Anatomy of a Tidal Marsh

Anatomy of a Tidal Marsh (HM21Z3)

Location: Alexandria, VA 22307 Fairfax County
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Country: United States of America
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N 38° 46.218', W 77° 2.989'

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George Washington Memorial Parkway

Your body has a heart and blood vessels to carry nutrients to your tissues, lungs to breathe, kidneys to filter out pollutants, and skin to protect you. When you look closely at Dyke Marsh, you can find natural systems that do all the same things.


Purple and blue on this map show the winding channels of the marsh, called guts, and the Potomac River. Tides pump Chesapeake Bay saltwater up the Potomac River and into the marsh. There it mixes with fresh water, nutrients and sediments.

Green plants act like kidneys, filtering pollution from the water. Marsh plants also slow down the movement of sediments, produce oxygen, and capture nitrogen.

Wetland forests, shown here as the mixed mosaic of green, yellow, and blue at the left, act like a protective skin. They anchor the shoreline and reduce erosion, sheltering Dyke Marsh and the people who live nearly.
HM NumberHM21Z3
Placed ByNational Park Service, U.S. Department of the Interior
Marker ConditionNo reports yet
Date Added Sunday, October 1st, 2017 at 7:03am PDT -07:00
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Locationbig map
UTM (WGS84 Datum)18S E 321922 N 4293282
Decimal Degrees38.77030000, -77.04981667
Degrees and Decimal MinutesN 38° 46.218', W 77° 2.989'
Degrees, Minutes and Seconds38° 46' 13.08" N, 77° 2' 59.34" W
Driving DirectionsGoogle Maps
Area Code(s)703
Closest Postal AddressAt or near Dyke Marsh Trail, Alexandria VA 22307, US
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