Various locations in Greater Hyderabad Municipal Corporation (GHMC) received very heavy to extremely heavy rains that caused flooding on several roads and low-lying areas of the city.
IMD Hyderabad meteorologist B Raja Rao said: “In the limits of GHMC so far, the record rainfall is 24 centimeters at Begumpet in Hyderabad in August 2000 when the city was flooded. Now in the last 24 hours until At 5:00 AM, about 29.8 centimeters of rain has been recorded.Recorded at the GHMC boundaries in Hayatnagar. On the outskirts of the town of Ghatkeswar about 32.3 centimeters have been recorded. More than 21 centimeters of 35 places in the city have been recorded. This is Hyderabad’s all-time record rainfall. ”
Floods are not new in Hyderabad
The Musi River was the cause of frequent flooding in the city of Hyderabad. According to historical records, the flood occurred eleven times in Hyderabad since 1572AD.
Reasons for floods in hyderabad
Hyderabad is a catchment system. The western edge is in the Godavari river basin (from Kukatpally, Ramchandrapuram to Gachibowli). To the east, it is in the Krishna river basin. Also, Hyderabad is in the Deccan region, which has a chaotic drainage pattern – the water here does not flow in one direction as the slope is in multiple directions. These tanks served agricultural purposes and the surrounding areas were “local protected catchment areas.” In the last 40 years an entire city has been added to this agrarian imprint. Roads, which have rigid boundaries, have been built around “fluid” bodies of water, with no buffer zones. Necklace Road is a spectacular example of that. Both the command area and the tank beach have developed buildings.
One of our biggest failures is waste management, as all industrial waste and sewage is dumped into the lakes, the accumulated waste has now affected the holding capacity of the lakes, vertically. So the original ‘tank full limit’ of our water bodies / lakes is no longer valid.
Kirloskar committee findings after 2000 floods
- More than 2,700 illegal encroachments were found in the city’s nalas, of which 1,400 must be eliminated.
- Nalas will expand to 60 feet at some points and 40-48 feet at others to accommodate higher flows
- The drainage system in Twin City is inadequate; it is designed for only 12mm of rain per hour.
- Abids, Panjagutta, Trimulgherry, Saifabad, Kacheguda, Begumpet, Charminar,
Vanasthalipuram , Uppal, Kukatpally and Madhapur were marked as susceptible to severe waterlogging.
A 2016 report from the Center for Science and Environment (CSE), the State of Urban Water Bodies in India, estimates that in the past 12 years, Hyderabad has lost 3,245 ha of its wetlands. Rapid urbanization is significantly altering natural waterways and watersheds.
Urban stormwater management may not be efficient unless it is managed jointly. A multidimensional approach is necessary to solve this problem. For the present case, some of the management options that must be carried out simultaneously to address the problem are:
- A risk mapping of city areas should be carried out to assess vulnerability, related to urban floods, using GIS technology.
- Limit, reduce and / or mitigate impervious surfaces throughout the watershed by using new engineering techniques such as permeable roads, permeable parking lots should be considered and implemented whenever possible to minimize surface runoff.
- Conserve and protect areas for groundwater recharge. Use joint management to improve groundwater storage: In some cases, diversions of surface water for groundwater infiltration could improve flood management by reducing peak flows.
- Promote groundwater recharge and pollutant attenuation by removing concrete flood control channels and exposing underlying native sediment.
- GHMC / HMWSSB should reconsider its policy of charging the amount for
Rainwater on crops structures while permission to plan is granted. They must maintain this as a checkpoint to deliver the certificate of occupancy.
- The GHMC Urban Planning department must regularly monitor prohibited areas to prevent invasions.
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