The Downey Rose Parade float is stored and worked on in an old building on the Rancho Los Amigos south campus. Driving there these past couple of weeks to see the float in progress, I once again noticed the old water tower. It's enclosed in the fenced-off and abandoned section of the campus, in what used to be the Los Angeles County Poor Farm.
The farm was originally created in 1888. It eventually morphed into the Rancho Los Amigos Hospital, until this section was abandoned in the 1980s. For a fairly comprehensive historical write-up about the farm, see Ranch of the Friends: The Extraordinary Evolution of the L.A. County Poor Farm.