The editorial published in The Assam Tribune on March 28 last under the title �City Drainage� has encouraged me to reiterate a few of my past observations and also to offer additional suggestions for consideration of the authorities concerned in particular and the citizens of Guwahati city in general.
In view of the flood situation in Guwahati city during the 90s, I had suggested in the Dainik Asom in 1996 to augment the drainage system in order to provide an alternative system for quick drainage of flood waters from the northern part of the city, leaving the other areas, including the saucer-shaped part between the RG Baruah Road and Bhangagarh, upto the Bharalu stream. It was suggested to prioritise development of the drain on the northern part of the railway line connecting the river Brahmaputra at Uzanbazar by constructing a drain on the abandoned land which was previously occupied by a railway track.
Further, construction of two additional drains accross the hilly areas at Noonmati and another towards the eastern end with provision of a sluice gate were part of the proposal. It was subsequently suggested to provide low-lift high-volume axial flow pumps with automatic pumping system for quick disposal of water during the Brahmaputra in spate, i.e., flowing above the danger level. I still consider the proposal as relevant.
I remember having cautioned in the aforesaid write-up that the flood problem might also occur in the southern part of the city, although it was free from such a situation. It was therefore suggested to develop a drainage system in the areas, i.e., providing a drain connecting the Deepor Beel. The flood situation in the area during 2002 amply proved my concern.
However, due to rapid development of the peripheral areas of greater Guwahati city, I had also suggested to consider a drainage channel to release the flood water beyond the Gopinath Bordoloi International Airport via gravity flow. Construction of such a drain in Dibrugarh city during the 60s, after providing a dyke to save the town, proved effective. The outlet of the Bharalu into the Brahmaputra towards the eastern direction was also discussed, whereas the river flows from east to west. This situation hinders outflow from the tributary.
Concern was voiced regarding delay in construction of silt traps because the editorial indentified that the high amount of silt carried from the surrounding hills was an important factor in creating congestion on the drainage system. In this connection I felt it necessary to instal such a system in the foothillsof Nizarapara and Chandmari with a provision of collecting the trapped silt downstream at a convenient place on trial-cum-demonstration basis under the Soil Conservation Department. Though there are several organisations capable of undertaking such a step, but no one came forward to take the post-operative responsibility. Therefore, it is hoped that this aspect will be adequately taken care of by the authority concerned.
The editorial under reference criticised the faulty implementation of different drainage projects in the city by wasting crores of rupees during one-and-a-half decade. I was surprised to find a project at Senduri Ali area on the RG Baruah Road to drain out water into the Bharalu. I doubted its utility, as the hume pipes would be subsequently clogged. It was proved within two years.
The reason for raising this issue now is to find a means to overcome such wasteful expenditure. Such project unnecessarily cause inconvenience to the public during the construction period. Moreover, hume pipe drains are installed in the developed countries for disposal of treated sewage. I was therefore surprised as to why the elite residents of the locality did not object to undertaking such a useless project. The editorial bitterly criticised such projects.
Moreover, Guwahati city is widely considered as a hub of repectable bureaucrats, technocrats and intellectuals of the region. Can they not mobilise public opinion to shelve such projects right at the initial stage? However, we should accept the compulsion of members of the elected bodies because of their political affiliation resulting in mismanagement in implementation of such development projects. Therefore, a society named Water Resource Development and Management may be constituted after considering that �water is life�, by the conscious citizens. On successful functioning of such a forum, it may be replicated in other towns too.
Lastly, I wish to suggest that the Guwahati Development Authority undertake a project on rain water harvesting to strengthen the sinking ground water reservoir as well as to minimise the surface run-off, which overloads the drainage system. Because of Guwahati city being gradually converted into a concrete city, the problem of drainage has been aggravated manifold. Moreover, indiscriminate installation of deep tubewells has depleted the ground water reserves. Therefore, replenishing the ground water is very essential, where shallow underground rocky geo-psysiographic situation is in existence. Thus, the concept of Ground Water Banking should be developed by offering premium to individuals and builders for diverting storm water into deep infiltration zones.
Efforts should also be made to regularly monitor inflow and outflow of water, including silt load through the Water Resource Department for future planning.
The editorial specifically mentioned about the systematic destruction of forest cover in the surrounding hills, resulting in poor retention capacity of the soil. Consequently, not only does a greater volume of water roll down from the hills to the plains within a short span of time, but it also causes largescale damage. It also fails to replenish the ground water acquifiers for want of subsurface inflow of water into the valley region.
Under such a situation, it is essential to develop infrastructure in terms of rain water harvesting in order to replenish ground water resources both in individual and collective capacity. It is also a hidden means for outflow of drainage water.
Further, it is essential to keep in mind the adverse effects of climate change in aggravating the drainage problem. The prediction about higher amount of rainfall with increase in the intensity and frequency of storms, but decrease in rainy days has already been experienced. Therefore, holistic and non-conventional planning is required for preparation of flood management project by overhauling the existing drainage projects as expresed in the editorial, for which a movement of the socially conscious citizens is considered essential.