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WEEKLY NEWSLETTER
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Iraq
Index
Irrigation canal south of Baghdad
Courtesy Ronald L. Kuipers
Iraq has more water than most Middle Eastern nations, which
led to the establishment of one of the world's earliest and most
advanced civilizations. Strong, centralized governments--a
phenomenon known as "hydraulic despotism"--emerged because of the
need for organization and for technology in order to exploit the
Tigris and Euphrates rivers. Archaeologists believe that the high
point in the development of the irrigation system occurred about
500 A.D., when a network of irrigation canals permitted
widespread cultivation that made the river basin into a regional
granary
(see Ancient Mesopotamia
, ch. 1). Having been poorly
maintained, the irrigation and drainage canals had deteriorated
badly by the twelfth and thirteenth centuries, when the Mongols
destroyed what remained of the system
(see The Mongol Invasion
, ch. 1).
About one-fifth of Iraq's territory consists of farmland.
About half of this total cultivated area is in the northeastern
plains and mountain valleys, where sufficient rain falls to
sustain agriculture. The remainder of the cultivated land is in
the valleys of the Euphrates and Tigris rivers, which receive
scant rainfall and rely instead on water from the rivers. Both
rivers are fed by snowpack and rainfall in eastern Turkey and in
northwest Iran. The rivers' discharge peaks in March and in May,
too late for winter crops and too early for summer crops. The
flow of the rivers varies considerably every year. Destructive
flooding, particularly of the Tigris, is not uncommon, and some
scholars have placed numerous great flood legends, including the
biblical story of Noah and the ark, in this area. Conversely,
years of low flow make irrigation and agriculture difficult.
Not until the twentieth century did Iraq make a concerted
effort to restore its irrigation and drainage network and to
control seasonal flooding. Various regimes constructed several
large dams and river control projects, rehabilitated old canals,
and built new irrigation systems. Barrages were constructed on
both the Tigris and the Euphrates to channel water into natural
depressions so that floods could be controlled. It was also hoped
that the water could be used for irrigation after the rivers
peaked in the spring, but the combination of high evaporation
from the reservoirs and the absorption of salt residues in the
depressions made some of the water too brackish for agricultural
use. Some dams that created large reservoirs were built in the
valleys of tributaries of the Tigris, a measure that diminished
spring flooding and evened out the supply of water over the
cropping season. When the Euphrates was flowing at an
exceptionally low level in 1984, the government was able to
release water stored in reservoirs to sustain farmers.
In 1988 barrages or dam reservoirs existed at Samarra, Dukan,
Darband, and Khan on the Tigris and Habbaniyah on the Euphrates.
Two new dams on the Tigris at Mosul and Al Hadithah, named
respectively the Saddam and Al Qadisiyah, were on the verge of
completion in 1988. Furthermore, a Chinese-Brazilian joint
venture was constructing a US$2 billion dam on the Great Zab
River, a Tigris tributary in northeastern Iraq. Additional dams
were planned for Badush and Fathah, both on the Tigris. In
Hindiyah on the Euphrates and in Ash Shinafiyah on the Euphrates,
Chinese contractors were building a series of barrages.
Geographic factors contributed to Iraq's water problems. Like
all rivers, the Tigris and the Euphrates carry large amounts of
silt downstream. This silt is deposited in river channels, in
canals, and on the flood plains. In Iraq, the soil has a high
saline content. As the water table rises through flooding or
through irrigation, salt rises into the topsoil, rendering
agricultural land sterile. In addition, the alluvial silt is
highly saline. Drainage thus becomes very important; however,
Iraq's terrain is very flat. Baghdad, for example, although 550
kilometers from the Persian Gulf, is only 34 meters above sea
level. This slight gradient makes the plains susceptible to
flooding and, although it facilitates irrigation, it also hampers
drainage. The flat terrain also provides relatively few sites for
dams. Most important, Iraq lies downstream from both Syria and
Turkey on the Euphrates River and downstream from Turkey on the
Tigris River. In the early 1970s, both Syria and Turkey completed
large dams on the Euphrates and filled vast reservoirs. Iraqi
officials protested the sharp decrease in the river's flow,
claiming that irrigated areas along the Euphrates in Iraq dropped
from 136,000 hectares to 10,000 hectares from 1974 to 1975.
Despite cordial relations between Iraq and Turkey in the late
1980s, the issue of water allocation continued to cause friction
between the two governments. In 1986 Turkey completed tunnels to
divert an estimated one-fifth of the water from the Euphrates
into the Atatürk Dam reservoir. The Turkish government reassured
Iraq that in the long run downstream flows would revert to
normal. Iraqi protests were muted, because Iraq did not yet
exploit Euphrates River water fully for irrigation, and the
government did not wish to complicate its relationship with
Turkey in the midst of the Iran-Iraq War.
Data as of May 1988
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