With the reference to the Pahang Flood in 2014, you are required to write a summary on this flood. Your summary should include (1)rainfall event, (2)runoff, (3) infiltration, (4) damages, (5) flood level and (5) suggest any appropriate approach to reduce the flood impact in the future. Please support your answer with an appropriate reference.(2 pages)
Flood is severely happened in Malaysia region. Basically there are two major flood type occur in Malaysia which is flash flood and also flood due to monsoon. The flood that occur at Pahang last year can be identified as monsoon flood.
Pahang is the third largest state in Malaysia, after Sarawak and Sabah, and the largest in Peninsular Malaysia. The state occupies the huge Pahang River river basin. It is bordered to the north by Kelantan, to the west by Perak, Selangor, Negeri Sembilan, to the south by Johor and to the east by Terengganu and the South China Sea. Pahang severely having flood event every year since it is influence from the north east monsoon and last year is the worst flood event occur. It cause 40000 affected people to be evacuated to the relief center. The intensity of the rainfall that cause flood is 920 mm for three days compared with 355mm over a full month. It is the maximum value for rainfall intensity with heavy rain. The velocity of the air is 50 km/h and it brings the heavy rainfall to Kuantan city and paralyzed the city activity. Until 4 Disember 2013, the flood water level had increase into 1 meter on the road. The monthly precipitation for Pahang area is 684.6mm and mean monthly precipitation is 208.4mm. The maximum monthly flow of the river in Pahang is 1697.4 m³/s and it is expected that in the near future the flow will increase to 718.1 m³/s due to urbanization and land use change. The maximum monthly air temperature for Pahang area is 28.3 °c and the mean monthly air temperature is 26.1 °c. Pahang flood event had crippled eight district. The damage of this flood is cost RM390 million. The mitigation should be made to reduce the impact of the flood.The system that been use currently had been overwhelming by heavy downpours coupled with high tide. Month before the flood seasons, state goverment agencies had conducted flood mitigation work such as widening drains, building bunds at Sungai Isap and deepening Sungai Galing. Unfortunately flood is still happened and it is worse than last year event. The most effected area is Kuantan with more than 27000 people evacuated. Several mitigation action can be proposed in order to reduce the flood impact. Generally flood mitigation can be divided into two which is structural method and un-structural method. Structural method is included the building of floodwall along Pahang River. These will cater the river overflow into the city. Another mitigation plan that can be done is by canal deepening. It is believe that Pahang river is not sufficient to receive huge amount of discharge from the land. Due to siltration from upstream. Because of that river dredging must be done. River dredging should be made gradually instead of only during the flood seasons. With the deepening of the river, the river can cater more water discharge from the upstream.
Under the un-structural method, there are several things that government should look onto. First is on the warning systems. Our flood warning system is still weak compared with other country. Warning systems is important since to make sure that people who living in the flood prone area can prepare what to do and what not. This can reduce the impact of flood event. Second is on the study of flood prone area. Recently there are still lack of study about future flood event in Pahang. Using the outdated data will cause the future prediction vary from what is really happened. A study on flood forecasting should be made seriously by local authority and all the data should be assessable by citizen. Third way is by proper use of land planning. Pahang severe flood is believe caused by the poor city plan by the state government and local authority. Construction of building is approved even in the flood plain area and close to river. What will happened was the construction will interrupt the soil system at that area and the soil will be transported through river flow into the downstream. The soil will deposited in the river and siltration happened. That will cause flood to occurred. Flood is also cause by the canal clog in the city. This is due to lack of ethics of local citizen to through rubbish into the river systems. Action could be made is by educated the people on the river pollution. The wrong doing and the cause should be explain to them in order to reduce the flood occurring factor. Law and enforcement need to be upgrade suitable with current situation.
References
1 Jamaludin, 2010, Trends in Peninsular Malaysia Rainfall Data During the Southwest Monsoon and Northeast Monsoon Seasons : 1975-2004.
2 Salmah Zakaria, Impact of Climate Change on water : Focus Malaysia.
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