Inconsistency, or A Conspiracy? - The Ganga: Water Use in the Indian Subcontinent - page 112

by upper riparian states without augmenting the flow by some other means, but these
fell on deaf ears of powers-that-be in New Delhi. Within 2 years of the commission-
ing of the barrage, the River Bhagirathi, being deprived of a regular discharge of
40,000 cusecs, went lean and thin. Respective governments imposed no restrictions
on reckless withdrawal of water from the Ganga, nor were any augmentation plan
initiated. The Union government gave no guarantee of minimum flow of 40,000
cusecs into the River Bhagirathi either. The discharge from the barrage decreased
day by day in the Ganga, as the Bhagirathi-Hooghly was continuously deprived of
the minimum wanted 40,000 cusecs. The treaty, signed between Dhaka and New
Delhi, further aggravated the situation.
The 3,000 million rupee project (in 1985 prices) comprising two barrages (at
Farakka and Jangipur), one head and other regulators, feeder canal, guide and afflux
bund s, cross-drainage works, bridges etc. were designed to enable the river receive,
even in the driest season, at least 40,000 cusecs. The designs accorded with past
hydrological data and detailed investigations, which assumed that at least around
55,000 cusecs of water would be available in the leanest season in the Ganga and
after meeting the requirement of Calcutta port and of the stream from Jangipur to
the sea to be resuscitated, 15,000 cusecs could flow to Bangladesh (East Pakistan
before 1972). The statements by Dr. K. L. Rao meant that this huge expendi-
ture yielded only partial result and had adverse effects on the navigation in the
Bhagirathi-Hooghly and on Calcutta port.
Effects of Reduced Discharge
The effects of the reduced discharge from Farakka in the driest months from March
to May, from 40,000 to 25,000, to 20,000 and even 15,000 cusecs were studied by
Calcutta Port Commissioners, Government of West Bengal and others before the
commissioning of the project. They predicted that
a) About 80% of silt in the port area and the upper reaches of the river owing to
upward movement of sand from the sea occur from March to May. Reduction of
discharge in this period of high tides would continue to push the sand and silt
upstream, albeit with less intensity but their volume, thus deposited, would be in
excess of that which move to the sea in other months of the year. The cumulative
effects of this would continue but at a slower rate and eventual closure of the
waterway for deep-sea navigation would be delayed but not averted.
b) Discharge of less than 40,000 cusecs would also reduce, though slowly, the total
volume of accretion. Hence, compared to the pre-barrage condition, the zone of
most significant accretion which was above Calcutta port before 1975 would
shift downward and accumulate near the port area, disturbing the navigation
channel, mooring facilities, jetties etc.
c) When the zone of maximum siltation shifts downstream below Calcutta, fre-
quency of bore tides would increase in this reach and render navigation
extremely hazardous.