'Handbook of Mesopotamia. Vol. I. 1918' [‎167] (176/568)

I
IRRIGATION OF IRAK 167
Magil to the Shaaibeh ridge north-west of Zobeir, and from the
Zobeir Gate of Basra to the high ground near Zobeir town. These
bunds have held up the inundations from north and south, but it
seems that the consequent increase of water in the Shatt el-Arab
has done some damage among the date-gardens on the river-bank.)
(d) The country between Beled and Baghdad on the right bank
ot the Tigris was to be watered from the Tigris through the restored
Dujeil, which was to be kept supplied by means of barrages on the
river immediately below the head of the canal (see above, p. 163).
Large canals branching from the Dujeil were to supply the alluvial
lands east and west of it.
The area commanded by these works was to be 170,000 hectares
(419,000 acres). The estimated pr e-war cost of the irrigation works
was JT2,118,240 (£1,906,416); that of the agricultural works was
ill <£T1,700,000 (£1,580,000).
(e) The country along the lower course of the Nahrawan, east of
of the Diyaleh, was to be irrigated, for winter crops only, by Diyaleh
water carried in the Nahrawan.
At present the lower Diyaleh feeds the Khalis system on its right
bank, and the Khorasan, Mahrut, and Beled Ruz canals on its left
bank. Good masonry regulators at the heads of these canals are
needed, as well as regulators for the escapes back into the Diyaleh.
The existing canals appropriate the whole supply of the Diyaleh
in the low-water season, but at other times they leave in the river
enough water to irrigate a considerable area on which winter crops
could be grown. Sir William Willcocks has proposed to turn this
available water into the lower course of the NahrawS-n between Abu
Sifweh and Kut el-Amara. He indicates three possible ways of
doing this:
(i) By a masonry barrage at Abu Sifweh ; but this barrage would
be strained very severely to maintain the level of the water needed
for the canal
(ii) By the construction of a canal taking off from the Diyaleh
under the Jebel Hamrln and carried thence to the lower Nahrawan.
(iii) By the diversion of the main stream of the Diyaleh in the
neighbourhood of the Jebel Hamrln to a line passing east of the Beled
Ruz canal and down the Khor el-Merj and the Khor Suweikiyeh
to the Tigris east of Kut. Part of the Diyaleh waters would then
be allowed to pass down the old bed of the river to Abu Sifweh,
and could there be turned into the Nahrawan by an earthen dam.
The total area to be commanded along the lower Nahrawan is
200,000 hectares (494,000 acres). The cost of the irrigation works
involved in scheme (iii) under pre-war conditions was put at