A Review on Flood Events for Kelantan River Watershed in Malaysia for Last Decade ( )

Transcription

1 IOP Conference Series: Earth and Environmental Science PAPER OPEN ACCESS A Review on Flood Events for Kelantan River Watershed in Malaysia for Last Decade ( ) To cite this article: J Aminah Shakirah et al 2016 IOP Conf. Ser.: Earth Environ. Sci View the article online for updates and enhancements. This content was downloaded from IP address on 29/11/2017 at 16:51

2 A Review on Flood Events for Kelantan River Watershed in Malaysia for Last Decade ( ) Aminah Shakirah J 1 L M Sidek 1 B Hidayah 1 Nazirul M.Z 1 M. Jajarmizadeh 1 F.C. Ros 1, ZA Roseli 1 1 Centre for Sustainable Technology and Environment (CSTEN), Universiti Tenaga Nasional, Jalan IKRAM-UNITEN 43000, Kajang Selangor, MALAYSIA Aminahshakirah91@gmail.com Abstract. Malaysia is located at tropical zone and high precipitation area that frequently hit by flood events when it is near monsoon season. This hydro hazard has been one of the main concerns for governmental and non-governmental sectors. High floods lead in financial damages and they are related with human s life. Kelantan watershed is one of the challenging watersheds which mostly suffer from flood events and heavy rainfall events. Flood in Kelantan watershed is related with monetary misfortunes and lives. Clearly, flood have significant influence on various water sectors such water supply, agriculture, human health and eco - systems therefore study of this topic and presentation of available of any data and information can be a valuable baseline for upcoming research in vulnerable case studies. In this study, Kelantan watershed is selected because it is prone to flooding and urban areas classified as vulnerable districts. This overview is discussed on the last decade ( ) floods events in Kelantan. 1. Introduction Malaysia has abandon resources of water resources by receiving sufficient amount of rain yearly. The average annual rainfall for Peninsular Malaysia is 2,400 mm, and for Sarawak and Sabah is 3,800 mm Moreover, flood is related with wet season and two groups of factors fresh waters to flood circumstances such as moderate intensity, long-duration rainfall covering a wide area and high intensity, short-duration localised rainfall. In Malaysia, flood reports shows that seasonal pattern has an important role to produce flood events in east coast and the southern part of Peninsular Malaysia, Sabah and Sarawak which flood occurs mostly during December to January by contribution of northeast monsoon. Increasingly, as we move towards the year 2020, the country is expected to face serious challenges related to flood and drought management. Per capita availability of water will greatly decrease as a result of a growing population and greater per capita use of water for a better quality of life, urbanization and industrialization. Malaysia has been involved with a long time by flood disaster since The country has experienced major flood events in the years of 1926, 1963, 1965, 1967, 1969, 1971, 1973, 1979, 1983, 1988, 1993, 1998, In 1886, Kelantan was faced with a severe flood with gale-force winds. Later in 1926 the worst flood affected most of Peninsular Malaysia. Next, during 1967 huge flood circumstances happened across Kelantan, Terengganu and Perak river basins. In 1971, a catastrophic flood swept across many parts of the country such as Pahang. Recently, in December 2006 and January 2007 flood was main concern of governmental issues for Johor. Finally, flood occurred in Kelantan in 2014 which made a catastrophic phenomenon for who lives in urban area. Nevertheless, the objective of this study is the review of flood event and analysis of flood events in last decade ( ) in Kelantan. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Published under licence by IOP Publishing Ltd 1

3 2. Material and Method 2.1 Case Study Kelantan covers an area of 15,099 km2 in Malaysia and it is located on the north eastern region of Peninsular Malaysia (Figure 1). Kelantan comprises of ten administrative districts, which are Kota Bharu, Tumpat, Machang, Pasir Puteh, Bachok, Jeli, Tanah Merah, Pasir Mas, Kuala Krai and Gua Musang. Flood prone river at Kelantan state are such as Sungai Nenggiri, Sungai Galas, Sungai Pergau, Sungai Kelantan, Sungai Golok, Sungai Kemasin, Sungai Pengkalan Chepa, Sungai Pengkalan Datu and Sungai Semerak. Therefore, Kelantan state deserves to have study for flood review and analysis based on availability of data owing to monsoon season and heavy frequent rainfall with high intensity. Usually, monitoring the trends of the flood in Kelantan and identification of various extreme rainfall and runoff events are recorded by Department of Irrigation and Drainage (DID) Malaysia. Moreover, the water levels are frequently exceeding the danger level. Hence, summarization of raw data and primary analysis help for decision making on later studies 2.2. Primary Knowledge and Analysis Figure1: Map of Sungai Kelantan catchment and main rivers Figure 2 illustrates the prone flooded area from year in Kelantan. It is clear that downstream of especially in Sungai Kelantan Catchment, north of Kelantan state is badly affected more than the upstream area. Therefore, urban areas in northern part of watershed are more vulnerable by flooding. The Kelantan River has large tributaries, namely the Lebir, Galas, Pergau and Nenggiri rivers. The two principal tributaries, the Lebir and Galas rivers merge immediately upstream of Kuala Krai after which the Kelantan river meanders over a wide and flat coastal plain before discharging into the South China Sea. Figure2 shows eastern part of Kelantan has more contribution with flood in comparison with west, it might be related with Lebir and Galas rivers which joint before downstream of Kelantan. Moreover, Northeast monsoon starts from early of November and ends in the end of March. The climate of the study area is generally hot and wet throughout the year with little variation. In addition, it is also characterized by uniform high temperature, high relative humidity and heavy rainfall. The catchment is influenced strongly by the Northeast monsoon which brings along heavy rainfall in the months of November to December. The long duration of the rain events cause prolonged flooding along some stretches of the river. Based on the DID flood report, during the Northeast Monsoon season in 2009, Kelantan has been involved with two phase flood on the 5th - 11th November 2009 (first phase) and 20th - 26th November 2009 (second phase). The flooded area include territorial at Kota Bharu, Tumpat, Pasir Mas, Pasir Puteh, Bachok, Tanah Merah, Machang, Kuala Krai and Jeli. 2

