Flood Potential Analysis (Fpan) Using Geo-Spatial Data in Penampang Area, Sabah
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Malaysian Journal Geosciences (MJG) 1(1) (2017) 01-06 ISSN: 2521-0920 (Print) ISSN: 2521-0602 (Online) Contents List available at RAZI Publishing Malaysian Journal of Geosciences Journal Homepage:http://www.razipublishing.com/journals/malaysian-journal-of-geosciences-mjg/ https://doi.org/10.26480/mjg.01.2017.01.06 Flood Potential Analysis (FPAn) using Geo-Spatial Data in Penampang area, Sabah Rodeano Roslee*1, Felix Tongkul1, Norbert Simon2 & Mohd. Norazman Norhisham1 1Geology Programme, Faculty of Science and Natural Resources, University Malaysia Sabah,UMS Road, 88400 Kota Kinabalu, Sabah, Malaysia 2Department of Geology, Faculty of Science and Technology, University Kebangsaan Malaysia, 43600 Bangi, Selangor This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. ARTICLE DETAILS ABSTRACT Article history: recorded especially in Penampang area, Sabah (e.g. July 1999; October 2010; April 2013; October & December Received 22 January 2017 Flooding is one of the major natural disasters in Sabah, Malaysia. Several recent cases of catastrophic flooding were Accepted 03 February 2017 Available online 05 February 2017 has affected 40,000 people from 70 villages. The main objective of this study are to analysis the Flood Potential Level2014). (FPL) Heavy in monsoonthe study rainfallarea. In hasthis triggered study, eigth floods (8) parametersand caused weregreat considereddamage in Penampangin relation to area. the causativeThe 2014 factors floods Keywords: Flood Potential Analysis (FPAn) to flooding, which are: rainfall, slope gradient, elevation, drainage density, landuse, soil textures, slope curvatures Multi-Criteria Evaluation (MCE) Sabah, and flow accumulation. Flood Potential Analysis (FPAn) map were produced based on the data collected from the Malaysia field survey, laboratory analysis, high resolution digital radar images (IFSAR) acquisation, and secondary data. FPL were defined using Multi Criteria Evaluation (MCE) technique integrated with GIS software. The information from this paper can contribute to better management of flood disaster in this study area. 1. Introduction The Penampang District of Sabah, East Malaysia (Fig. 1) is subjected to fromdevelopment rural development pressure as and the cultivation urban centre of rice of paddy Kota toKinabalu intensive expands urban developmentonto the Sungai presents Moyog afloodplain. range of Thesocial subsequent and environmental transition of issues. land useOf particular concern to the area are the issues associated with flooding. In 2014 from October 7 to October 10, Penampang suffered its worse flood ever, since the last big flood in 1991 (Figs. 2 & 3). According to the District Officer of Penampang as many as 40,000 people from 70 villages were inaffected Penampang by the occurredflood. The on flood September coincided 2007 with and continuous May 2013, heavy affecting rainfall several due villagesto typhoon (Fig. Phanfone 3). and typhoon Vongfong. Another recent flood disaster Daerah Penampang) Figure 2: Some cases of flash flood in Penampang, Sabah (Sources: Pejabat Figure 3: Daily recorded rainfall of Babagon Agriculture Station from year August 2002 – May 2015 (Sources: Department of Drainage and Irrigation). The main objectives of this study are to analysis the Flood Potential Level (FPL) in the study area. It is hopes that the outcomes from this study can be an important reference document for the local authority and other relevant Figure 1: Location of the study area agencies for the purpose of urban planning and flood mitigation. An ad hoc, or reactive, approach to floodplain management has previously *Corresponding Author been standard practice. Insufficient control over floodplain development Email Address: [email protected] (Rodeano Roslee) practice has led to a worsening of the flood problem. Until recently, floodplain management has only involved structural approaches to modifying flood behaviour. However, without planning, the structural flood modification only compensates for the poor development practice by restoring the flood behaviour to pre-development conditions. Ultimately, there is no net benefit. 