident of Bay Village for 32 years.

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Volume 4, Issue 6, Posted 11:51 AM, 03.20.2012