Only a Barrage Can Save! - The Ganga: Water Use in the Indian Subcontinent - page 78

added, the tides were deteriorating the river. If the ebb and flow tides were equal,
they might have, almost continuously and uniformly, scoured and kept a channel
open, for long periods but the flood tide is stronger than the ebb and carries more
silt. At high water, when the flood tide stops, some silt is deposited; the ebb tide
then ran down and scoured out much of the deposited silt. The silt deposited in the
upper reaches was less subject to the scour of the ebb tide than that in the lower
reaches. A river channel, subject only to the action of the tides, tended to silt up
the upper reaches first and then deterioration gradually extended down through the
whole length of the river, becoming more and more evident in the later stages, as the
tidal capacity of the river diminishes more and more.

...

The Hooghly has deterio-
rated perceptively during the last quarter of a century in the upper 50 miles (80 km)
of its tidal length and most, as one would naturally expect, in the first 20 miles
(32 km) below Nadia.

The Hooghly River Commission

The Commission, set up by the Government of India in 1853-1854 and asked to
study the condition of the river, reported that it has deteriorated gradually, owing
to shoaling and contraction of its deep channel from accumulation of silt and that
under the present condition, the deterioration would be progressive. Mr. Piddington,
a member of the Commission, studied the deterioration from a scientific angle. He
recognized the role of the freshets in maintaining the channel and added:

I am of opinion that it is of the highest importance to the future state of navigation of
the river, at least from Calcutta to about Hooghly Point, that the most strenuous endeavours
should be made and every means used and every experiment tried to ensure a copious supply
of water for as many months in the year as possible at the heads and along the courses of
the three main feeders of the Hooghly. By 'three main feeders' he meant the Bhagirathi-
Hooghly, the Bhairab-Jalangi and the Mathabhanga-Churni.

View of H. Leonard

H. Leonard, Superintending Engineer of the Public Works department, asked to
report on the river in 1864, visited major European rivers which were being
improved then. He consulted Sir Charles Hartley, Engineer of the Danube
Commission and submitted a report in June, next year, reviewing the general
hydraulic factors in the maintenance of the Hooghly and the condition of criti-
cal points for navigation. He agreed with the majority of the Commission that it
was difficult to come to any other conclusion than that the Hooghly must deteri-
orate, howsoever slowly, considering the agencies at work on the river. First, the
volume of silt, carried down, every year, by the river must be deposited in, or
about, the debouche, lengthening out the sand heads and thus decreasing the scour-
ing power of the stream. Secondly, there is the constant, though slow, widening
of the lower section of the river, which tends to diminish this power and leave no
room for the channels to change from side to side. Mr. Leonard agreed with the