4 3. Results and Discussion 3.1. Extreme Hydrological Events at Kelantan Figure 2: Flooded area at Kelantan in last decade In Nov 2009, Kelantan has suffered from several waves of flood due to influence Northeast monsoon. The 1st wave of flood started from 5 Nov until 10 Nov Highest 24-Hr rainfall of 358.0mm was recorded at Kusial on 6 Nov Maximum annual stream flow for Sungai Kelantan in 2009 was recorded on 23 Nov with amount of 8014 m 3 /s. At that time, Sungai Kelantan was loaded with large amount of rainfall water introduced by 2nd wave of flood (20-28 Nov 2009). Figure 3 and Figure 4 shown below are the rainfall hyetograph for Sungai Kelantan at Kusial from 5 10 Nov 2009 during the 1st wave and from Nov 2009 during the 2nd wave of the flood event. Figure 3: Rainfall Hyetograph for Sg. Sungai Kelantan at Kusial from 5 10 Nov 2009 (1st wave) Figure 4: Rainfall Hyetograph for Sg. Sungai Kelantan at Kusial from Nov 2009 (2nd wave) Figure 5 and 6 shows the stage hydrograph for Sungai Kelantan at Kusial during 1st and 2nd wave of flood in Nov It is observed that the maximum water level recorded during 1st wave was 18.06m on 7/11/2009 (01:00) which exceeded danger level (16.0 m) of about 2.06 m. The maximum water level recorded during 2nd wave was 18.66m on 23/11/2009 (08:00) which exceeded danger level (16.0 m) of about 2.66 m. 3

5 Figure 5 Stage Hydrograph for Sungai Kelantan at Kusial from 5 10 November 2009 (1st wave) 4. Conclusions Figure 6 Stage Hydrograph for Sungai Kelantan at Kusial from November 2009 (2nd wave) Extreme storm events are attributed to several contributory factors. Among the contributory factors, intensity/duration of precipitation is widely adopted in relating to hydrological extreme events. Assigning arbitrary thresholds of precipitation or flow amplitude is deemed as the onset of an extreme hydrological event. The thresholds could be chosen either on the basis of hydrological parameters related to recurrence interval or in relationship to such levels that crossing them leads to significant economic losses. As conclusion, the extreme rainfall event is showing increasing trend as well as the pattern of flood event is showing the increasing trend. The analysis of the hydrological flood event will be used as an input into the flood forecasting model. Hence, it is crucial to compile and analyze major hydrological extreme events which could serve as a reference in the planning and management of water resources projects especially for introducing additional safety factors in the design of water resources projects. Acknowledgement This research is a Long-term Research Grant Scheme supported by Ministry of Higher Education Malaysia (MOHE) collaboration with Japan International Cooperation Agency (JICA) under project Research and Development for Reduction Geo-Hazard Damage in Malaysia Caused by Landslide and Flood. This project also owes to the government sectors Department of Irrigation and Drainage (DID) Malaysia and International Centre for Water Hazard and Risk Management (ICHARM) Japan. References [1] Chan N W 1995 Final Report A Contextual Analysis of Flood Hazard Management in Peninsular Malaysia 7-8 [2] Chia C W 2004 Buletin Ingenieur Managing Flood Problems in Malaysia ISSN [3] Department of Irrigation and Drainage (DID) 2009 LAPORAN Banjir Unit Hidrologi Jabatan Pengairan dan Saliran Negeri Kelantan [4] A.M. Jafri, Z. Hashim, M.L.Kawas, Z.Q Chen, N.Ohara Development of Atmospheric Based Flood Forecasting and Warning System for Selected River Basins in Malaysia [5] A.M Jafri 2011 National Conference on the Impacts of Climate Change on Water Resources and their Consequences to Major Economic Sectors Implementation of Climate Change Adaptation Programmes for Water Resources Development Projects [6] Ong S H 2011 National Symposium on Climate Change Adaptation Goals and Aspirations for Coastal and Water Resources in the Context of Climate Change Adaptation 4