To save wetlands, Hyderabad needs to improve its drainage system
HYDERABAD: Hyderabad urgently needs to expand and remodel its drainage system. Besides lakes and canals, wetlands and watersheds play a vital role in absorbing excess rainfall, but regrettably, rapid urbanisation in the twin cities has resulted in the loss of a large portion of the wetlands, according to a Niti Aayog report.
The major findings of the study are that city of Hyderabad as well as Telangana do not have disaster management plans. They are not fully utilising the doppler radar, which can give advance and precise warnings. It recommended that the focus should on disaster response, even while allowing unplanned growth.
Niti Aayog’s “Report of the Committee Constituted for Formulation of Strategy for Flood Management Works in Entire Country” has an exclusive chapter on the Hyderabad floods-2020. An analysis by the Centre for Science and Environment in 2016 revealed that 3,245 hectares of water bodies were lost in Hyderabad between 1989 and 2001, the report said.
In the long run, the effects of flooding due to deluges can only be mitigated if urban planners take into account the hydro-geology of cities and ensure that construction, development and land occupation do not take place in a way that reduces the area of wetlands, the report concluded.
The engineering solutions like linking all the 185 tanks in and around Hyderabad city with modern technology to divert flow of water during deluge, coupled with measures to 50 control flood (rainwater) flow by restoring nalas and removing encroachments would help prevent flooding and inundation.
Delineate nalas, drains
One major suggestion made by report is that nalas, drains and watercourses should be clearly delineated and boundaries fixed while planning new developments.
Overflowing lakes led to maximum damage during floods, says report
During last year’s unprecedented rains and floods in Hyderabad, much of the damage was caused by the overflowing of lakes, in particular the Hussainsagar in the heart of the city and the breaching of stormwater drains, according to Niti Aayog’s ‘Report of the Committee Constituted for Formulation of Strategy for Flood Management Works in Entire Country’.
The report identified construction over lake beds and encroachments of drainage channels as some of the problems that have exacerbated flooding and inundation in the city.
The report recommends that an underground drainage system should be constructed to flush rainwater from any place, whether it is at a high or low elevation, till the final place of discharge, like the Musi river in Hyderabad’s case.
According to estimates, in the last few decades, water bodies have drastically come down from one lakh to 185 within the Greater Hyderabad Capital Region.
Of the 185 lakes, the surplus weirs and courses are completely closed for 75 lakes. These lakes used to work as flood sink of the city. In absence of these, city is more vulnerable to any natural disaster
On October 14, 2020, after a night-long rain, the daily rainfall recorded at the weather monitoring station of the IMD was 19.2 cm. The water drowned the roads and inundated homes worth crores in upmarket localities like Manikonda, Gachibowli, Rajendranagar and Madhapur in the western part of the city.
As per the GHMC data, parts of the Nadeem Colony abutting Shah Hatim Talab had water rise to 12 feet after the downpour on October 13. Devi Nagar and Chudi Bazaar colonies in Goshamahal saw the water rise to 10 feet. Similar were the scenes in several other colonies like Hafiz Baba Nagar, Al Jubail Colony, Ghazi-e-Millat Colony, Chandrayangutta, Ghouse Nagar, Moin Bagh, Edi Bazar, Talab Katta and Riyasat Nagar in the Old City area. All these localities witnessed water rise to four feet. Close to two dozen colonies around LB Nagar too faced a similar fate.
Thirty-three lives were lost in the city, with the GHMC estimating that at least 37,409 families were affected. The Municipal Administration ministry pegged the city’s losses at Rs 670 crore.