Historic Preservation of Halfmoon Canal Structures
Town of Halfmoon, New York
This historic preservation project focused on reestablishing the 19th century Champlain Canal in order to protect vital water resources: a naturally constructed and important wildlife habitat and a man-made waterway which now provides a glimpse of the community’s rich history.
The project included structural rehabilitation of a multi-use, stone structure, a unique combination of a culvert and waste water weir that also serves as a bridge maintaining access along the original towpath. The historic structure includes a waste water weir, which is a magnificent example of ingenious 19th century engineering, designed to rely on gravity to channel the excess water from the canal before modern pumps and electricity were available to perform the task. The structure was constructed in 1823 of large blocks of rectangular cut stone stacked so expertly no mortar was required to keep them in place. After nearly 200 years, the culvert was still in relatively good condition. However, a portion of the interior walls had collapsed, allowing water to erode the remaining portion of the structure.
The team utilized 3D laser scanning technology to develop archaeological documentation of the historic structures. The scan data created a baseline digital inventory of the culvert and waste water weir. 3D scanning allowed the team to capture imagery, extract precise measurements and provide a complete data set to the engineering staff. This data was referenced throughout the project and was useful during design as it provided a visual aid and quantified the extent of degradation and necessary repairs.