Underground Estuary (2009)

Exploratorium, San Francisco, CA

8" x 72", Steel, water filled acrylic cylinder, chart recorder, 25' well

Underground Estuary makes visible tidal fluctuations in sub-surface groundwater levels. Sitting over a 25' well, water in the column moves up and down in synchrony with the groundwater. A mechanical float in the water column drives a drum-type chart recorder plotting a month's worth of groundwater fluctuation.