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Data integration for flood risk analysis by using GIS/RS as tools  Mr. Falak Nawaz Research Associate, National Centre of Excellence in Geology University of Peshawar, Pakistan Tel: 92-091-860822 (R), 0092-91-9216429 (O) Fax: 92-091-9216427 Email: falak63@yahoo.com Mr. Mohammad Shafique World Wilde Life Organization (WWF), Peshawar, Pakistan Introduction The study area is situated in the District Muzaffarabad, which is the capital of Azad Kashmir. The study area is situated at the confluence of river Jhelum and Neelum. It is at situated at a distance of 138 km from Islamabad (Capital of Pakistan). River Neelum is the main contributor of flooding in this area. Other important river of the study area is river Jhelum. Both these rivers meet at Domel in Muzaffarabad (Fig.1). Flood of 1992 has been found to be more severe flood in the in the history of Muzaffarabad, which cause severe damage to economy and number of lives were lost (Table.1). For a number of reasons the most frequent choice should be the protection from the flood by means of physical control of the river but there is also need for a more broader and comprehensive program for managing flood hazard in the study area. Flood protection has been helpful and must be continued side by side other preventive tools like effective planning for the growth of the city, creation of a computerized GIS database for the flood prone area and a detailed flood risk mapping and zonation are required to minimize the harmful affects of flood hazard. Keeping in view the importance of the problem, an intensive study of the problem has been carried out. For this purpose Geographical Information System (GIS) were applied as a tool as a result, detailed mapping were drawn for the flood hazard assessment.  Fig.1: Location of the Study Area Objectives of the Study Following are the main objectives of the study.
Drainage Pattern The Jhelum and Neelum are two rivers, which flow through the district. The Jhelum river, which has its source in the Varing spring in the Anantnag (Islamabad) district of occupied Kashmir. Enters near Chakoti at the confluence of Urusa nala and flows in a southeast to north west directions up to Muzaffarabad where Neelum river joins it. Then after it runs toward south along the border of Azad Kashmir and Pakistan. The Neelum River, which was formerly known as Kishan Ganga has also its source in the occupied Kashmir and enter the district in Athmuqam tehsil and flows through Neelum valley. Climate The climate varies considerably in the north and in the south. The southern part of the district experience warm summer and cold winter whereas in the north summer is cool and winter extremely cold. June, July and August are the hot months. The mean maximum and minimum temperature during the month of July are about 350 and 23OC. respectively. December, January and February are the cold months. The mean maximum and minimum temperatures during the month of January are 16O and 3OC respectively. Average annual precipitation of the district is 1511 millimeters (Table.2). Research Methodology The methodology was adopted in the study according to the objectives of the study, available data and techniques. The flow chart shows the methodology adopted during the this study (Fig. 2); 
 Fig. 2 Methodology used creation of Hazard Map GIS as a Natural Hazard Management Tool Nowadays GIS is emerging as a powerful tool for the assessment of risk and management of Natural Hazards. Due to these techniques, natural hazard mapping can be prepared now to delineate flood prone areas on the map. Such kind of maps will help the civil authorities for quick assessment of potential impact of a natural hazard and initiation of appropriate measures for reducing the impact. Such data will help the planners and decision-makers to take positive and in time steps during pre disaster situation. It will also help them during post disaster activities for the assessment of damages and losses occur due to flooding. Moreover, GIS provides a broad range of tool for determining areas affected by floods or forecasting areas likely to be flooded due to high discharge of the river. With the help of sequential images of certain area, we can find out the behavior of the flood routing and damages. Creation of Hazard Maps For the analysis and creation of maps, researcher used the city guide map, which was purchased from the Survey of Pakistan office. The coordinates of the map were not known but taking control point with the help of Global Positioning System (GPS) on the ground, the required maps were georeferenced. With the help of screen digitising, a segment map of the city has been drawn. A separate label point map by giving unique ID number to each point was prepared. The segments map then was polygonised with the same label point map. Side by side, a separate table was prepared in which four columns were created. One for Land use, age of the buildings, material used for these buildings, vulnerability and number of storeys of the houses. For these columns separate domains were used. After putting all the information carefully, the table has been linked with the base map by using attribute command. Land Use Map Fig. 3 shows different land uses in the study area. It reveals that predominantly residential areas are situated at the riverbank. The map also shows that there is severe lack of land use planning. As in the lower plate, which are the high-class residential area of the Muzaffarabad city, and it is located just at the bank Neelum River. Red fort, which is the cultural heritage of the Muzaffarabad is located just on the Neelum riverbank and was severally damaged by the flood of 1992. In Makri village, the people construct their mud houses there because the land is cheap. Also most of the cantonment area is located just on the riverbank. At Domel the confluence of River Neelum and Jhelum there is high class commercial area like Five Star Hotels are located just on the river bank that are vulnerable to flooding. Some Government offices like the WAPDA (Electricity Department), Officer Club, National Bank are located at the Neelum River bank are also vulnerable to flooding. Critical Facilities Critical facilities like Hospitals, Schools, Colleges, Important offices etc can play very important role during any natural hazard. All such facilities are also needed to be taking care hence these are very expensive places and also in some cases it needs utmost protection for example National Bank, Revenue office have very important and sensitive data. In case of damaging these documents, it can create very serious problems to the civil administration. So it is necessary that such critical facilities should be demarcated on the map separately. Similarly play grounds parks & open spaces even schools and colleges can provide temporary shelter to the stricken families from any natural hazards. But during the selection of such areas it is important to have a proper road link so that in emergency peoples could shifted safely and quickly. In the city, one Hospital, School, College, Cantonment, Neelum Stadium, Income Tax office, National Bank and number of other places situated which can be used as a shelter places during flooding. The map has been drawn by applying the mask command from land use map (Fig. 4).  