Salinity Management in Arid Regions - Restorative Redevelopment of Devastated Ecocultural Landscapes - page 425

In another example, Dickey and Madison (2004) worked on a comprehensive salt
management plan for Owens Lake, located just west of Death Valley in California,
a system they refer to as “an environmental problem of epic proportion,” and thus of
relevance to that which has transpired in southern Iraq. Owens Lake is the body of
water that was drained when the city of Los Angeles diverted its river into the L.A.
Aqueduct to use for drinking water. It is now a huge environmental problem: about
260 km 2 of dusty saline desert lake bed without water. The EPA has issued a mandate
to restore the habitat to bring a halt to the dust storms that plague the area from the
mobilization of the soil that was once the bottom of the lake (this soil is not covered
by vegetation due to being very saline and powdery and is thus easily airborne).
CH2MHILL installed new infrastructure to restore the habitat. The first phase
was to plant 52 km 2 of vegetation for dust control by flooding saline and fresher habi-
tats. Meadows were therefore created over a portion of the total barren area which
with time will grow toward complete cover. The second phase involved reflooding.
CH2MHILL diverted water back out of the L.A. Aqueduct and into the former lake
in order to reestablish this habitat. This approach required a high level of infra-
structure in the form of pipelines and hydrological control systems as Dickey and
Madison were trying to minimize the amount of water they used to accomplish the
task. If they had had access to all the water from the aqueduct, the hydrological
management demands would have been much less. In other words, the more habitat
that one attempts to create with the least amount of water, the more management that
will be required.
This case study has potential relevance to the Iraqi marshes. The water that is
diverted into the drained Owens Lake bed is always fresh, but the further out from
the edge where the water is being inputted the greater the evaporation and conse-
quently the higher the salinity of the remaining water. Far out in the middle of the
former lake, the environment is more like seawater and at the far edge most distant
from the inflow there, it is actually a salt sink where CH2MHILL is building a con-
tainment area in which deposited salts can be concentrated by being flushed there
from the rest of the area. Significantly, there are great wildlife habitat benefits in
the entire area, even those of saltwater (Dickey and Madison 2004). And in the area
where salt is being accumulated, U.S. Borax has built a very large salt-mining opera-
tion to remove minerals from the lake bed.
The soils around the Owens Lake area look very similar to the soils in the Iraqi
marshes: windblown sands and silts. The soil in the lakebed is an anoxic black clay
with a strong sulfur smell, and when it dries out it cracks into large blocks of clay
which fill in with windblown sands and silts, a very poor soil structure for surface-
irrigated agriculture (this is similar to the situation described in chapter 6 for the
Hula Swamp area in Galilee). When water is placed on such soil, it almost imme-
diately runs off the nearly watertight clay into the porous sand structure around it,
resulting in a very poor distribution of water and causing problems if one wanted to
establish agriculture (Dickey and Madison 2004).
Green salt grass is used for revegetation in the Owens Lake project due to its high
salt tolerance. About 850 ha are being grown with fairly saline water through subsur-
face drip irrigation which is very efficient in that there is almost no surface evapo-
ration. This technology was used because if the water is not put back into the lake,