Solar Evaporation Ponds at
the Salton Sea for Salinity
Control
Process, Progress, and
Opportunities
Agrarian Research and
Management Company
under contract to
Solar Evaporation Ponds offer a
salinity control method that is:

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Technically
feasible
Economically
viable
Environmentally
friendly
Existing solar salt ponds in
operation for over 100 years
Evaluation of
suitable area for
siting of solar
evaporation
ponds at the
Salton Sea based
on soil seepage,
slope, and
considerations of
land use
Large ponds take in brine and expose
it to sunlight and evaporation
The evaporation ponds concentrate salt and evaporate water
until only solid and bittern salts remain
Water volume
Concentration
Water from Salton Sea
Concentrator
Pond 1
Concentrator
Pond 2
Concentrator
Pond 3
Solid
Salt
Pond
Bittern
salts
Pumps and gravity move the water
Pilot Demonstration Project at Niland
How Evaporation Ponds can Control
Salinity at the Salton Sea
Inflow to Sea: water + salt
No outflow: salt accumulates
Salton Sea
Water + salt removed to evaporation ponds:
Water evaporates
Salt remains on shore
Possible Conceptual Design for
Solar Evaporation Ponds
Salt is stored where it is deposited, and the
pond levees are built higher to accommodate it
Bittern salts may not be solid, but
they make up a very small volume
Bittern
ponds
Progress at the Pilot Pond Project
Evaporation rates of
brine
Salt formation in
the crystallizer
ponds
Collection of brine and salt
chemistry data
Evaluation of seepage through
berms as well as floor of ponds
Solar Salt Ponds and Wildlife
Wildlife Refuges in Salt Pond Habitat
San Diego National
Wildlife Refuge with
Western Salt
CDF&G Wildlife
Refuge Napa, State
management alone
Don Edwards
NWF San
Francisco Bay
with Cargill Salt
shallow saline water for
feeding
saline
water
produces
rich food
source
nesting habitat
Berms and islands create safe
resting places
Crystallizers are a refuge for resting
Lands affected
would be adjacent
to, or close to, the
existing Sea
margins
Potential accumulation of
contaminants in concentrators and
solid salt deposits
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
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Selenium
Pesticides
Metal residues
Other agricultural chemicals such as
fertilizers
Preliminary indications are that these
issues will not prove to be problems for
solar evaporation pond implementation
Advantages and Benefits


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
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Solar ponds most economical
Solar salt ponds in use for over 100 years
Solar salt ponds can be managed for habitat
“Win – Win” situation for salinity control and
habitat
Alternatives available to deal with loss of
water in the Sea
Economic and environmental benefits to area
Future of Solar Evaporation
Salt Ponds at the Salton Sea

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Salinity problem must be addressed in
order to maintain habitat values
Assessment of environmental concerns
is in progress
The most viable and beneficial solution
available to solve the salinity problem
CaSo4
Salts
produced
from a typical
brine
Ton NaCl / ac/in
NaCl
MgCl
NaSO4
KCl
Results from the brine
chemistry investigations
25
20
15
10
5
0
Magnesium
Series2
Series2
4
Series3
2
Series4
0
Series3
Series4
B2
2
B2
7
B3
9
BR
Series1
6
Sample
B2
4
B2
1
B3
5
Series1
Wt %
8
B2
2
B2
7
B3
9
B2
4
B2
1
B3
5
Wt %
Chloride
Sample
Calcium
Sulfate
Sample
Series4
Sample
B3
5
B3
5
B2
1
B2
4
B3
9
B2
7
0
Series3
B2
1
h-P
B2
4
0.02
Series2
B3
9
AR
Series1
B2
7
0.04
12
10
8
6
4
2
0
B2
2
BR
Wt %
0.06
B2
2
Wt %
0.08