‘WAR DIARY. ARMY HEADQUARTERS, INDIA. […] I.E.F. “D”. Volume 14. PART II. (From 16th to 30th September 1915.)’ [‎65r] (134/276)

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(c) A canal to Pao passing roughly midway between Zubair and
Zubair Gate with branches to the Ashar and Abu Eilus
creeks.
(d) A separate canal from the barrage connecting with the Ashar
creek branch of the Eao canal.
(e) A main drain into the north head of the Khor Zuhair or Khor
Abdulla.
Sir W. Willcocks proposed to commence by irrigating an area of 35,000
hectares or about 87,500 acres, constructing the Eao canal of reduced width
as far as the Abu Eilus creek branch. This preliminary is illustrated on
map No. 70 of the portfolio accompanying the report. The report on the
scheme is so lacking in detail and the available information relating to natural
surface and river levels so limited that it is only possible at the present time to
form general opinions on the suitability of the proposals.
3. The first point which strikes one on examination of the level shown on
„ map 76, is that the average natural surface
Regarding working level behind barrage. , P ,-i , , i , ji
level or the tract embraced by the preli
minary scheme is a little over 2 metres above mean sea level (about 2T m. or 7
feet) while Sir W. Willcocks speaks of the tract as lying at an elevation of only
ES metres. It is evident then, if the map levels are correct, that a water level
of 2 metres behind the barrage would not command the tract to be served by
the canals. The adoption of any higher working level would necessitate the
construction of an embankment from the high desert to the Eao canal, near
its head, and, if not over the whole length, along parts of the Shatt-el-Arab
bank between the barrage and the old Euphrates right bank. Moreover, as
Sir W. Willcocks proposed to allow high floods to escape into the Khor-Abdulla
between the Eao canal and the high desert on the south-west, an escape regula
tor would be necessary in the first embankment spoken of in the preceding
paragraph. These works are not mentioned in the report nor included in the
estimates of cost.
4. Sir W. Willcocks makes no definite statement as to the manner in which
his proposed canals would operate. On
page 39 of his report, however, he speaks
The command of the canals.
of covering the plain between the canal and the river with irrigants fed from
both ends, and it would appear from this that he intended to join up the existing
river creeks to the canal branches or distributaries, but only two such connec
tions, one with the Ashar, and one with the Abu Eilus creek, are shown or map
No. 76. It is also evident from Sir W. Willcocks’ remarks on the provision of
tidal sluices at the river ends of the creeks, that he did not intend to adopt^ them
as a feature of his scheme, and no allowance is made for such works in his esti
mates. The supply level in the canals would consequently be subject to the
fluctuation of the river level with the tide and, except in the head reaches, com
mand for flow irrigation could only be obtained during the higher stages of the
tide in the high water season. Conditions would be improved at the extreme
limits of the existing cultivation but nearer the river the benefits derived from
the proposed canals would be very slight indeed. The only records of the river
levels which are available are those provided by the gauge at the present Koyal
Engineer headquarters, which has been regularly observed from January of the
present year to date. These records supply the following information:—
Height of high tide above M. S. L.
Month.
feet.
Metres.
January
February .......
March
April
May ........
June ... . . . . •
July ........
August
September .......
October
November .......
December
5- 28 to 6-61
5‘61 to 7*00
6- 28 to 7'78
6*44 to 8.61
7- 11 to 8.61
6*61 to 8-53
1 5-6 to 7-00
5*28 to 5*78
5-20 to 5-50
5-20 to 5*50
5*28 to 5*78
5 - 28 to 6'61
1-61 to 2-02
1-71 to 2*14
1-92 to 2 , 37
1-97 to 2 63
217 to 2-63
2'02 to 2'60
1-71 to 2*14
1-62 to 1-76
1‘59 to 1'68
1-59 to 1-68
1*62 to 1-76
1-62 to 2-02