Robert Smithson built Spiral Jetty in 1970 in the Great Salt Lake in Utah. It was after a period of drought when the water level was low, but Smithson underestimated how high the waters would rise. Spiral Jetty was only visible for 2 years before becoming submerged for over 30 years. then another drought caused it to slowly reappear, with much excitement from the arterati. However its period of submersion and re-emergence has had consequences.. it was made of black basalt rock, making a particular contrast with the reddish waters caused by salt-tolerant bacteria. When it re-emerged it appeared whitened as it was entirely encrusted with salt, and as the waters have dropped still further visitors have been able to walk between the rings of the jetty. Now there is a huge debate as to whether the structure should be preserved as it originally looked but made higher with added black rock, or should time and water be allowed to mark progress. Smithson spoke about this ambiguously at the time, saying he was in favour of entropy, but also wanted his works to be preserved. As he died only three years after Spiral Jetty was built he cannot consulted now.
Spiral Jetty as it looks now.