International Journal of Engineering Research & Technology (IJERT) ISSN: 2278-0181 Vol. 3 Issue 9, September- 2014 Flood Hazard Zonation Mapping using Geoinformatics Technology; Bennihalla Basin, Gadag and Dharwad District, Karnataka, India C. M. Noor Mansoor, L. Mahesh Bilwa Basavaraj Hutti Department of Earth Science, University of Mysore SME (Geoscience), Application Software Manasagangotri, Mysore – 570006 L&T Technology Services, Mysore – 570018 Abstract – Flood is an unpredictable and unexpected Basavaraj Hutti and Nijagunappa R; Venkata B. G. and phenomenon occurring from time to time in river basins and Rajiv Sinha has tried to identify areas of risk and prioritize natural drainage systems, which not only damages the lives, their mitigation or response efforts in the natural disaster natural resources and environment, but also causes loss of hazard areas in the Ghatapraba river basin, north Karnataka, economy and health. Using modern technique it is essential for India [4] and Kosi river basin, north Bihar, India [11] in a GIS proper understanding, utilization and management of this precious natural resource. With the advent of powerful and environment. The primary data used for this study were high-speed personal computers, efficient techniques for flood obtained from the digital remote sensing satellite imagery hazard have evolved, of which Geoinformatics technology IRS-1D, LISS III for the study area. The primary decision includes RS (Remote Sensing), GIS (Geographic Information factors considered in this study are geomorphic features, System) and GPS (Global Positioning System) are of great elevation, vegetation, land cover, distance to active channels, significance. In the present study, an attempt has been made to and population density. They have prepared flood hazard delineate flood hazard prone areas in the Bennihalla basin, index. This study formulates an efficient methodology to Gadag and Dharwad district of Karnataka, using accurately delineate the flood hazard areas in the lower Kosi Geoinformatics technology. The thematic layers considered in river basin, north Bihar, India [11]. This study represents this study are lithology, landform, drainage density, recharge, soil, land slope and surface water body, which were prepared some exploratory steps towards developing a new using the satellite data, toposheets, google Earth imagery and methodology for inexpensive, easily read, rapidly accessible conventional data. All these themes and their individual featuresIJERT charts and maps of flood hazard based on morphological, were then assigned weights according to their relativeIJERT topographical, demographical related data. importance in flood occurrence and the corresponding Geoinformatics techniques in flood hazard management in normalized weights were obtained based on number of causative north Indian. As data management and map representations factors including annual rainfall, size of basin, side slopes of tools of GIS helps in exploring new potions its integration basin, gradient of river and stream, drainage density, type of with remote sensing images, enhance the ability for preparing soil, land use & land cover, communication line and flood hazard map and forecasting. The restraints like infrastructures. The population densities were considered for rating the degree of hazard and risk. The thematic layers were Geoinformatics technological knowledge requirements, finally integrated using Auto Desk MAP and MapInfo GIS hardware and software requirements, thus GIS can be very software to flood hazard zonation map of the study area. Thus, useful to minimize flood hazard [2] [8] [9]. different flood hazard zonations were identified, namely ‘high’, Natural resources and hazard mapping which has vital ‘moderate’ and ‘low’. Finally, it is concluded that the component for appropriate land use planning in disaster prone Geoinformatics technology is very resourceful and useful tool areas. It creates easily read, rapidly accessible charts and maps for the flood hazard zonation mapping. which facilitates the administrators and planners to identify areas of risk and prioritize their mitigation or response efforts. Keywords - Flood; Geoinformatics; Drainage; Basin; Rainfall An efficient methodology is used to accurately delineate the decision making areas in the Ghatapraba basin [3]. I. INTRODUCTION However it is essentially a natural phenomenon, Floods are considered as recurrent phenomenon in many overexploitation of natural resources by man increases disaster parts of the India, causing loss of lives, public property and rate year by year [5]. Realizing that its actual and potential bringing inexpressible sadness to the people, especially those consequences are serious and will increase every