Kerala is eyeing high-resolution hazard maps for better assessment and identification of vulnerable areas as part of long-term flood management strategies.
The State government has requested the Central Water Commission (CWC) to prepare large-scale, high-resolution hazard maps of flood-prone areas in Kerala based on the conditions set down in the National Disaster Management Plan.
Towards this end, the State has sought an urgent meeting — via videoconference if required, given the COVID-19 situation — of the regional committee for the scientific assessment of flood-prone areas at the earliest.
This panel, constituted by the CWC, last met in July 2015, an official said.
The Water Resources Department placed the State’s requirements before the CWC in a letter last week.
For all river basins
The executive committee of the Kerala State Disaster Management Authority (KSDMA) has concluded that the State is in need of the high-resolution maps for all river basins which provide insights into different recurrence intervals for extreme rainfall events using at least a 20-metre digital elevation model.
According to the National Disaster Management Plan, 2019, national-level research and technical institutions, Ministry of Jal Shakti and the Department of Space are responsible for the preparation of large-scale hazard maps which identify highly vulnerable locations (zoning, mapping and classification of flood-prone areas).
For Kerala, the devastating floods of 2018 and 2019 had revealed the need for accurate data and inputs for crafting long-term management strategies for tackling natural calamities such as floods.
33 types of maps
The higher resolution maps will help the State in the preparation of regional flood plans in the long run.
“As part of preparing disaster management plans for local bodies, the KSDMA had already provided 33 types of maps which were validated and used to mark vulnerable areas. These flood susceptibility maps can be further improved, but for that we need maps with a higher resolution,” a senior official said.
In the aftermath of the 2018 floods, the KSDMA had updated the ‘Orange book of disaster management — Kerala — Standard operating procedures and emergency support functions plan’ and introduced a separate ‘Monsoon preparedness and emergency response plan’.