1 Mohd. Norazman Norhisham / Mal. J. Geo 1(1) (2017) 01-06 Cite this article as: Flood Potential Analysis (FPAn) using Geo-Spatial Data in Penampang area, Sabah. Rodeano Roslee, Felix Tongkul, Norbert Simon & Rodeano Roslee, Felix Tongkul, Norbert Simon & Mohd. Norazman Norhisham / Malaysian Journal of Geosciences 1(1) (2017) 01–06 2 capable of converting subjective assessments of relative importance into a An ad hoc, or reactive, approach to floodplain management has previously decision making process known as Analytical Hierarchy Process (AHP) is been standard practice. Insufficient control over floodplain development pair-wise comparisons as an input and produces the relative weights as practice has led to a worsening of the flood problem. Until recently, output.linear set Further of weights. the AHP The provides criterion a mathematicalpair-wise comparison method of matrix translating takes thisthe floodplain management has only involved structural approaches to modifying flood behaviour. However, without planning, the structural of the reason that individual judgments will never be agreed perfectly, the flood modification only compensates for the poor development practice by degreematrix intoof consistency a vector of achieved relative inweights the ratings for the is criteria.measured Moreover, by a Consistency because restoring the flood behaviour to pre-development conditions. Ultimately, there is no net benefit. 1 appliedIn the recent using years,probabilistic there have methods.5-9 been many In differentstudies on ways, flood hydrological susceptibility/ and Ratio (CR) indicating the probability that the matrix ratings were randomly stochastichazard/risk rainfall mapping method using hasGIS alsotools2-4 been andemployed many ofin theseother studiesareas.10-16 have shouldgenerated. be revised, The rule-of-thumb in other words is that it is a notCR lessacceptable. than or equal41-42 to 0.10 signifies an acceptable reciprocal matrix, and ratio over 0.10 implies that the matrix studies.17-29 2.3 Flood Potential Analysis (FPAn) Likewise neural network methods have been applied in various case The initial step in Phase III is the delineation and conversion processes of data from the radar images (IFSAR). Phase III also covers the integration Determining the flood susceptible/vulnerable areas is very important between criteria weights and maps, producing a Flood Potential Analysis to decision makers for planning and management of activities. Decision (FPAn) using spatial analyst, which determine the Flood Potential Level making is actually a choice or selection of alternative course of action in (FPL). ofmany different fields, criteria.both the Allsocial these and criteria natural need sciences. to be The evaluated inevitable for problems decision All of the thematic maps produced were analyzed through the spatial analysis.30-34in these fields necessitated For instance, a Multidetailed Criteria analysis Evaluation considering (MCE) a large methods number has are related geographically.35-36 Geographic Information System (GIS) analyst technique (raster calculator) based on Eq. (1) for LSL estimation been applied in several studies since 80% of data used by decision makers usingand classification a grid base. (Tab. 1). The FPL calculation was carried out through a combination of input parametric maps in Eq. (1) with the GIS operations setprovides of criteria more withand betterthe overlay information process,37-38 for decision and makingthe multi-criteria situations. [(32.53*Rainfall) + (22.74*Drainage Density) + (15.84*Flow Accumulation) decisionIt allows analysisthe decision within makers GIS is usedto identify to develop a list, and meeting evaluate a predefinedalternative + (11.08*Landuse) + (7.19*Elevation) + (4.89*Slope Gradient) + (3.35*Soil plans that may facilitate compromise among interested parties.39 2. Materials and Method Textures) + (2.38*Slope Curvatures)] (1) three (3) main phases involved, namely: a) Phase I: Selection andFig. 4evaluation shows the of frameworkcriteria; b)model Phase used II: inMulti-Criteria this study. ThereEvaluation are (MCE); and c) Phase III: Flood Potential Analysis (FPAn). Criteria Evaluation (MCE) for Flood Potential Analysis (FPAn) Figure 4: Framework model of integrating spatial analysis with Multi- 2.1 Selection and evaluation of criteria The main purpose in Phase I are database development. Firstly, soil samples were collected from the field will be analyzed their types in accordance with BS1377-1990. The next step is secondary data compilation and literature review. Lastly observation of Flood Hazard Identification (FHI) parameters was conducted through the fieldwork study (Fig. 4) In Phase II, the choice of criterions that has a spatial reference is an important 2.2 Multi-Criteria Evaluation (MCE) technique inand the profound study area. step Eigthin Multi-Criteria factors are Evaluationconsidered (MCE) in relation technique. to the Hence, causative the factors,criteria considerwhich are in thisrainfall, study slope is based gradient, on their topography, significance drainage in causing density, flood landuse, soil textures, slope curvatures and flow accumulation (Fig. 4). Several questionnaires were distributed among experts in hydrology