Algae: A Slimy Solution to Improving Baltimore Harbor’s Water Quality

By Nancy Grundahl

Algae are in the spotlight and – this time – for all the right reasons.  That slimy greenish stuff you sometimes see in lakes and at the beach is now being used in a pilot project to see if it can help clean up the water in the Baltimore Harbor.  Algae blooms are normally in the news as the result of excess nutrients that rob water of oxygen.  But this controlled growth of algae is part of an initiative that aims to make the Inner Harbor swimmable and fishable by 2020.

How does it work?  Algae that are naturally in the harbor flows over a mesh screen. There it attaches and grows, removing nutrients and carbon from the water in the process.  Every week, the algae are harvested and then can be used as a fertilizer or converted into fuel.

This innovative pilot is part of Baltimore’s Healthy Harbor Plan to make the harbor cleaner and greener.  And, if it works, plans are to expand the algal pad to at least an acre, filtering millions of gallons of water each day.  If you want to see what a smaller scale version of an algal turf scrubber looks like, view this lively video:

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2012 marks the 40th anniversary of the Clean Water Act, the nation’s law for protecting our most irreplaceable resource.  Throughout the year, EPA will be highlighting different aspects of the history and successes of the Clean Water Act in reducing pollution in the past 40 years.  The month of June focused on Fishable Waters.

About the author: Nancy Grundahl has worked for the Philadelphia office of EPA since the mid-80’s. Nancy believes in looking at environmental problems in a holistic, multi-media way and is a strong advocate of preventing pollution instead of dealing with it after it has been created. Nancy likes to garden and during the growing season brings flowers into the office. Nancy also writes for the EPA “It’s Our Environment” blog.

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