A five-hour drive from the Black Rock Desert is Mono Lake, a still-existing salt lake. Here, the Sierra Nevadas slope down into the Basin and Range at border between Yosemite National Park and the Inyo National Forest. Highway 120, the Tioga Pass, curves out of the mountains into the dormant volcanic basin that holds Mono Lake.
Five years ago, I lived in a settlement on the western border of Yosemite, El Portal. When the Tioga Pass was not blocked by snow, I would often drive two hours through the high country and Tuolumne Meadows to Mono Lake.
Mono Lake is ringed by groves of towering calcium carbonate deposits called tufas. Tufas form when carbonate ions precipitate out of water, merging with calcium to form calcium carbonate, or calcite. They're common in bodies of water close to geothermal activities. Lake-based tufas, lacustrine tufas, rarely take on the columnar form found at Mono Lake
Tufas grow underwater, but they are visible at Mono Lake because Los Angeles began siphoning water from the lake's tributaries in the 1940s. This caused the lake's water level to fall dramatically, revealing many tufas in the years that followed.
The ecosystem collapsed, and conservationists began a long battle to stop the drainage; a compromise was reached in the 1970s. Los Angeles still exports water, but the lake must stay at 6377 feet above sea level.
Below 6377 feet, the salinity of the lake's water becomes too high to support the small lifeforms in the lake: brine shrimp, alkali flies. The islands where rare migratory birds find safe nesting spots grow land-bridges that allow predators access. The air quality plummets. As of April 2016, the water level was at 6378.11 feet.
Much like sand dunes, tufas will precipitate around any foreign object in the water. Dead fish, tiny snail shells, mosses, algae, beer cans, pencils. The tufas at Mono Lake quickly subsume these objects, recording not only the fall of the water level, but also what was left behind with its recession. Matter out of place.