Water turbines that operated the lock gates without the need of electricity, diesel or gasoline engines are the last known examples of the machinery that typified lock and dam construction during the 1920s.
The equipment is listed in the Library of Congress and has been documented by the U.S. Department of Interior’s National Park Service.
It’s no wonder both the U.S. Army Corps of Engineers, which operated the lock and dam from 1926 to 1994, and Greensboro Borough, which now owns the lock house, want to preserve it.
The borough recently applied for a state grant to complete an environmental assessment and cleanup of the lock house.
“The building and equipment have relevance as part of the Monongahela River lock and dam system,” said Darlene Urban Garrett, the borough’s Elm Street manager.
The borough now has a local investor who wants to operate a “boutique manufacturing company” in part of the building. Historic aspects of the building would be preserved and the building opened for tourists and others, Garrett said.
The Mon is a significant part of Greensboro’s history, serving as a main thoroughfare for early settlers and providing an important means of transportation for the town’s early industries of glass, tile and what Greensboro has become most known for – pottery.
The development of the system of locks and dams on the Mon further promoted commerce, especially during the coal industry’s growth in the early to mid-20th century.
Lock and Dam 7 was built between 1923 and 1926 at river mile 85, just south of Greensboro.
It replaced an earlier lock and dam built at river mile 82.3 by the Monongahela River Co. The older structure, which included a timber crib dam and a 50-by-190-foot lock, began operation in 1883.
In 1897, the lock and dam system on the Mon was acquired by the federal government, which began system improvements to accommodate the increase in coal-related traffic and larger tows. This included replacement of the old Lock and Dam 7.
The new lock and dam had a concrete fixed-crest dam, a 56-foot by 360-foot lock and a two-story lock house, according to a history of the lock house prepared as part of a nominating application for the National Register of Historic Places.
Operations of the locks did not require power from electrical, gasoline or steam engines, the document said. A water turbine provided the oil and air pressure needed for opening and closing lock gates and filling and emptying valves.
The turbine system was used instead of an electrical system because of the fear electric motors would be damaged by frequent high water on this part of the river, the document said.
The lock house itself is built from reinforced concrete. It is rectangular except for the upstream wall which is bowed and resembles the bow of a ship. The upstream wall was bowed, Garrett explained, to protect it in times of high water.
Lock and Dam 7 operated through 1994, when it, too, was determined to be inadequate to handle the size of the tows on the river.
A new lock and dam was built downstream at Grays Landing with an 84-by-720-foot lock. It was completed in 1994.
Lock and Dam 7 officially closed July 30, 1994. The concrete dam, lock river wall and gates were removed. The lock’s land wall, lock house, lock esplanade and access bridge were left in place.
Borough officials had proposed saving the lock house because of its historic significance.
In 1995, the borough received the deed to the property from the corps. A pamphlet prepared for the ceremony marking the official transfer of the deed on Dec. 8, 1985 stated:
“This was the last surviving unmodified example of the first generation of government owned projects which replaced those of the privately owned Monongahela Navigation Company.”
“It retained its original operating machinery without any significant changes or replacements. The engineering design and construction materials typified navigation engineering in the 1920s.”
The Corps deeded the property to the borough with a “historic preservation covenant” requiring preservation of the equipment inside, Garrett said.
Since obtaining the property, the borough has tried to find a use for the building as well as the means to preserve it.
The grant will give the borough money to conduct an environmental assessment of the building and complete remediation. Machinery inside continues to hold hydraulic fluid used when the lock was operational, Garrett said. Paint on the walls also must be tested for lead and removed, she said.
The proposed use of the building for a small manufacturing operation will provide a good opportunity to use the building and preserve it, Garrett said.
“This is a very exciting opportunity,” she said. “This business facility will serve as an anchor for tourism in Greensboro and in Greene County.” n?
