The owners of the Carson & Colorado railroad were in the transportation business. They built it with the hope that they would be transporting precious metals - gold and silver - and all that was necessary to extract, refine, and sell them...just as they had done with their previous venture, the V & T.

But their timing was awful. They were too late for Cerro Gordo and Darwin and too early for Tonopah and Goldfield. So they had to make do with the common metals and stone they got from the mountains, the produce they got from local ranches and farms, and the minerals they could extract from Owens Lake. In service of the latter they laid claim to 3000 acres around its shores and formed the Inyo Development Company.

But extraction of minerals was no simple matter and its history is initimately connected with the water history of the valley. I found a paper - written by a professional electrical engineer and amateur geologist - which describes the situation better than I ever could so I quote it in its entirety.

A Brief History of Owens Lake Mineral Production

by Walt Margerum ... with corrections in blue by Paul Lamos

Until 1913 when the Los Angeles Aqueduct was opened Owens lake was about 30 feet deep at its deepest point. It had a water source, the Owens River, and several local streams, but no outlet other than evaporation. After the opening of the aqueduct the inflows were all diverted and the lake began to dry up. In the summer of 1922 trona precipitated due to the desiccation caused by the cutoff of the water entering the lake. That winter sodium carbonate, and sodium sulfate also started to precipitate. This caused all the companies operating on the lake to revise their process of recovery.

The Inyo Development Company started commercial production from Owens Lake in 1887 using solar evaporation ponds constructed just north of Keeler. The ponds were filled with lake water, and allowed to evaporate throughout the summer until trona [Na2CO3·NaHCO3·2H2O] formed on the bottom of the ponds. Around October the ponds were drained and the trona was harvested. About 25% to 30% of the dissolved sodium carbonate could be recovered by this means. Some was shipped as trona, and the remainder was heated in ovens to produce soda ash. It was then shipped via the Narrow gauge railroad to market. They also tried unsuccessfully to produce potash around 1916. They continued in operation until 1920 when the lake water became too concentrated for solar evaporation, due to the drying up of the lake after the 1917 completion of the Los Angeles Aqueduct.

Around 1912 The Natural Soda Products Company was formed and started operations south of Keeler. They used solar evaporation to concentrate the water, and then a process that bubbled CO2 through a tower filled with the concentrated lake water. This process recovered 60% to 70% of the dissolved sodium carbonate as sodium bicarbonate. It was then sold either as sodium bicarbonate, or processed into soda ash. They also sold trona from the evaporation ponds. As the lake desiccated they revised their processes, by adding water from wells. After going bankrupt in 1927, they were bought out by the Michigan Alkali Company, later part of the Wyandotte Chemical Corporation. They continued in operation using a process of chilling the brine to obtain sal soda [Na2CO3. 10H2O], but could not stop the formation of sodium sulfate [Na2SO4. 10H2O](this is the formula for mirabilite which is a ten mole sodium sulfate), During this time a flood occurred on the Owens River got into the lake and disrupted their operations. The plant was sold in 1950, and continued in operation until 1952 when it was dismantled. Its location is marked by a large white pile of dead burned lime; either CaO if limestone was used for the source of CO2 or a combination of CaO and MgO if dolomite was used as the source of CO2 , and is now the headquarters of the reclamation project.

The Los Angeles Aqueduct brought the standard guage railroad from Mojave and with it construction of plants on the west side of Owens Lake. The California Alkali Company commenced operations just north of Cartago in 1917 using a process similar to that used by the Natural Soda Products Company.

Both the Natural Soda Products Company, and the California Alkali Company obtained their CO2 from vertical coke fired lime kilns using dolomite from the Western Inyo Mountains, or limestone from Cerro Gordo.

In 1924 the California Alkali Company was acquired by the Inyo Chemical Company who continued to use the bicarbonate process in spite of its decreased efficiency due to the increased concentration of the carbonated due to desiccation, until the plant was closed in 1932 and never reopened. They also recovered a small amount of borax. All that remains is a large waste pile near Cartago.

In 1926 the Kuhnert Syndicate built a pilot modified carbonization plant at Bartlett on the West side of the lake. By 1928 the process was worked out and the Pacific Alkali Company was formed to operate the plant. This plant recovered trona, and also borax. This plant was later purchased by the Columbia-Southern Chemical Corp. a subsidiary of Pittsburgh Plate Glass Co. who modernized the plant and operated it through the 1960’s.

Several companies tried to produce caustic soda (NaOH) in a plant near Bartlett, but were unsuccessful. The last production was in 1928.

In 1947 the Permanente Metals Corporation started a plant between Cartago and Bartlett on the west shore of the lake. Its life was short, and it ceased operations in 1950. All that is left are the concrete foundations.

Today the only operator on the lake is the U.S. Borax plant located north of Cartago. They produce trona for use in borax refining at Boron.