Fig. 3 (Left): Showing Land use map while Fig. 4 (Right) Critical Facilities Creation of Vulnerability Maps Office of United Nations Development Relief Organization (UNDRO), defines the term vulnerability as: “The degree of loss to a given element or set of elements at risk resulting from the occurrence of a natural phenomenon of a given magnitude. It is expressed on a scale from 0 (no damage) to 1 (total damage)”. Keeping in view the definition of vulnerability, some weight value has been aided to the attribute column like age, material, number of storey and vulnerability. For example those houses which were more old, with double or triple storey houses, with low quality material the dwellers use during the construction of the houses and which are more vulnerable to floods has been given low values like 1, 2 or 3 etc, likewise those houses which are newly constructed, preferably single storey, material which has been used of good quality and which are less vulnerable to flooding has been given high values (10, 9 or 8 etc) in these columns. The values that were given in the attribute columns were calculated with the help of the following formula entered on the main window of ILWIS software. The resultant map, which acquired as a result of this calculation, was a Classified Hazard map (Fig. 5). Hazard =Wlanduse+Wage+Wmaterial+Wvulnerbility+Wstoreys After the calculation based on the above mentioned formula, the researcher got the map which was only indicating the value by clicking on any parcels. Such kind of values makes no meanings for those people who don’t know about the methodology applied, so to make the result more acceptable, a separate domain has been created in which the resultant values were divided into three classes: very high, high, moderate and low hazard areas, for example;
 Fig. 5: Classified Hazard Map produced after Slicing with different domain Findings of the Study Following are the findings of the study, which have been found after the analysis and study of the area;
The following recommendations are suggested. Land use Planning Land use planning can play very important role to reduce the adverse effects of flooding. It is recommended to adopt an appropriate landuse planning in flood prone area. The ideal form of planning would be to evacuate the flood prone completely but practically it is not possible as to involve high costs and some social problem are associated. It is possible to change the functional characteristics of the flood plain area and to apply ban on the future encroachment in the flood prone areas. The ideal application is the zoning control in the flood plains. As suggested by Kates and White in their book in 1961.They put forward a three zone division which are as following.
Hazard Assessment and Risk Mapping In most of the countries, the concerned authorities are preparing risk assessment maps by applying GIS and RS as tools now. In this regard, recently Federal Flood Commission in Pakistan has also prepared GIS based hazard maps by indicating villages, which are prone to flood hazard. It is very much important now to regularly updating and proper maintenance of spatial data. These kinds of maps will help the authorities for quick assessment during pre and post disaster situation. Need of a Computerized GIS Database There is intense need for computerized GIS databases for the study area. Such data will help the planners and decision-makers to take positive and in time steps during pre-disaster situation. It will also help the planners and decision-makers during post-disaster activities for the assessment of damages and losses occurred due to flooding. Trained Personnel There is a need of trained staff to operate GIS database and up-date this data from time to time. Training is advised at these levels;
Acquisition of RS Data from SUPARCO office Acquisition of images especially during any particular flood event from SUPARCO office is very important. It will help the planners and decision-makers to find out the area and villages, which have been affected by flooding. If it is possible then aerial photographs of the flood peak time will further help them to stream line their strategies to mitigate and rehabilitate the flood affectees more efficiently and more quickly. More Space for River Jhelum Near the City On both sides of the river Jhelum, the natural flow of the river has been obstructed by the unplanned construction. It is recommended to give back the original space to the river Jhelum. It is very difficult to implement but there is no way out. Conclusion Flood hazard is destructive and frequently occurring phenomenon in the study area. Due to lack of proper warning information about the flood hazard to the people living in the flood prone area is not communicated effectively. Due to which affectees receive more damages. Due to severe lack of land use planning in the study area, the community build rather rebuild their houses not only close to the river bank. Hazard assessment and risk mapping can prove very useful tool for advance planning, which is totally missing. No importance has been given on this side. Even a computerized record of the data and archive is not available in concerned offices. Although flooding is a natural phenomenon we can not completely stop it but we can minimize its adverse effects by better planning. For reduction of vulnerability in the study area to flood hazard there is urgent need to adopt long-term strategies by skillfully combining the engineering devices with proper planning Acknowledgments The researchers are very thankful to Mr. Zaheer ud Din Qureshi for providing generous help and nice accommodation during our stay in Muzaffarabad city. Also thanks to Ms. Shamoona Naqvi (GIS/RS diploma student) and her parents for providing possible help. Last but not the least, we are thankful to official of land use planning department, Muzaffarabad, who provide maps and necessary information. References
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