Lock 51 at Mile 122.7 on the Chesapeake and Ohio Canal towpath
Lock 51 is located 300 yards downstream from the Bowles House (former Hancock Visitor Center) at Mile 122.7 on the C&O Canal towpath. There is parking at the Bowles House. See the Locks and Lockhouses web page for an interactive location map.
There is nothing left of Lock 51 on the Chesapeake and Ohio Canal other than its stone retaining walls and sluice. If you look at the lock from downstream, you can see the sluice on the right side. A sluice is a drainage ditch that runs parallel to the lock. When the upstream gates are closed, the sluice allows water to flow around the lock instead of backing up into a pool of excess water that could spill over the banks of the canal or put additional pressure on the lock gates. The water empties back into the canal just past the downstream gate. All locks had sluices, but today many have been filled in with dirt or are covered in vegetation and hard to spot.
Downstream end of Lock 51 on the Chesapeake and Ohio Canal
On the opposite side of the towpath from the lock is the ruins of Lockhouse 51. A lockhouse is the residence of the man who is hired to operate the lock. In addition to a yearly salary, he and his family—almost all lockkeepers were family men—lived in the company provided lockhouse and had use of an acre of land for farming. Those who tended multiple locks got extra money per lock, up to two. The locks had to be very close together for the C&O Canal Company to assign multiple locks to one person.
Operating the lock was a year-round, 24-hour-a-day job. When a canal boat approached, the captain would blow a horn to notify the lockkeeper. If it were nighttime, somebody had to wake up and go to work. Of course that’s the benefit of being a family man—your kids had to get up for the late night and early morning arrivals!
Ruins of Lockhouse 51 at Mile 122.7 on the Chesapeake and Ohio Canal towpath
Interior ruins of Lockhouse 51 on the Chesapeake and Ohio Canal
Chiseled into the front wall of the lockhouse are the words Upton Rowland March 29 + 1845. Rowland was the lockkeeper in charge of both Lock 51 and Lock 52 from 1840 until 1848.
Upton Rowland inscription on the wall of Lockhouse 51 at Mile 122.7 on the Chesapeake and Ohio Canal
About a half mile downstream of Lock 51 is the ruins of a waste weir gate. A waste weir is a channel connected to the canal that allows water to be drained, typically when repairs have to be made. Gates of the weir are opened, and water flows out of the canal and into either the water source itself—in this case the Potomac River—or a pond of some sort. What is odd about this waste weir is that it is on the opposite side of the canal from the river, and there is no pond to hold the water. Where did the water go? A culvert runs underneath the canal and towpath, so the water drained into the Potomac via the culvert. The most likely reason for this is that the terrain is quite steep on the river side of the canal, so there is no room for a waste weir.
Ruins of a waste weir gate about a half mile downstream from Lock 51 on the Chesapeake and Ohio Canal
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Last updated on June 26, 2026
