The Guard Lock
Protecting the Canal from Flood Waters
— Wabash & Erie Canal Park Village —
Guard Lock Gates Keep The Canal Safe
Before you is a replica of a guard lock constructed of large cut limestone blocks. Guard locks often had only one set of gates as opposed to lift locks which always had two sets of lock gates. The purpose of the guard gates was to protect the Wabash & Erie Canal from flood waters. Guard locks would normally be built at the outlet to a basin such as a lake (slackwater) or river.
The engineering specifications required the Canal to be 40 feet wide and 4 feet deep. Guard locks and lift lock chambers were 15 feet wide and 90 feet long. Since the landscape over the 468 mile length of the Canal changes elevation a series of lift locks were necessary to raise and lower boats along their journey. Started in 1832 the Canal was dug with brute human force using shovels, sledge hammers, picks and pry-bars. Mules, horses and oxen were use to pull stumps, move rocks and logs and to scoop dirt and mud.
Nearby rivers, slack waters or lakes and streams provided a constant supply of water for operating the Canal. Too much water could cause erosion damage
Guard Locks were intended to be closed to protect the Canal during times of flooding but normally remained open when source water was adequate. Balance beams mounted on the top of the gates provided the leverage to open and close the heavy wooden structures.
Opening the gates against the water pressure bearing on them was made easier by operating smaller wickets. Mounted in the lower part of the gates, wickets or paddle gates allowed smaller amounts of water to pass through making the large gate movement an easier task.
A guard lock was sometimes combined with a
change bridge such as at Paragon (see the map)
where the towpath moved tow animals and tow
rope from one side of the canal to the other without
unhitching the boat. Towpaths sometimes changed
sides of the canal because it was entering another
body of water or unloading cargo in a side slip.
This photo of the historic Aldridge Change Bridge
is an example of how the Erie Canal was crossed in
Palmyra, New York.
Erected by Barry L. Nichols.
Topics and series. This historical marker is listed in these topic lists: Industry & Commerce • Waterways & Vessels. In addition, it is included in the Wabash & Erie Canal series list.
Location. 40° 35.35′
Other nearby markers. At least 8 other markers are within walking distance of this marker. The Post Office At Sleeth (within shouting distance of this marker); Sleeth Post Office was at McCoy's Station on the Monon R.R. (within shouting distance of this marker); The Depot (within shouting distance of this marker); Irish Canal Workers Cabin (about 300 feet away, measured in a direct line); The Itinerant Worker's Cabin (about 500 feet away); Mule Barn (about 600 feet away); "Pull Me" Boat (about 600 feet away); Canal Power (about 600 feet away). Touch for a list and map of all markers in Delphi.
Credits. This page was last revised on December 25, 2020. It was originally submitted on December 25, 2020, by TeamOHE of Wauseon, Ohio. This page has been viewed 44 times since then and 3 times this year. Photos: 1, 2, 3, 4. submitted on December 25, 2020, by TeamOHE of Wauseon, Ohio. • Devry Becker Jones was the editor who published this page.