‘WAR DIARY. ARMY HEADQUARTERS, INDIA. […] I.E.F. “D”. Volume 14. PART II. (From 16th to 30th September 1915.)’ [‎67r] (138/276)

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7. The following procedure for
Suggested programme of operations.
the development of the desert tract is
recommended if it is decided to under
take it:—
(i) Improve the irrigation of the existing cultivated area by building
automatic tidal sluices of cheap construction near the river ends
of the creeps, which would open when the level of the tideway
rose above retained creek level.
(ii) Extend some of the existing creeks into the desert to bring more
land under cultivation.
(Hi) Construct the Euphrates barrage and supply canal, linking up
existing systems of supply channels and connect the automatic
tidal sluices into controllable regulating sluices, when the
advisability of incurring the extra expenditure arises.
8. The tidal sluices would be built about ^ mile from the mouth of the
Details of proposals for improvement of existing creeks, all existing irrigants taking out
cultivation. of the creeks below the sluice site being
closed off from the creek and connected to the nearest one taking out above
the sluice. By this means large boats could enter the creeks as far as the
sluices, to lie up for repairs. Small boats or ballums could pass through the
sluices when they were open as the velocity of flow would be small with a sluice
of sufficient waterway. If the necessity were felt, however, boat locks could be
constructed in the Ashar Khandak and possibly one or two of the other princi
pal creeks, and the channel dredged from the sluice site to the mouth to permit
of boats entering the creeks at all stages of the tide. The sluices would be built
with masonry abutments, piers and floor and provided with simple swing gates
hinged at top and bottom. The provision of these sluices would vastly improve
the conditions under which cultivation is carried on at present. The irrigants
would receive a better supply and owing to the water surface being retained
continuously at a level only a little below high tide in the river the average
height of lift on to the fields or gardens would be greatly reduced. In order to
avoid a high lift the cultivators must, at present, do their watering at or near
the period of high tide, but the installation of the sluices would render the
whole day available for the task. The average water level in the creeks and
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irrigants, inside the sluices allowing for leakage and withdrawals for irrigation
may be assumed to be, at the outside, one foot below high tide level, although
the difference during neap tides would be less than during springs. On this
assumption the figures of the table in paragraph 4 show that the maximum
amount of lift necessary to irrigate land at 7 feet above mean sea level
would be about 2f feet, from August to January. At spring tides the maxi
mum lift would be about 2^ feet, in September and October only. The existing
creeks between the Khora creek and Gurmat Ali are, on the average, about
fth of a mile apart, but the existence of the tide sluices would permit of the
main irrigating channels being placed at less frequent intervals, and as stated
in paragraph 6 it would be unnecessary to provide all the existing creeks with
sluices. Eor want of detailed surveys, it is not possible, at the present time, to
propose the sites for sluices below the Khora creek. Between the Khora creek
and Gurmat Ali, however, sluices might be constructed in the Khora,
Khandak, Bubat, Jubela and Abusabar creeks The Ashar creek might be left
as it is at present, to begin with, its irrigants closed off from the creek and
supplied from the Khora and Khandal creeks. The other intermediate creeks
could be closed by earth bunds ^ mile from their mouths and their irrigants
connected up with the Bubat, Jubela and other creeks provided with sluices,
those irrigants taking out below the bunds being closed off from the creeks.
These proposals are tentative merely, detailed survey being necessary to deter
mine the best arrangement.
9. As need arose the system just described could be extended to bring
more land under cultivation, by excava-
Extensions of system into desert. ^ runnillg approximately parallel
and at right angles to the river about miles apart connected with those creeks
possessing tidal sluices. Unless the desert spill from the Euphrates swamps
is closed off (as recommended in another Beport) the new area brought under
cultivation would require a new protective embankment to prevent inundation
from the desert spills in years of high river supply, but the cost of this would
be only a small proportion of the cost of the new canal system. In . years of
high flood a drainage system would be required to prevent waterlogging, since
the crops would be flooded with seepage water if the supply level in the canals
remained, as in the present year, above natural surface level for any length
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