Conference program and abstracts - Coastal-Change.Org

Hazard Line Mapping Of Mahadi Delta, Odisha Using
Remote Sensing and Gis
Sukanya R V 1 , Mary Divya 2 , Purvaja Ramachandran 2 , Natarajan T 2 ,
Ramesh R 2*
1
Institute for Ocean Management, Anna University
2
National Centre for Sustainable Coastal Management
*
Corresponding author; rramesh_au@yahoo.com
ABSTRACT
It is estimated that one third of the world’s population are living in the
coastline and their livelihood depends on the resources available from it.
Mahanadi Delta in India is a coastal region located in the state of Odisha.
Mahanadi Delta in India is formed by the network of three major rivers,
Mahanadi, Brahmani and Baitarini draining to Bay of Bengal. The delta
covers a coastline length of 200km, which stretches from south near
Chilika lake to north up to Dhamra river. The population density is high in
the upper part of Mahanadi Delta and gradually declines towards the
coast. Compared to west coast of India east coast is more prone to
cyclones. When compared to other eastern coastal states in India Odisha
is the worst affected state with highest number of cyclonic storms per year
crossing its coast.
The various hazards affecting the coastline of Mahanadi Delta are
erosion, accretion, cyclones, storm surge and extreme events like tsunami.
These hazards lead to severe loss of human life, damage to properties
and to ecosystem. In order to safe guard the people and their properties,
hazard prone areas should be demarcated. A newly adopted method is
based on mapping a composite hazard line considering all the hazards
such as shoreline change, storm surges, cyclones, tsunamis and high tide
line in an integrated way. This hazard line will act as a precautionary
boundary and assist protection and development activities in the
earmarked zone.
The two main components of composite hazard line are shoreline
mapping and flood line mapping (includes: highest high tide level, storm
surges and cyclones).
The data for shoreline will be taken from the past 50yr and will predict for
future 50yr using Linear Regression Method (LRR). For flood line mapping,
the Highest High Tide Level will be found out by using any statistical
method. The maximum values of storm surges will also be taken from past
years data and will be marked on DEM. By connecting the positive value
(maximum value) of shoreline and flood line we will get the hazard line.
Then land use for that area will be carried out and that will tell us what are
the areas and activities that will be affected in the near future.
This study directly supports the Integrated Coastal Zone Management
(ICZM) Plan of Odisha state through the identification and assessment of
coastal hazards and integrating the same to arrive at the composite
hazard line which will help the administrators in effective management of
the coastal zone.
The Fourth IGCP 588: PREPARING FOR COASTAL CHANGE 11