'IRAQ AND THE PERSIAN GULF' [‎34r] (72/862)

DESCRIPTION OF THE LAND 35
water. Babylon had long been replaced by capitals on the Tigris; it
was forsaken and forgotten, and its river-bed was occupied by a
large canal, the Nahr Sura. By the tenth century this had already be
come broader than the western channel, and when in 1102 Hilla was
built on its western bank the town quickly grew to importance. By
the end of the twelfth century this eastern branch was again con
sidered the main channel of the Euphrates and it remained so for
600 years, pouring its surplus waters by many distributaries into the
Great Swamp. The western branch gradually dwindled and eventu
ally silted up, until at the end of the seventeenth century it became
necessary to excavate a new canal to take its place in order to carry
water to the holy city of Najaf, an act of piety financed by an Indian
Moslem. Meanwhile the large canals from the Euphrates to the
Tigris were silting up and much more water passed down the
Euphrates. The bed of the Great Swamp was also being slowly
raised. The effect of closing the Isa (Saqlawiya) canal by Midhat
Pasha An Ottoman title used after the names of certain provincial governors, high-ranking officials and military commanders. in 1870 was felt almost at once. Year by year the canal to
Najaf took more and more flood water, and within ten years it had
broadened to become the main channel. Land along the Hilla branch
began to go out of cultivation from lack of water for irrigation, and
distress became so acute that efforts had to be made by the con
struction of a weir on the western channel to divert water back to the
eastern. Unfortunately this step was taken too late and by 1909 the
Hilla branch was only discharging 300 cubic metres per second com
pared with 2,000 which it had taken forty years before, and with
2,500 carried in 1909 by the Hindiya branch.
On the advice of Sir William Willcocks, who was called to advise
the Turkish authorities, this weir was replaced by the Hindiya bar
rage, completed a short distance higher up the river just before the
last war, and remodelled since. Details are given in Chapter X.
The chief effect has been to restore an ample supply throughout the
year to the eastern channel, which is now regulated and known as
the Hilla canal. In addition, two other irrigation canals make use
of the barrage: the Georgiya (Jarjiya) on the left bank and the Bam
Hasan on the right, and the flow of the older Husainiya on the right
bank is also regulated (fig. 8). The districts irrigated by these canals
are shown on fig. 20. For further details see p. 437.
The following table gives the approximate average disposal of
water supplies calculated for a normal September month (low-water
season) before the Abu Ghuraib canal was regulated (1937). The
figures are expressed in percentages of the total supply available at Hit: