Confronting Polluted Floodwater Problems in Bangkok
Bangkok, Thailand, featuring the Chao Phraya River. Image by Wilfried Strang from Pixabay
Thailand is a Southeast Asian country with a population of close to 70 million people spanning almost 200 thousand square miles. Being located within the tropics, Thailand has three distinct weather seasons - hot season, rainy season, and dry season. The hot season lasts from March to around mid-May, the rainy season from mid-May to October, and the dry season from November to February. Bangkok, the capital city, experiences slightly different weather patterns than the more inland areas of the country. It is hot all year round, and comparatively more humid than other areas due to experiencing the urban heat island effect. While flooding is a major issue in Bangkok and something that will be further discussed in detail, it is also important to note that Bangkok often suffers through droughts. This is caused by the Chao Phraya, the river that leads into the city, reaching an extremely low level that then causes seawater to move into the river to the point where residents can taste salt in their drinking water. Currently, the city is experiencing its worst drought in 4 decades. Half of all the major reservoirs are below 50% capacity and the monsoon season is shortening, which in turn, is causing below-average rainfall.
Population and Transportation
Bangkok is one of the world’s most populated cities, with a population of almost 11 million people. The map below shows the population density in people per square kilometer in each district. Although they are the smallest, the districts closest to the Chao Phraya River are the most densely populated. Blue dots are markets and black dots are instances of government housing.
Population Density of Bangkok
Bangkok also has one of the highest vehicle densities on the roads. There are roughly 9.7 million registered vehicles, comprised of both cars and motorbikes.
There are several means of public transit infrastructure, including a skytrain, metro, airport rail link, express boats, and buses. Many of the vehicles, cars, and motorbikes alike, serve as a taxi service for tourists and individuals who do not own a means of transportation.
Flooding
Bangkok during the 2011 floods. Image by Philip Roeland from Flickr
A Look at Bangkok’s Flooding History
1970: Tropical Storm Ruth damages railroads and harms the agriculture sector
1975: 6.0 Richter scale earthquake
1980: Flooding causes damage in 9 provinces causing Thailand to take action and start thinking about long term flood prevention
1983: Tropical Depressions Herbert and Kim cause destruction in 42 provinces and destroy over 200,000 homes
1986: Heavy rains rendered roads and footpaths unusable
1994: Flash flood kills over 16 people
1995: Floodwaters reach 2.27 meters and last for several weeks causing over 400 people to die
2011-2012: Flooding causes damage in 65 provinces affecting over 13 million people and damaging roughly 21,000 square kilometers of farmland
Canal Systems
Khlong Saen Saep Express Boat, Bangkok Thailand. The Khlong Saen Saep canal is one of the major canalways in Bangkok. Image by David McKlevy from Flickr.
Bangkok’s canal system started being built in the 1780s. Before extensive roads were developed, boating through the canals was the primary method of transportation.
Bangkok has 1,682 canals, the total length of which comes out to 2,604 meters in length. Many exist as a means of flood drainage, but some are primarily hosts to water transportation and water markets.
Flooding and Flood Water Management
Flood levels in Bangkok can reach up to two meters in depth, and often have a devastating impact on transportation infrastructure in the city. The map below shows bodies of water in Bangkok and the deepest the waters can be expected during a flood, as well as the floodgates shown with orange points and areas most susceptible to flooding shown with white points.
Credit: Flooding Isolated by L Wood
Waste Management Problems
Bangkok and the Chao Phraya River. Image by deepgoswami from Flickr.
Sieng Kong Zone (car parts market in Soi Wanit 2) in Samphanthawong District, Bangkok, Thailand. Image by Globe-trotter from Wikimedia Commons.
The Chao Phraya River is considered the most polluted river in the world. The water pollution comes not only from the people of Bangkok, but also from the ocean, in terms of saltwater infiltrating the water supply.
The government infrastructure for waste collection is insufficient, and much of the waste collection is handled privately. Because of the lack of formal landfills, open-air, roadside, and empty-lot dumps have started emerging over time. These dumps aren’t managed, making it a health hazard that impacts water and air quality.
The public is uninformed about the impact of waste on their surroundings. Plastic consumption among consumers is high, despite the government’s efforts to push a “reduce, reuse, recycle” mindset.
Waste Levels
The map on the left displays the quantity of tons of solid waste for each district and the map on the right displays waste density in term of tons of solid waste per square kilometer for each district. The numbers utilized in both maps come from waste data for the year 2018. Brown points indicate locations of waste centers and blue points indicate water quality treatment centers
Waste Quantity
Waste Density
The Compound Problem
It is clear that Bangkok is facing a flood issue that due to climate change, is only getting worse. It is also important to note that the majority of the flooding happens in areas with higher population density. This means that there are large groups of people, businesses, and infrastructure being affected by every incident that takes place. Coupled with the amount of unregulated waste on the streets of Bangkok, a flood could easily cause an extreme public health crisis, especially due to the fact that the canals connect the waterways. In addition, pollution in the Chao Praya flows downstream into the Gulf of Thailand. From here we can look at the issues from three interconnected lenses:
Climate Change
Waste Management
Increased and Rapid Urbanization
It is the combination of the above three factors that have created the problem Bangkok is facing today. The rapid pace of urbanization did not allow for proper urban planning and the creation of the necessary infrastructure, which in turn led to the poor waste management being seen today, and climate change only aids in exasperating these issues. Finding a long-term and sustainable solution will require asking questions and seeking answers that carefully consider all three above factors. Questions such as:
How can this human-produced waste be kept out of the water?
How can urban drainage systems be improved and/or created to better deal with the amount of waste being produced?
How can urban growth and development be tracked and projected in order to better prepare for the future?
How can urbanization be controlled to prevent stress from being put on the infrastructure?
Looking Abroad: Bali, Indonesia
Littered beach, Bali, Indonesia. Image by GRID-Ardenal from Flickr.
Bali is dealing with a similar problem with waste levels beginning to pollute the water supply. As a response, the government in Bali has started to ban certain plastic products, although the regulations are often ignored by the people.
Looking forward, Bangkok may need to also consider policies restricting plastic use, but could go a step forward by reducing the sale, production, and importing of plastic products. This could prevent such large pileups of waste in the streets that end up in the water supply whenever there is flooding.
Zooming In
This is a cartogram diagram showing the relative size of the districts based upon the amount of waste they produce.
Waste Quantity Stack Diagram
The above diagram is showing waste quantities from the ten districts that produce the most waste over the course of 9 years, from 2010 to 2018. Other than an overall dip in 2011 and 2012, the years of major flooding in Bangkok, there is trend towards higher waste production with every coming year. The dip in the data may indicate that there was less solid waste collected by the city during years with flooding due to that solid waste being picked up in the flood waters and subsequently deposited into the Chao Phraya River. It becomes clear that waste quantity can not be solved as a stand-alone problem, but must be looked at in tandem with flooding and water damage.
Bangkok Waste Sankey Diagram
This diagram is starting to get more specific about the waste being produced in each district. It is showing how each of the districts is zoned, the amount in tons of waste being produced, and what specific type of waste it is. Knowing what kind of waste is being produced then allows for an understanding of how to dispose of it. As seen in the diagram, food waste is the main waste being produced, with non-recyclable plastic coming in second. These two types of waste require methods of disposal and therefore a more complex design proposal.
Proposal
The amount of waste being produced, and the type of waste, is too much to be processed through the currently existing Municipal Solid Waste management service. This means that less organic waste needs to be produced or the waste service needs to increase capacity. Realistically, waste production will not significantly decrease due to the population size, and building new infrastructure will take time and money.
Community Education. Solid Waste Management in Bangkok | Department of Environment
As seen from the data above, the majority of waste is coming from residential areas. We predict that if trends continue the way they are with no intervention, the amount of waste produced will multiply with time. This led to the conclusion that focus should be placed on waste regulations for residential areas and management of food waste. Implementing composting programs on the city level in conjunction with community education around food waste could aid in reducing the amount of food waste not only being produced but having to be processed through the municipal management service. It would also be recommended to have the government implement city-wide plastic recycling pickup throughout residential neighborhoods. Once again, through community education, residents would be able to learn the importance of recycling but more importantly, it would reduce the load being placed on the Municipal Solid Waste management program.
The proposals above are all short-term solutions to temporarily remedy the problem. There is no way to get around the fact that more infrastructure and waste centers need to be built in order to handle the amount of waste being produced in Bangkok.