Feature Stories

A lock on history

20 years after the Gronauer Lock dig

By Craig Leonard
Editor’s Note: Fort Wayne Monthly is proud to welcome the writing of Craig Leonard to our pages with this article. Leonard is a historic preservation consultant who has worked on many projects, including restoration of the Indiana State Capitol and the excavation and restoration of the Gronauer Lock, whose story he continues here.


Tim Doyle waters down the exposed lock timbers to prevent deterioration. (Photography from Library of Congress-prints and photographs division)
The east gate sill, looking out of the lock chamber toward the east forebay. (Photography from Library of Congress-prints and photographs division)
With the lock gates closed, the canal boat is ready to move up or down a level. (Photography from Library of Congress-prints and photographs division)
The east gate area’s gate recess shows the timber walls and hand-forged spikes that held it together. (Photography from Library of Congress-prints and photographs division)
The week before Thanksgiving marks the 20th anniversary of a significant event in Allen County and American history — the excavation and salvage of the Gronauer Lock, officially known as Lock 2 on the Wabash and Erie Canal. Its exhibit at the Indiana State Museum in Indianapolis is being redesigned now, and a date for its reopening has yet to be set, so spring might be a better time to go visit this irreplaceable piece of our history.

The canal once extended from Toledo to Evansville and was the longest manmade waterway in the world, after China’s Grand Canal. Of the 73 locks on the Wabash & Erie Canal, 39 were of the timber crib-style construction used for the Gronauer Lock.

Though commonplace in the 19th century, no plans of wooden crib locks have survived; only the written instructions about how to build them. These specifications use many terms then commonly understood whose meaning has since been lost; interpreting those terms led to much scholarly debate about how these locks were built. Discovery of the Gronauer Lock made it possible to finally interpret these terms from a genuine example, the first and only one ever found in the U.S.

According to Tom Castaldi, author of Fort Wayne Monthly’s regular feature, “Along the Heritage Trail” and a preeminent authority on Indiana canals, groundbreaking for the canal took place in Fort Wayne Feb. 22, 1832, and the first segment of the canal was completed to Huntington in 1835. Progress on the eastern leg of the canal was slower, but Henry Lotz built the Gronauer Lock in 1838. Timber locks were considered temporary structures to be used for perhaps seven years; in fact, the Gronauer Lock was rebuilt above the waterline in 1844 and again in 1861. The canal was ordered to be sold in 1874. The sale was completed by 1876. West of Fort Wayne the canal became a railroad right of way, but east of the city it became a drainage ditch that gradually filled with silt.

The lock takes its name from Joseph Gronauer, who operated it most of his life and lived in a brick Greek revival house that stood above the northeast corner of the lock. Gronauer was actually a tailor by trade; he rode the canal towpath into downtown Fort Wayne and worked in a shop on Columbia Street. The Gronauer House was demolished in 1944, when U.S. 24 was widened. At that time, the lock was to have been demolished; instead, parts of it were used elsewhere as fill and the remainder was burned down to ground level and covered over.

In June 1991, the lock was rediscovered when utility crews relocating telephone cables exposed it in preparation for the nearby construction of the interchange of U.S. 24 and I-469. The discovery coincided with New Haven Canal Days. Volunteers from the Canal Society of Indiana soon verified the significance of the discovery and maintained displays at the site to explain its significance. Mayor Lynn Shaw convened an ad hoc committee to respond to the state’s interest in the lock for preservation; New Haven was eventually certified as a qualified party and awarded $100,000 to fund the removal of the lock by Dec. 1, 1992. Work began at the end of July 1992.

City Councilman Tim Doyle and I co-directed the effort: Doyle perfected a method of using ground water to keep the timbers wet and organized the crew that did the excavation; I photographed, measured and numbered the approximately 2,000 pieces of oak and poplar timbers that were eventually uncovered.

The lock had a channel 15 feet wide and 100 feet long, with a fan-shaped entrance bay on its east end. The wood cribs behind the channel walls were filled with earth and stone to resist the outward pressure of the water in the channel. With its outliers, the overall size of the lock was 160 feet long and 40 feet wide. The channel walls, originally 15 feet tall, were now 7 feet tall on the north side and 3 feet tall on the south side.

The project enjoyed broad community support; local businesses donated tools and services; area restaurants donated lunches to feed the crews.
New Haven also found it had the ideal facility to store the excavated timbers: a former sewage treatment plant nearby not only had a concrete basin 80 feet in diameter and 8 feet deep, but there was an operable water well in an adjacent building.

In addition to the timbers, artifacts found in the lock included what turned out to be the most commonly found objects in canal-related sites: 46 pairs of leather shoes, many with soles patched where they would have met a shovel blade. Other artifacts included fishing tackle, a sewing kit, the octagonal glass bases of whiskey jiggers and bottles for whiskey and patent medicines. Several coins were found, including two 1789 Spanish silver dollars. By modifying a car jack, Tim Doyle was able to remove the 3,600 hand-forged nails that held the lock together.

In 1998, lock timbers were shipped to the University of South Carolina’s Institute of Archeology and Anthropology in Columbia, SC, which has the only facility capable of conserving such large timbers. Treatment consisted of immersing the wood in a tank of a water-soluble wax, polyethylene glycol, which displaced the water out of the wood and restored its mechanical properties. In 2001, the timbers returned to Indiana to become an exhibit at the Indiana State Museum. The New Haven Historical Society has retained one of the signature artifacts, a triangular mitre sill that was the threshold the lock doors closed against.

But the lock has retained many of its mysteries. In 2008, virtually all of the field notes and photographs from the excavation were lost when my house burned. Today some of the timbers remain in the storage tank, just a short distance away from the cemetery where Joseph Gronauer is buried.

Posted: Wed, 11/21/2012 - 2:40 pm
Last updated: Wed, 01/23/2013 - 2:20 pm