Maps: Didymo Locations and Survey Sites

Didymo was found in early 2008 in Gunpowder Falls below Prettyboy Reservoir in Baltimore County. Since July 2008, DNR and Baltimore County/DEPRM have been monitoring Didymo occurrence monthly in the Gunpowder Falls between Prettyboy and Loch Raven reservoirs.

Below are maps containing Didymo locations and survey sites by month.

Legend for Didymo Maps 

October 2008

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September 2008

Page Viewer - September 2008

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August 2008

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July 2008

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