'Handbook of Mesopotamia. Vol. I. 1918' [‎155] (164/568)

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IRRIGATION OF IRAK 155
very easily have the most serious effect on cultivation in another;
or the improvement of a navigation channel may threaten with ruin
the rice-fields and date-gardens in the neighbourhood. And if the
irrigation of Irak is to be developed in the future on a great scale,
these difficulties would not disappear with the prevention of wasteful
spills. According to the calculations of Sir William Willcocks,
the amount of water brought down by the Tigris and Euphrates (as
measured in northern Irak at Baghdad, Hit, and the Hindiyeh
Barrage) will permit the irrigation of about 7,400,000 acres of wheat,
barley, and other winter crops, and in summer of about 990,000 acres
of rice, and about 3,100,000 acres of millet, sesame, and cotton.
Thus far less than the whole area of cultivable soil in Irak could be
adequately supplied from the Euphrates and Tigris. The low-season
supply might indeed, in the opinion of Sir William Willcocks, be
largely increased by the construction of storage reservoirs in northern
Irak which should husband the surplus flood-water of the rivers.
At any rate, without such reservoirs developed irrigation from the
Tigris and Euphrates upstream of Kut el-Amara and Diwanlyeh
would prevent the Shatt el-Arab from receiving any low-supply
water and would ruin the Basra date-groves. Moreover, if upper
Mesopotamia were extensively irrigated, Irak would feel the conse
quences. 'Heavy irrigation works carried out on the upper
Euphrates and its tributaries the Belikh and Khabur upstream of
Anah . . . would deprive the lower Euphrates of the whole of its
low supply ; while similar works carried out on the upper Tigris and
its tributaries the two Zabs in the neighbourhood of Mosul would
seriously reduce the low supply of the lower Tigris.' Further, the
adjustment of the claims of irrigation to those of navigation would
continue to present difficulties. Thus, according to Sir William
Willcocks, the use of Tigris water for the irrigation of the Shatt
el-Gharaf area would make the river below Kut el-Amara un-
navigable in the low-water season. It appears indeed that the
irrigation of Irak might be carried far enough to make the inland
waterways of the country useless except for small-boat traffic.
The population of Irak is not large enough to make financially
profitable the immediate execution of great irrigation works planned
# on a comprehensive scale. The supply of labour seems to be not
g much in excess of what is needed by the present cultivated area, and
no great increase can be expected from purely Arab immigration.
Something may be done to raise the productive power of the in-
5: habitants by the establishment of law and order, the supplying of
f greater incentives to industry, the introduction of machinery, and
,jl other improvements in agricultural methods. But in any case for
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