It is worth noting that the water level of Brahmaputra River during the entire period of flooding from the 26th June 2014 onwards was well below the Danger Level, thereby inferring that the phenomenon has been solely on account of water-logging engendered by that inadequate natural drainage.

In addition to other factors, the inadequate natural drainage has been due to excessive siltation, deposition of solid wastes, and encroachments of portions of the 4 primary river channels within the city of Gauhati [viz. Bharalu, Mora Bharalu, Basistha and Bahini] and the 5 notified water-bodies of the city [viz. Borsola, Sarusola, Silsako, Bondajan and Deepor Beel]. The phenomenon has resulted in clogging the free flow of storm water and truncating the carrying capacity of the natural channels concerned as well as the natural water-bodies – which used to serve as storage/ detention ponds of excess storm water till they are drained out in due course.

Therefore, the ongoing operation was undertaken to clean and clear the drainage channels and water-bodies concerned of silt, solid waste and encroachment. This included dredging of the channels and water-bodies, as well as eviction of encroachments of Govt. land reserved for such natural channels and water-bodies.

Q2. Which are the areas identified for carrying out the eviction drive?

Ans: The areas identified for the eviction drive are the 4 natural channels/ rivers within Gauhati city and its vicinity which are used for storm-water drainage [i.e. Bharalu, Mora Bharalu, Basistha and Bahini], as well as the 5 notified water-bodies under Gauhati Waterbodies (Preservation and Conservation) Act 2008 [out of which Silsako Beel was targeted in the first phase].

Q3. How much area has been reclaimed so far? How do you propose to prevent re-encroachment of reclaimed area?

Ans: The area reclaimed so far are as follows:
(a) 25 Bighas 2 Kathas 10 Lessas in Bharalu River;
(b) 48 Bighas 1 Katha 10 Lessas in Basistha River;
(c) 21 Bighas in Mora Bharalu River;
(d) 30 Bighas 3 Kathas in Bahini River; and
(e) 81 Bighas in Silsako Beel – i.e.
206 Bighas 2 Kathas in Total.

In order to prevent re-encroachment of the reclaimed area, it has been proposed to dig/ dredge the area deep as well as to fence the area once the reclamation is complete for that portion [i.e. there is no more encroachment left]. Besides, there are proposals to develop the river banks and water-bodies on a sustainable basis, including creation of tourist facilities.

Q4. How many families have been evicted? Is there any plan for rehabilitation of the evicted families?

Ans: During the clearing/ eviction operations, around 2207 structures were removed – including 731 pucca structures, 1083 kutcha structures and 393 walls. There is no report or record of any family being displaced in the process.

However, the Circle Officers under Kamrup Metropolitan District have been directed to enquire and report in this regard. If in case the information of any family being displaced comes to light, appropriate rehabilitation measures shall be taken. There is a plan to construct multi-storeyed housing complexes under Rajiv Awas Yojana and provide low-cost residential apartment to any such family. The Circle Officers concerned have been asked to identify suitable land for that.

Q5. What are the short-term and long-term strategies to address the problem of flash-flood and water-logging in Gauhati city?

Ans: In addition to the clearing and dredging of natural drainage channels and notified water-bodies, including eviction of encroached Govt. land therein; the other short term, mid-term and long-term strategies being conceived to address the problem of flash-flood and water-logging in Gauhati city are as follows.

Short Term:

1) The open drains on both sides of roads shall be cleaned and cleared of siltation and solid garbage dumped therein. The closed drains and the underground drains [beneath the roads or wherever else they exist] shall be opened at the manholes, and similarly cleaned and cleared of siltation and solid garbage present therein. These measures are definitely expected to increase the holding capacity of the drains, and also remove any blockage of water-flow, without any structural intervention which has cost and time involvement.

2) Adequate number of additional sewerage pumps shall be pressed into service in flood-prone areas like Anil Nagar, Nabin Nagar and Pub Sarania areas so as to pump out the excess water into the Bharalu River [or any other river as the case may be]. This measure is expected to reduce the water-logging on account of low elevation and consequent effect of gravity.

3) Resident Welfare Societies shall be set up for the flood-prone areas for ensuring better public co-operation and coordination for reducing the effect of floods. The Action shall be facilitated by the Circle Officers concerned.

While Gauhati receives substantial rainfall (average rainfall for Kamrup is 1600 mm) during monsoon, it lacks a scientific storm-water drainage system and rain-water discharge is highly inadequate.

Mid Term:

1) System shall be devised for regular cleaning of drains by GMC and PWD (Roads). Silt traps shall be set up at strategic places to effectively take out the silt and other solid garbage from the storm-water, and get them removed manually every now and then.

2) Wherein no removable slabs are present in the drains concerned, or the man-holes are too far apart to be effective; roads are to be dug up at the sides to expose the underground drains, and then cleaned and de-silted. Removable slabs/ man-holes shall be inserted therein after that.

3) Damaged drains shall be repaired and re-constructed in a systematic manner. The Action shall be taken by the department maintaining the drains concerned – GMC/ PWD (Roads).

4) Connectivity of all the drains to the outfalls on the natural drainage channels with proper gradient shall be studied and reviewed. In case there is any lack of link somewhere, the linkage shall be established in order to ensure free flow of water out of the drains. Besides, in case there is gradient mismatch, sewerage pumps shall be pressed into service to ensure unhindered flow of water in that section. While the study shall be initiated by GMDA, corrective action shall be taken by the department maintaining the drains concerned – GMC/ PWD (Roads).

5) Steps shall be taken to divert storm-water of at least some areas of Gauhati [e.g. Chandmari] away from the Anil Nagar/ Nabin Nagar areas. Such steps shall involve no major structural change, and shall include measures like effecting alternate connectivity of such storm water – e.g. Noonmati Drainage Project.

Long Term:

1) Comprehensive storm-water drainage plan for the city, that has been prepared by the Tahal Consultancy Group, shall be examined in detail for the points of objection raised by MoUD through another Consultancy Group engaged for that purpose. After that, further evaluation with proper ground surveys by the in-house engineers of GMDA and technical experts like IIT professors and consultants may be done if required. Based on that, an effective Urban Drainage Plan shall be evolved.

2) Sewerage system shall be completely separated from the storm-water drainage system. Besides, steps shall be undertaken to remove the solid waste from the storm water drains.

3) Storm-waters from the Meghalaya hills in the South shall be diverted away from the City along a specially created channel along the National Highway 37 to discharge into the Khonajan rivulet bypassing Deepor Beel, for ultimately discharging into the Brahmaputra.

The long term measures shall be initiated under the aegis of GMDA, and effected with the coordination of all the concerned departments and agencies.