To sustain the health of the Sea, several challenges must be met:   salinity, nutrients, elevation, and bird disease.   The Salton Sea Restoration Project is addressing each of these through a combination of long term and short term actions.

Salinity

Salinity has been identified as the Number 1 challenge, and has been referred to as the Salton Sea’s “time bomb.”   Salinity levels must be stabilized to preserve the life in the Sea and to buy time to address the Sea’s other challenges.

Most of the water entering the Sea comes from the Colorado River and is salty when it arrives.   The water brings the equivalent of a trainload of salt every day.   Because the Sea has no outlet, the water evaporates, leaving the salt behind to accumulate.   If nothing is done, the salty water will kill the fish and, with them, the birds that depend on the fish for food.   To maintain the Sea at current levels of salinity, several million tons of salt must be removed annually.

The restoration project is testing two methods for removing salt.   The first, solar evaporation ponds, has been used for at least 10,000 years to make salt.   It consists of moving water through a series of shallow ponds to evaporate the water and concentrate the salt, until only solid salt or a very saline brine remains.   A separate disposal site will be needed.

The Imperial Irrigation District has made available an eleven acre site to test a series of ten ponds to establish baseline information on the rate of evaporation, the rate of seepage into the soil, and the characteristics of the remaining salt.   That test is underway. Once authorized and funded, a larger test of up to 1000 acres of ponds will begin.

The second method for removing salt is known as Enhanced Evaporation Systems (EES).   The concept is the same, evaporate the water to concentrate the salt, but the evaporation is enhanced, or sped-up, by spraying the water in a fine mist and capturing the remaining salt.   Several technologies have been developed, machines similar to large snowblowers, tall towers which spray water, etc.  A 700 hour test has shown that, while feasible, the cost of testing an expanded system is not cost-effective at this time.

No matter what system is used, the remaining salt has to be disposed of.   Because salt is cheap to buy, expensive to transport, and the Sea is a long way from potential markets, it is unlikely that it can be marketed commercially.   Some have suggested putting the salt back in the Sea behind dikes to store it.   However, the presence of earthquake faults underlying the Sea means that all the salt removal could be for nothing if a quake hit, the dikes failed and the salt redissolved into the Sea.   Finding sites near the Sea offers the least expensive option for disposal.   Tests are now planned on various disposal options.

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Nutrients

The nature of the Sea is to be eutrophic - full of nutrients.   The nutrients are what support the rich and abundant life in the Sea.   They flow in with the water that comes from urban and agricultural runoff.   The nutrients do not create a known health risk. 

Once in the Sea, some nutrients are continuously recycled, used by living creatures and then returned to the Sea when they die.   Some nutrients precipitate out.   But as with salts, evaporating water in a closed basin concentrates the nutrients which are left behind.  

The Salton Sea is like an underwater tropical rainforest.   “Little critters”, microorganisms of many varieties, abound.   Scientists have found completely new, previously unknown species as well as a vast number of known ones.   They form the basis for the food chain, providing food for fish which in turn are food for birds.

But like everything else, there can be too much of a good thing.   At present levels, algae bloom and die, using up oxygen in the water and causing large fish kills.   Nutrient reduction will be part of stabilizing the Sea.   Studies are currently underway to determine current levels of nutrient inflow, recycling, and precipitation out of the water and into the sediments.  Preliminary findings show that reducing phosphorus inflows may be the most important step in reducing eutrophication.   A project is now in the initial stages to reduce the nutrients that flow into the Sea by treating the water flowing into the Sea with alum or by other means.

Responsibility for regulating inflows rests with state and federal water quality agencies.   The restoration project is examining various methods for removing nutrients, including fish harvesting for animal feed, fish meal or fertilizer.   A modification of state regulations to allow commercial harvesting at the Sea would be needed.

The Authority is presently contracting for the removal of dead fish from the shores and considering on-water recovery during periods of fish die-off.   While the clean-up is primarily for aesthetic reasons, removing the sight and smell of dead fish has a side benefit of lessening the recycling of nutrients.   Authority staff are exploring the possibilities of converting the dead fish into fertilizer.

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Elevation

Because the Sea is a closed basin, increases or reductions in inflows can dramatically change the elevation of the Sea and either flood or strand seaside residents.   After increases in agricultural return flows and back to back 100 year floods in the '70s and another flood in the '80s, the elevation of the Sea increased to current levels.   Reservation land, seaside homes and marinas, boat facilities, parks and agricultural fields were flooded.   Since then, the current quantity of inflows is enough to stabilize the elevation at its present level.

Now, the pressure on California to restrict its use of Colorado River water to its legal entitlement is forcing farmers and urban water users to conserve, and agricultural districts to consider transferring water to growing cities.   The Restoration Project is assessing what the impact will be from reduced flows to the Sea.   It is also examining options for maintaining current elevation levels even if inflows are reduced.

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Bird Disease

Bird die-offs at the Sea from bird diseases occur at generally the same rate as bird die-offs elsewhere.   Birds are like people, anytime numbers and proximity increase, the likelihood of one sick bird infecting others increases as well.   Most of the die-offs have been from known causes: bird diseases such as avian botulism, Newcastle’s disease, or avian cholera.

There are two reasons why it is vital to try to prevent or limit bird diseases at the Sea.   First, the Sea hosts very large proportions of some bird populations.   An epidemic could decimate those species.   For example, in some years 90 percent of eared grebes use the Sea.   In 1992, 150,000 eared grebes died out of a total population of about 750,000 birds.

Second, many endangered, threatened or sensitive species of birds use the Sea and a die-off could put their populations at risk.   In 1996, 1100 brown pelicans died from avian botulism, the largest known loss of an endangered species.   The Salton Sea Authority has funded a wildlife technician who works cooperatively with staff from the Sonny Bono Salton Sea National Wildlife Refuge (U.S. Fish and Wildlife Service) to monitor birds daily and collect birds that appear ill.

An "emergency room" is available at the refuge to treat birds immediately and to send them to nearby bird hospitals if needed.   The early detection and treatment has restricted the spread of disease and almost two-thirds of the sick birds have been rehabilitated and released.

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