Hyderabad: In view of the coming monsoon season, Greater Hyderabad Municipal Corporation (GHMC) has concentrated on improvement of storm water drains in the twin cities limit. GHMC has estimated that the total cost involved in remodeling of major and minor storm water drains and others, would be about Rs 12,000 crore.
In a report to the government, GHMC said about 390 kilometers length of major and 1,000 kilometers length of minor storm water drains have to be remodeled to make Hyderabad a flood resilient city.
In the report submitted to the state government, GHMC said that rapid urbanisation has resulted in increased impermeable surfaces in the form of pavements, roads and built-up areas, thereby reducing the water infiltration and natural storage. Urban flooding is significantly different from rural flooding as urbanisation leads to developed catchments which increases the flood peaks from 1.8 to 8 times and flood volumes by up to 6 times.
Consequently flooding occurs very quickly due to faster flow times, sometimes in a matter of minutes. Due to very strong monsoon, rain intensities of more than 60 mm per hour are becoming common in the recent past, which is one of the major causes of flooding in Hyderabad, resulting in a wide range of secondary impacts ranging from adverse health effects to traffic breakdowns and infrastructure damage. In the report GHMC said that the number of water bodies, once 530 is down to 169 at present in GHMC area.
The GHMC has decided to take up removal of encroachments on Nalas in a big way and for enumeration of encroachments and properties affected under Nala widening, 24 survey teams headed by deputy commissioners of GHMC were constituted.
The GHMC said to make Hyderabad a global and flood resilient city, the restoration of lakes and improvement of storm water drains is necessary. GHMC estimated that the total cost involved in remodeling of major storm water drains of 390 km length and minor storm water drains of 1,000 km length including land acquisition, relief and rehabilitation, utility shifting charges and others, was Rs 12,000 crore.
The GHMC said deepening of the Nalas and raising of walls is not feasible due to hydraulic levels at inlet of Nalas and disposal points of Nalas, which are already governed by the existing ground levels of source and disposal points. The GHMC officials said that the flooding problems cannot be solved unless the total Nalas are widened to its required width all along its length from source to disposal point.
