The single-story brick structure has a projecting entrance pavilion capped with a triangular pediment that is supported by Ionic columns.

Also noteworthy are the corner piers that feature bands of brick squares set into the stone.

[4] In 1977 voters in Waterloo approved a $3,650,000 bond referendum to renovate the city's 1938 post office and federal building to house the library.

The old library building was listed on the National Register of Historic Places in 1983.

This article about a property in Black Hawk County, Iowa on the National Register of Historic Places is a stub.