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 Atatόrk 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
Data as of May 1988