The two upper stories rest on a ground floor with slightly battered walls and a concrete surface that is rusticated to simulate sandstone.

The Oak Street entrance has double-glazed doors with a transom set in a segmental-arched opening with a scored fan pattern above mimicking a masonry arch construction.

A long flight of granite steps with a solid railing leads to the main entrance on Santa Clara Avenue.

On the principal Santa Clara Avenue facade, the recessed central portion has the entrance in the center of three monumental, round-headed brick arches embellished with continuous architrave molding.

The structure initially featured a two-story clock tower situated prominently above the central section of the main facade.

This tower boasted round-arched windows, shallow balconies on the upper story, and a hipped roof adorned with a bracketed cornice.

Notably, the City of Alameda achieved a pioneering status in California, being the first and the second in the United States to operate its own power plant, inaugurated in 1886.

Richardson's influential design for the Allegheny County Courthouse (1884–1890) served as a model, and the Alameda City Hall subtly mirrors its general format.

Noteworthy is the fact that Percy & Hamilton, the architectural firm behind the Alameda City Hall, contributed to approximately 200 buildings in the San Francisco Bay Area, including notable projects like the Stanford University Art Museum and the Children's Playhouse in Golden Gate Park.