Building the Monocacy Aqueduct

The Monocacy Aqueduct is one of 10 surviving engineering marvels built as part of the C&O Canal system begun in 1828. Located at mile 42.19 near Dickerson, MD, it is the longest and largest of the 11 original aqueducts built to carry the canal waters across the major river tributaries that drain into the Potomac River along the canal’s route.

This canal system is the most intact of 36 canal systems built in that pre-railroad transportation era. The C&O system was designated as a national park in 1971. (Our own C&O Canal guide Jon Wolz testified to congress on behalf of the park.)

Beginning in 1829, three separate contractors worked on the massive C&O Aqueduct 2 Project for four years at a cost of $127,900. The project chief engineer, Benjamin Wright, is considered to be the father of American Civil Engineering, having completed the Erie Canal prior.

The 516-foot-long aqueduct is primarily made of large granite blocks quarried at the base of Sugarloaf Mountain. Following damage from the 1972 Hurricane Agnes flood, a steel banding stabilizing system and steel rod reinforcing system were installed. A major engineering evaluation was begun, and the aqueduct was restored and rededicated in May 2005.