The bridge was designed by Alfred Landon Rives and built by the United States Army Corps of Engineers under the direction of Lieutenant Montgomery C.

[4] The bridge has an internal spandrel wall structure that contains nine additional smaller arches, which are concealed from view by exterior stone sidewalls.

[7] Previously, that honour had gone to the Grosvenor Bridge which crosses the River Dee in Chester, England and which was opened by the thirteen-year-old Princess Victoria (five years before becoming Queen) in October 1832.

Originally, the bridge was not intended to support traffic and so the conduit was only covered with soft clay.

On the vehicle side of the roadway, a concrete curb was added to reinforce and protect the stone parapet.

Integrated drainage and a simple balustrade of wrought iron railing was added to both sides, protection which had not previously existed.

Meigs, who had been promoted to the rank of captain, issued an order in March 1861 for a tablet on the east bridge abutment.

The final tablet design was modified with the title "Union Arch" and "Alfred L. Rives" was replaced with "Esto Perpetua" ("Let it last forever.").

[13] The bridge design process had begun in 1853, during the administration of President Franklin Pierce and the Secretary of War, Jefferson Davis.

Captain Meigs' 1861 order also called for a tablet on the west bridge abutment, with the title, "Washington Aqueduct" and listing the political leaders that were in office both at the start of the project and at its completion (i.e., Pierce and Davis; President Abraham Lincoln and Secretary of War Simon Cameron).