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SALTON SEA GENERAL PLAN

Selenium Removal

The current preferred California State plan to mitigate against dust is to build marshes on the south shore of the Salton Sea using river water from the Alamo & New Rivers. If fresh water is used for this, one ends up with cattail marshes which are of no use to fish-eating birds like pelicans, skimmers, terns and cormorants.
Therefore, the plan is to mix Salton Sea water with agricultural return water to produce brackish water. This prevents emergent plants from growing, but the water still supports algae and fish for the birds to feed on. Selenium can be very toxic to fish and particularly birds at extremely low concentrations (5-15 ppb). The selenium concentration increases as it passes up the food chain, from algae to insects to fish to birds. In birds, it leads to gruesome embryonic abnormalities and death.


Working under GELF’s Facility Use Agreement, the Bureau of Reclamation is assisting GELF by testing and validating technologies and equipment used by GELF to remove selenium at the Salton Sea. Particle Adsorption has proved effective for removing selenium at small scale at the Salt River Project in North East Arizona. Reclamation’s Advanced Water Treatment Team in Denver Colorado is validating particle adsorption for removing selenium from the Alamo River.  GELF has proposed using particle adsorption at the Redhill Bay Wetlands restoration project, a 420 acre constructed wetland habitat project.


Brine Degradation

Because the Salton Sea is a terminal lake, increasingly concentrated salts have resulted in a salinity that is currently 50 percent greater than that of the ocean. The increasing salinity and other water quality issues, including temperature extremes, eutrophication, and related anoxia and algal productivity, are adversely influencing the Sea's fish and wildlife resources. Declining inflows in future years will result in collapse of the Salton Sea ecosystem due to increasing salinity and other water quality issues.Tilapia, which is presently the primary forage species for piscivorous (fish-eating) birds at the Salton Sea, may be eliminated when salinity exceeds 60 parts per thousand (ppt).

GELF proposed using a process that transform brine into electricity with little byproduct. The brine degradation system can work in concert with any desalination technology including geothermal desalination. This energy positive system is an essential disposal bioreactor for the desalination brine. On Jan. 3rd, 2017, a team of scientists from three universities met with members of the U.S. Bureau of Reclamation Advanced Water Treatment Laboratory in Denver Colorado, and with Bruce Wilcox the assistant secretary for Salton Sea policy at the California Natural Resources Agency to discuss using this processes for applications at the Salton Sea.

At some point, if the Salton Sea is to maintain life, desalination of the sea must occur. Evaporative desalination is in pilot testing now and the brine is being stored in tanks. The byproduct of desalination, concentrated brine, is removed through a degradation system. The brine power generator is a 4 stage system that degrades brine constituents while simultaneously transforming them into electricity.  Protecting the food of millions of bird species is an important aspect of the Salton Sea Authority. A brine management plan is imperative for the success of any desalination project.

Water Generation

The Salton Sea is expected to fall from 3 to 20 feet in coming years because of water transfers associated with the Quantitative Settlement Agreement and increased water conservation due to changes in agricultural practices. The shoreline is expected recede, exposing up to 77,000 acres that could emit toxic dust particles.  This dust contains arsenic, selenium, chromium, zinc, lead and pesticides, including DDT. These chemicals are expected to attach themselves to the fine particles of sediment when the lake water recedes and could cause respiratory illnesses throughout the region. One way the State of California and the Salton Sea Authority are addressing the toxic dust is through development of wetlands. GELF is introducing a new method of dust mitigation by building a system that transforms biodegradable waste into water, oxygen and electricity. The system is scalable and can produce significant amounts of water. GELF proposes to cover exposed playa area with water generated by the Water Power Generator.