year, the in the rural areas. There is also a larger economic impact, as government, instead of focusing on relief action as before, set they derail economic activities, thus affecting growth of the up a plan for preventing and /or mitigating this disaster. This country. The government has allocated at outlay of XII five paper presents the study of flood hazard zonation mapping year (2012-2017) plan, ` 57,575.00 crores for the country and procedures for Bennihalla basin, Gagad and Dharwad districts for Karnataka ` 15,000.00 crores for relief measures and other of Karnataka, India [6] [7]. disaster action [1]. IJERTV3IS090683 www.ijert.org 750 (This work is licensed under a Creative Commons Attribution 4.0 International License.) International Journal of Engineering Research & Technology (IJERT) ISSN: 2278-0181 Vol. 3 Issue 9, September- 2014 The research work has been initiated to understand the general topography, nature of soil and type of vegetation in III. MATERIAL AND METHODOLOGY the study area. Demarcate the area of vulnerability and appreciate the effect of resultant flood, to prepare a flood The following materials are used in study area: hazard zonation map through Geoinformatics technology. To Satellite images (IRS-1D, LISS-III) demarcate the river overflow and breaches that lead to free Google Earth images flow of water into the rural as well as urban areas and Topographic (map scale) damages caused to men and materials using GPS and integrate Thematic maps (soil, LU/LC, geology, drainage with RS-GIS softwares. To design a flood zonation map using network, slop, DEM, contours, etc.) the Geoinformatics and spatial technology and suggest a flood Hydrogeological data and maps control and disaster reduction model taking all the detrimental Garmin GPS - eTREX indicators for flood situation, which can reduce the flood Geoinformatics softwares (MapInfo, AutoCAD, disaster in the study area. Google Earth, ERDAS) The detailed methodology flow chart to be adopted for the II. STUDY AREA study is given below at “Fig. 2”. The Bennihalla basin is one of the important tributary of Malaprabha river which is main tributary of Krishna river. The investigated area lies in between north latitudes 15°04‟27” and 15°50‟23” and east longitudes between 74°58‟43” to 75°38‟44”. The study area is surrounded by Rona, Gadag and Shirhatti taluks in the east, Dharwad and Hubli taluks in the west. Shiggaon taluka in the south west and Nargund and Parasgad taluk in the north. Navalgund taluk in the Center. The study area falls in the semi-arid region. The physiographical of the study area is characterized by gently undulating terrain with alternating ridges and slope elevation ranges from 600 m above MSL. The climate of the study area is generally pleasant in the entire basin area. April and May are hottest months with average daily maximum temperature of about 38°C and average daily minimum temperature of about 20°C. The southwest monsoon sets in by June and ends by the middle of October. During this period the basin receives above 50% of the annual rainfall and the climate will be generally humid. Geologically, the study area is underlainIJERTIJERT by Dharwar schistose rocks and granitic gneiss. The northeastern part of the study area is occupied by granitic gneiss, which are mainly covered by thick black cotton soil, shales, phyllites and altered grey wackes of schistose rock are covered the rest of the area. The schistose formations strike in NNW-SSE direction and are dip varying from 35° to nearly vertical. Granitic gneiss strike in NNW- SSE direction and is Figure 1: Research methodology flow chart highly weathered. The index map of the sub-basin is shown in IV. Data Analysis and Compilation “Fig. 1”. A. Generation of thematic layers The flooding hazard zones were identified by interpreting in the study area, a multipara metric dataset comprising satellite data, google Earth data and conventional maps including survey of India (SOI) topographic sheets was used. IRS-1D LISS-III data collected from the national remote sensing center (NRSC), Hyderabad, India has been used for the preparation of thematic maps of drainage density and surface water body etc. All the 11 SOI toposheets (D43D1, D43D2, D43D3, D43D4, D43D5, D43D6, D43D8, D43D9, D43D10, D43D11, 48M5 and 48M7) covering the study area at 1:50,000 scales were scanned separately and all the scanned images were rectified and geometrically corrected. These images were then mosaicked to form a single image and transferred into MapInfo software to prepare thematic layers, Figure 2: Index map of Bennihalla basin namely study area boundary and slope. Further the thematic layers of geology and geomorphology were prepared from IJERTV3IS090683 www.ijert.org 751 (This work is licensed under