New GIS warning system saves Chittagong from landslides
Daina Maliat, Chittagong Community Manager
Chittagong, December 4 2015
Global warming has led to the alteration of the sand quality in the Chittagong hills – an area long prone to landslides. Global climate change adds to Chittagong’s natural disasters, and puts its citizens at great risk. Since the birth of industrialization, emission of carbon dioxide gas has increased, confining heat in the Earth’s atmosphere. Excessive heat causes increasing evaporation of water from Bangladesh’s uncountable lakes, ponds and rivers, as well as the surrounding sea. Increasing hill cutting also causes significant negative impact on the rise of landslides in Chittagong city. Landslide damages property and most severely effects the poor inhabitants of Chittagong city living on the Motijhorna, Batali Hill, Golpahar and the countless other hills of Bayezid Bostami. It destructs both the climate and vulnerable minority of hills of Chittagong Metropolitan Area (CMA).
Landslide warnings were generally imparted through loud speakers for a few hours during floods or heavy rains. Due to the loud sound of rainfall and the time limitation, they had negligible significance. To address the issue, Bangladesh University of Engineering and Technology (BUET) established a project based on Web Geographic Information System (GIS) in 2014 to develop the landslide information system with the help of the Japan Institute of Disaster Prevention (JIDPUS). The administration for the project is the International Service for Integrated Mountain Development (ICIMOD) under the SEVIR-Himalayan initiative.
The dynamic Web GIS-based early warning system project hosts the early warning system of possible landslides of Chittagong city on its website. Collections of rainfall predictions are stored first. According to the rainfall estimation, the website sends warnings of landslides five days before the probable catastrophe to the registered subscribers. The site also records precipitation data for the last 30 days using maps. User-friendly reports on slope stability, rainfall pattern analysis, soil investigation, web GIS warnings and community vulnerability are also stored in the site. Chittagong City Corporation, the Department of Fire Service and the Department of Environment Chittagong are subscribers to the site; they are also the primary rapid rescuers for any landslide that takes place in the metro area.
The field study of the project figured out that victims of regular landslides are migrants who come from other cities in the country. They settle in the city, nurturing the hope of finding better jobs and shelter. But the reality of expensive housing costs transforms their living standard. Consequently, they start living in the informal and unstable settlements of the hills that Chittagong has in plenty. The BUET-JIDPUS early warning system for landslides allows authorities to reach out to vulnerable communities living on the CMA hills.
Initiatives such as GIS-based warning system should be encouraged and implemented more to develop the landslide situation of CMA, its marginalized urban community, and the environment.