The large steel water tank west of the San Jose Market Street station was a prominent feature of photographs and the Sanborn maps. (Because they were originally designed for fire insurance underwriters, fire protection details were much more important than shape of buildings or locations of tracks). The tank resembles the one currently near Diridon station. Either both were built from standard Southern Pacific plans, or perhaps the tank was moved when the Market Street station and yard were shut down.

This SP-style water tank was built to match the water tank at San Jose's Market Street station. The tank is a Rix Products 24 foot diameter tank (with only three of the four courses used); the girders are Central Valley bridge girders. The tank floor and supports is styrene sheet, strip, and I-beams.