10.2190/ES.32.3.b 5616741T881XP646 2 Floodplain Mapping and Visualization for Flood Risk Assessment and Decision Support in Sarawak Kanan River 201 219 20110304 20110304 20110304 20110304 5616741T881XP646.pdf http://baywood.metapress.com/link.asp?target=contribution&id=5616741T881XP646 3 Frederik Josep Putuhena Darrien Yau Seng Mah Sai Hin Lai Universiti Malaysia Sarawak Universiti Sains Malaysia Sarawak Kanan River is one of the tidal rivers frequently affected by flood in Sarawak, Malaysia. Over the years, physical development has been concentrated in the middle valley town of Bau, where the center of administration and commerce for the district is located. The town of Bau and surrounding areas is a well known flood-prone area, for being geographically located in the floodplain of Sarawak Kanan River. Major floods of February 2003 and January 2004 had Bau and surrounding areas flood-stricken. The area has little hydrological information to ponder with, thus indicating a need of a flood visualization model to have a better explanation of the flooding scenarios in the floodplain areas. For this purpose, the flooding of Sarawak Kanan River was modeled using the InfoWorks RS one-dimensional hydrodynamic model. The inputs consist of observed discharge hydrographs of upstream Buan Bidi sub-catchment and lumped synthetic discharge hydrographs of ungauged sub-basins. Observed stage hydrographs measured at Siniawan were used as downstream input. This article outlined the methodology for flood mapping and visualization to enable flood risk assessment and decision support modeling for future development in floodplain protection and control. The model was capable of providing an acceptable estimate of flood depths with a correlation coefficient of 0.83. Boutayeb, N. E., El-Badraoui, M. H., & Mahfoud, J. (1995). <i>Hydraulic modeling of the Ourika Valley.</i> Proceedings of 2nd DHI Software User Conference, June 9-11. Available from: http://www.dhi.dk/usercon/abstr/22.doc [Accessed January 19, 2004]. <a target="_blank" href='http://www.dhi.dk/usercon/abstr/22.doc'>http://www.dhi.dk/usercon/abstr/22.doc</a> Chadwick, A., & Morfett, J. (1993). <i>Hydraulics in civil & environmental engineering</i> (2nd ed.). London: E & FN SPON. Chow, V. T., Maidment, D. R., & Mays, L. W. (1988). <i>Applied hydrology.</i> New York: McGraw-Hill. Correia, F. N., Saraiva, M. D. G., Da Silva, F. N., & Ramos, I. (1999). Floodplain management in urban developing areas. Part II. GIS-based flood analysis and urban growth modeling. <i>Water Resources Management, 13</i>, 23-27. Kluwer Academic Publishers. Davies, T. C. (2002). <i>Case studies of water & sewer modeling in a fully integrated GIS environment using MapObjects and ArcView GIS.</i> Available from: <a target="_blank" href='http://gis.esri.com/library/userconf/proc00/professional/papers/PAP359/p359.htm'>http://gis.esri.com/library/userconf/proc00/professional/papers/PAP359/p359.htm</a> Gurnell, A. M., & Montgomery, D. R. (1999). <i>Hydrological application of GIS.</i> Great Britain: John Wiley & Sons. Hassan, A. J. (2004). <i>Analyzing floods on the Kerian River, Malaysia. User case studies.</i> Available from: <a target="_blank" href='http://www.wallingfordsoftware.com/news/fullarticle.asp?ID=243'>http://www.wallingfordsoftware.com/news/fullarticle.asp?ID=243</a> Jurutera Jasa (Sarawak) Consultant for DID. (2003, February). <i>Sungai Sarawak Flood Mitigation Options Study</i> (Vol. I, II, & III) - Main Report. KTA Consultant with CMPS & F Pty Ltd, DHI & UNIMAS for NREB/DID. (Mac 1997). <i>Sungai Sarawak Environmental Control & River Management Study</i> (Vol. 3) - Flood Mitigation Plan. Menozzi, R., Plazz, M., & Schippa, L. (1997). <i>1-D Numerical Model Applied To Flood Routing In Presence of Large Flooded Areas Connected To The River: The Case Study of Senio.</i> Proceedings of 2nd DHI Software User Conference, June 9-11. Star, J., & Estes, J. (1990). <i>Geographic information systems: An introduction.</i> New Jersey: Prentice Hall. Wallingford Software. (2004). InfoWorks RS Models the Juru River, Malaysia. User case studies. Available from: <a target="_blank" href='http://www.wallingfordsoftware.com/news/fullarticle.asp?ID=244'>http://www.wallingfordsoftware.com/news/fullarticle.asp?ID=244</a>