GUWAHATI, April 7 - Preparedness holds the key to mitigating the damages and minimising the suffering of the people during natural disasters and the Assam State Disaster Management Authority (ASDMA) has prepared a detailed report with suggestions to mitigate the damages in Guwahati city in such a situation.
A report of ASDMA pointed out that Kamrup (Metro) district falls under earthquake zone-V and a series of measures need to be taken to deal with any eventuality in case of a major earthquake striking the city. The report suggested a host of measures to mitigate the damages in case of a major earthquake striking the city, which include, implementation of building bye-laws for new construction in various areas, retrofitting of weak structures, relocation of the people settled in steep slopes of the hills and near the river banks, assessment of the lifeline buildings and strengthening the same if required, etc. The report further said the public utility buildings should be located in stable areas or on stiff soils.
The report pointed out that floods in Kamrup (Metro) district are inevitable, considering the topography and the river system. What is required is a system of adjustment with floods, so that minimum damages are caused. The objective of flood mitigation is to control changes in the volume of run-off (flash floods), peak stage of the flood, time of rise and duration of floodwater and location of flooding. The main causes of floods in Kamrup (Metro) district are obstruction in drainage system due to heavy rainfall, increase in siltation resulting in rise in riverbeds due to erosion in the catchment areas, poor natural drainage system, unplanned development of city, etc.
The flood mitigation measures should be oriented to take proper care of these problems and thus will automatically reduce the impact of flood in the district. The various measures adopted for flood mitigation may be categorised in two groups � structural and non-structural. The structural measures suggested in the report include construction of embankments and floodwalls along the river bank and improvement of the channel, construction of drainage system in the city, diversion of flood water, location of new facilities, particularly community facilities such as schools, hospitals and other important infrastructure away from flood-prone areas, reforestation of hilly terrain around the city, construction of retaining wall at the landslide-prone areas, etc.
The report also suggested a host of non-structural measures including strict law enforcement and eviction drives, cleaning of drains at regular intervals, awareness drive among the communities towards garbage disposal, collection of daily rainfall data, flood forecasting and warning, etc. The report said a detailed flood map should be prepared and the pattern of floods should be analysed and a plantation drive should also be launched to check soil erosion.
Guwahati city is usually hit by cyclonic storm before the onset of monsoon, causing widespread damages. The report said to mitigate the damages caused by cyclonic storms, planting of trees, which can act as windbreaks, can be taken up and a mass awareness programme should be launched to educate the people about the steps need to be taken during a major storm. Meteorological data should be compiled for storm forecasting and a regulation should be brought to restrict installation of mobile phone towers in residential areas.
Landslide has turned into a major issue in the slopes of the hills around the city, causing damage to life and property and the incidents of landslides have increased in recent years. The report pointed out that landslide is caused by poor soil conditions, geomorphic phenomena, natural physical forces, improper land use pattern and quite often due to heavy spells of rainfall coupled with impeded drainage.
The chief migration measures need to be adopted including correction of drainage systems in the landslide- prone areas by maintenance of natural drainage channels, both micro and macro in vulnerable slopes, regulation of land use pattern, forestation of areas occupied by degraded vegetation, relocation of settlements that are in the landslide-prone areas, construction of gabion structure in important areas, creation of awareness among local people by the district disaster management authority, etc.