Near Clear Spring in Washington County, Maryland — The American Northeast (Mid-Atlantic)
Protecting Cultural Resources
Chesapeake and Ohio National Historical Park
— National Park Service, U.S. Department of the Interior —
Floods occur at regular intervals in the Potomac Valley. Between 1829 and 1998 there have been 144 recorded floods or high water occurrences. repairing flood damage was a continuing battle for the C&O Canal Company and is still a problem for the National Park Service. During periods of low water, the remains of the original crib and rubble dam, destroyed by floods can be seen downstream from the present dam built in 1857.
In 1998, the guard lock and flume were filled with soil to halt the collapse of the stone walls. A section of the towpath that was collapsing was replaced with "Roller Compacted Concrete (RCC)" which is a concrete mix with a small amount of cement and a high amount of gravel. The stone for the aggregate was acquired locally to match the stone already used here. The RCC is spread and compacted by a roller and does not require formwork like conventional concrete. By filling the lock and bypass flume and reconstructing the towpath and guard dike, the National Park Service is trying to protect the historic structures from future flood damage.
Erected by National Park
Topics and series. This historical marker is listed in these topic lists: Natural Resources • Waterways & Vessels. In addition, it is included in the Chesapeake and Ohio (C&O) Canal series list. A significant historical year for this entry is 1829.
Location. 39° 36.42′ N, 77° 55.316′ W. Marker is near Clear Spring, Maryland, in Washington County. Marker is on Dam No. 5 Road, on the left when traveling west. Touch for map. Marker is in this post office area: Clear Spring MD 21722, United States of America. Touch for directions.
Other nearby markers. At least 8 other markers are within 4 miles of this marker, measured as the crow flies. Stonewall Jackson at Dam 5 (here, next to this marker); Dam No. 5 (about 300 feet away, measured in a direct line); Mule Power (approx. 1˝ miles away); Four Locks (approx. 1˝ miles away); a different marker also named Four Locks (approx. 1˝ miles away); McCoy's Ferry (approx. 2.6 miles away); Lancelot Jacques (approx. 3 miles away); Clear Spring Veterans Memorial (approx. 3.3 miles away). Touch for a list and map of all markers in Clear Spring.
More about this marker. Caption for photo on left side of sign: Guard Lock and Dam Number 5 with Electric Generating Plant on Opposite Bank.
Caption for photo on right side of sign: Looking Upstream at Guard Lock During Operation Period of Canal.
Related marker. Click here for another marker that is related to this marker. To better understand the relationship, study each marker in the order shown.
Credits. This page was last revised on September 29, 2020. It was originally submitted on December 5, 2009, by Robert H. Moore, II of Winchester, Virginia. This page has been viewed 681 times since then and 5 times this year. Photos: 1, 2. submitted on December 5, 2009, by Robert H. Moore, II of Winchester, Virginia. • Craig Swain was the editor who published this page.