Bay Model!
Recently visited the Bay Model in Sausalito: a physical scale model of San Francisco Bay, the size of two American-football fields, built by the Army Corps of Engineers in 1957.
“The Bay Model was constructed […] to study the circulation and flow characteristics of the water within the San Francisco Bay estuary system and related waterways. The Model was used to reproduce (to the proper scale) the rise and fall of tide, flow and currents of water, mixing of salt and fresh water, and indicates trends in sediment movement. Assessments could be made regarding the impact of human activities such as dredging navigation channels, filling portions of the Bay, diverting water, and introducing wastes and oil spills.” (Quoted from the Bay Model’s Master Plan document, from their website.)
In particular, it was originally constructed to test the viability of the late-1940s Reber Plan: one of several proposals to install dams and turn the Bay into freshwater lakes. The test demonstrated that the Reber Plan wouldn’t work.
The Bay Model’s simulation goes through a full tidal cycle every fifteen minutes.
In 2000, the research group switched over to using a computer model, but the physical model is still available to be visited.
Thanks to Jim M for introducing me to the Bay Model and going there with me!