Aqueducts on the C&O Canal

The Chesapeake and Ohio Canal (C&O) used 11 navigable aqueducts to carry the canal over rivers and streams that were too wide for a culvert to contain. Aqueducts, like locks and other masonry structures, were called "works of art" by the canal board of directors.

In addition to these 11 aqueducts, there was the Alexandria Aqueduct, which connected the C&O Canal with Alexandria, Virginia, and the Broad Run Trunk Aqueduct, made of wood, and was originally a double culvert, and never listed in company records as an aqueduct.

The aqueducts of the C&O, unlike the Roman aqueducts, were built with inferior materials and cement, and did not have a long life expectancy. Usually the trash from the floods did the most harm to the aqueducts.

The Seneca Aqueduct (#1), located in Montgomery County, Maryland, also included a lock built in (Riley's Lock). The aqueduct traverses Seneca Creek and was built from 1829 to 1832. It collapsed in 1971 due to flooding.

There was a stone cutting mill just at this point, on the upstream side. It cut stone from Marble Quarry (above White's Ferry on the canal), and Cedar Point Quarry (which was around Violette's lock, one lock downstream), as well as the quarries of Seneca sandstone. It was powered by canal water diverted into a mill race to a turbine.

This aqueduct was also the site of an incident in 1897 when the passenger steam packet boat leaving the aqueduct collided with a freight boat loaded with watermelons. There were no injuries to the passengers when the boat sank, but the local people collected free watermelons floating in the turning basin just above the aqueduct.

This "unofficial" aqueduct crosses Broad Run in Montgomery County. It was originally two stone culverts 16 feet (4.9 m) long, and listed as Culvert #44½. Construction originally began in 1829, on section 53, and after several contractors worked on it, was completed in 1833. It later washed out in 1846. A wooden trunk was put in to keep navigation open. It deteriorated until it could not be repaired, and was rebuilt 1856. Troops burned it during the American Civil War, and it was replaced again. The wood rotted and constantly had to be replaced. Although it was an aqueduct, the company records still listed it as a culvert.

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