3. Deforestation
Without these forests, there will be no vegetations to intercept the rainwater. Besides that, since Thailand is geographically sloped at an angle, without trees to secure the soil together, it will increase the chances of soil erosion. As such, soil and mud will be washed into rivers, causing it to be shallower. Also, the bare slopes that remained will result in increased surface runoff. All these factors contribute to the flooding in Thailand.
1. Damage to industrial estates and global supply shortages
On 8 October 2011, the flood had caused the collapse of a 10 metre high water blockage in Nikom Rojna industrial estate which housed many manufacturing plants. The strong currents interfered with reconstruction efforts and resulted in the whole area being non-operational.
Thailand is responsible for approximately 25% of the world's production of hard disk drives. However, numerous factories, including Western Digital's, that are in charge of the production of hard disk drives were flooded, leading to some industry analysts to predict future worldwide shortages of hard disk drives. Nonetheless, the problem was alleviated when Western Digital managed to re-operate one of their plants.
2. Sanitation concerns
As the flood water subsides, it will leave behind stagnant pools of water which may cause the effects of trash and sewage within them to peak. In addition, since a household sanitation system is unable to operate under flood water, individuals that remained in flooded areas exposed themselves to risks and also increased the risks for those living downstream by continuing to produce more sewage and trash in waters carried downstream.
As a result of these stagnant water and water pollution, it will encourage the growth of bacteria and mosquitoes which will result in the spread of dengue fever, malaria, cholera and other diseases which are detrimental to our health.
3. Loss of lives and Economic Damages
As of 6 November 2011, the flooding has affected 3,151,224 people from 1,154,576 families, with 506 deaths and 2 missing persons. The total damages summed up to approximately 185 billion Baht. 930 factories in 28 provinces were flooded, causing many industrial processes to halt. It was estimated that the flood will result in a decrease of 0.6 to 0.9 percent in economic growth.
Solutions
1. Building of dykes
Dykes were already being built in Bangkok to prevent floods. Dykes are made up of sand, stone and concrete and are built along river banks which are prone to flooding. These dykes increase the capacity of the river to hold water and hence reducing the chances of flooding. So, through the building of more dykes, the Thailand government hopes to reduce the effects of flood significantly.
2. Building of dams
Building of dams is another way in which the Thailand government implemented to reduce floods. The main purpose of a dam is to control the amount of water that flows downstream in a river. Gates are being installed in the walls of dams to hold back or release water from the man-made reservoir behind it. This reservoir also serves a purpose in preventing flood simply by increasing the amount of water that a river system can hold upstream. Currently, dams had already been constructed on the Ping river (the Bhumibol Dam) and on the Nan River ( the Sirikit Dam)
3. Building of new underground canal
The Engineering Institute of Thailand came up with a proposal to build a underground tunnel that stretches 100km with a diameter of 24 meter and a depth of 10km in order to reduce the impact of floods. The construction will take at least 2 years and it will cost about 200 billion baht. This underground tunnel will be connected to existing canals and will act as an expressway to allow water to flow directly and quickly into the sea without any impact to the communities. With this new tunnel, it will boost the drainage capacity of the city to 130 million cubic metres a day.
4.Watershed management
New ways to deal with floods include managing the entire water shed. The Royal Forest Department(RFD) in Thailand is an example where it has developed a watershed management programme to prevent floods from occurring. This programme comprises detailed plans on conserving the natural vegetation in watersheds. By conserving vegetation cover, surface runoff and the amount of sediments washed into rivers are reduced. This in turn reduces the occurrence of floods. The RFD programme also includes re-planting trees in areas where they were previously cut down. The planting of trees and grass on slopes reduces surface runoff and soil erosion, thereby decreasing the chances of flooding.
Evaluation of the 4 solutions
Out of the 4 solutions, we feel that building of the new underground canal is the most effective solution.
The building of dykes can only prevent floods for a short period of time. As time goes by, the dykes will be eroded by the water which may cause it to collapse and thus, the government will have to carry out checks on a timely basis to ensure that it is still in working conditions. This will require a huge planning process and would not be cost effective as it needs to make use of large amount of manpower to carry out the checks.
Managing a watershed environment for the prevention of floods is a perfect example of "Prevention rather than Cure". It emphasizes on how we can make preparations before the flood comes instead of trying to salvage the remains and aftermath later. However, we feel that even if this project is successful, it would be extremely costly to continue funding this project and to sustain it. The vegetation might not be suitable to grow in that area and often, external factors such as heavy thunderstorms and droughts might cause the plans to wither away or to collapse and fall. Plants are also weak, vulnerable and susceptible by nature. Thus, they can only rely on circumstantial factors to survive. In conclusion, this is not a good suggestion.
As for the construction of dams, without an efficient draining system, floods will still occur. Dams only allow about 2 billion cubic metres of water to flow into the Gulf of Thailand via the three rivers. During the rainy season in Thailand, there will be about 100billion cubic metres of water to be accumulated. This will definitely mean that it will take 50 days for the water to be completely drained away.Therefore, it is not time-efficient enough to be considered the best strategy.
However, with the help of new underground canal, the number of days for the water to be drained away will definitely be reduced significantly. Therefore, with the construction of new underground canals, it will help to reduce the impact of floods.
