Culverts: A System of Support

Underlying the 184.5 mile C&O Canal towpath, more than 200 culverts were built to pass smaller creeks and streams under the canal and into the Potomac River. These engineering marvels may not be readily seen as we bike and hike the trails, but they are critical for towpath continuity.

Historic photo of culvert 51 by National Park Service

Culvert 51 at Whites Ferry by Paul Graunke

Culverts support the entirety of the towpath and help to manage flood waters and debris. Their effectiveness relies on them being in good repair and debris-free, an increasing challenge as the park experiences a rise in storm intensity and frequency. A culvert collapse can be devastating; in 1907, an Erie Canal culvert gave way, creating a huge hole in the bottom of the canal and completely destroyed five canal boats.

C&O canal culverts have been routinely damaged or breached, including culvert 82 over Little Catoctin Creek. This culvert was breached in May 2018 due to flash flooding and replaced by a bridge in 2024, costing $1 million.

In the six years before the project was completed, there was a low water crossing that routinely flooded, disrupting towpath continuity. Canal Towns and other partners helped fund a shuttle to move visitors safely around the washout during high water events. Without this support, the towpath remained impassible and presented challenges for many visitors who travel the full 184.5 mile length.

While we might not notice culverts when they’re functioning, it is difficult to miss the damage caused to the park when they fail. The number of culverts in need of repair continues to grow each year, as well as the cost of repairing and maintaining them. In 1872, just over 20 years after completion of the C&O Canal, an engineer made an inspection of the canal and determined that culverts needed repairs totaling $2,867.42, or $75,927.40 today.

This year, INFO FROM JOE