Through Bangkok, The City of Angels: The Polluted Chao Phraya

In bustling Thailand’s capital city of Bangkok, 948 canals flow into the Chao Phraya River, and from there to the sea. Since 2015, over 387,000 tonnes of trash have been removed from the city’s canals, and those that are not, got washed away into the Gulf of Thailand.

Chao Phraya River begins at Nakhon Sawan province and flows 372 km south through Bangkok and exits in the Gulf of Thailand. In Bangkok, it is a major transportation network of river buses, cross-river ferries, and water taxis (“longtails”), with more than 15 boat lines operating on the rivers and canals of the city.

Circular Economy Bangkok Chao Phraya Mumbai India Environmental NGO Earth5R

Chao Phraya River from above (

Culture wise, the Chao Phraya is of high significance as a survey done by the Department of City Planning team found more than 200 sites which are to be preserved as national heritage sites along the river.  

As Bangkok is located in the Chao Phraya Sub-basin, it made this part of Chao Phraya the most important sub-basin economically, contributing 78.2% of the total GDP of the Basin.


The mainstream of the Chao Phraya River was home to about 190 native fish species. Due to extensive habitat destruction caused by pollution, dams, and irrigation drainage, it has been estimated that only 30 native fish species are able to reproduce. 

Circular Economy Chao Phraya Bangkok Mumbai India Environmental NGO Earth5R

Giant freshwater stingray (Wikipedia)

The catfish, Platytropius siamensis, is endemic to Chao Phraya and has not been recorded since the 1970s and is considered extinct. Giant barb, giant pangasius and giant freshwater stingray which are three of the largest freshwater fish in the world that are native to Chao Phraya are also seriously threatened and endangered.


The Lower Chao Phraya, where Bangkok is situated, is one of the top 5 water sources

with poor water quality in Thailand, according to PCD (Pollution Control Department).

In 2018, the lower Chao Phraya was ranked first by PCD as the province with the poorest water quality index only scoring 35% out of 100%. 

Chao Phraya Bangkok Circular Economy Pollution Mumbai India Environmental NGO Earth5R

Wastewater discharge in Chao Phraya (Bangkokpost)


There are 30,000 industrial facilities along the Chao-Phraya River, which run through Thailand’s major cities – including the capital, Bangkok – a city of around 14 million people. This factor contributes to the poor quality of the water. 

Many factories in Bangkok are small scale and larger plants are located near the port. Factories in Bangkok consists mainly of textiles, food processing, electronic equipment assembly, and the production of building materials.

Roughly one-third of the country’s output from industrial parks is produced in Bangkok. 

In a 2016 PCD report, the average level of dissolved oxygen in the lower Chao Phraya was 1.9 mg/L when the required standard for a good water body is 5 mg/L. The NH3-N (Ammoniacal nitrogen)  level was also noted to be 0.1-1.5 mg/L when the permissible limit is 0.5 mg/L. 

The abundance of NH3-N leads to the growth of water hyacinth in several points in Chao Phraya River which is bad for aquatic life as it covers the water surface not allowing oxygen to penetrate hence, the low level of dissolved oxygen.

Chao Phraya Bangkok Circular Economy Algal bloom Mumbai India Environmental NGO Earth5R

Water hyacinth along Chao Phraya River (PBS)


Limited affordable housing in the urban areas has made those with low incomes to have informal settlements along the canals. As time goes by, canals become more densely populated, which contributes to household wastewater discharge – further deteriorating water quality.

For instance, in 2001, domestic wastewater made up 81% of water pollution in terms of BOD (Biological Oxygen Demand) load coming from the Bangkok Metropolitan Area Chao Phraya sub-basin. And a report in 2007 stated that only 13% of domestic waste is treated.

Chao Phraya Bangkok Circular Economy waste segregation Mumbai India Environmental NGO Earth5R

Houses along Chao Phraya River in Bangkok, Thailand (Luther Bailey Travel Blog)

In a PCD report from 2016, the Total Coliform Bacteria (TCB) was averaged to be 24,000 MPN/100 mL and 7,900 MPN/100 mL for Faecal Coliform Bacteria (FCB). TCB are the bacteria from human and manure waste while FCB is the level of contamination that is likely to harbor bacteria that can cause digestive disease.

According to the U.S EPA, water above the thresholds of 2,300 mpn/100ml TCB and 400 mpn/100ml FCB were associated with gastrointestinal illnesses. 

The lack of wastewater treatment plants is one of the contributing factors too, as only 21 out of 50 districts have their wastewater treated properly.


Not only wastewater discharges, but plastic waste has also always been a problem in Thailand. An average Thai uses approximately 8 plastic bags a day which adds up to 500 million plastic bags per day for the whole nation.

In 2019, an average of 2,115 tonnes of plastic was thrown away in Bangkok per day. Not all of these plastics are disposed of properly, some got washed into the river or are even deliberately thrown in. 

Chao Phraya Bangkok Circular Economy Composting Mumbai India Environmental NGO Earth5R

Floating trash in Chao Phraya River, Bangkok (Scandasia)

One of the clean up done in 2017, gave a picture of how severe the problem is. In total, 132 kg solid waste comprising of 2000+ plastic bags, 700+ plastic bottles, 600+ plastic cups/cartons, 900+ glass bottles, 1300+ styrofoam, 150+ clothing-related, 1500+ small plastic piece was collected just in the span of one hour over only 6 km of the river stretch. 

These wastes – if not taken out – are going to eventually end up in the ocean as Chao Phraya flows to the Gulf of Thailand. 80% of the plastic waste in the oceans originates from land and eventually polluting beaches and harming marine animals. 


Loy Krathong is a festival of lights where people gather near water bodies to pay respect to the water goddess. They float (Loy) Lotus shaped craft (Krathong) decorated with flowers and lit up candles and incense on top of it into the water.

Chao Phraya Circular Economy Bangkok Mumbai India Environmental NGO Earth5R

Floating of Krathong, Loy Krathong Festival in Bangkok (Go Thai Be Free)

In 2017, city officials of Bangkok fished out 811,945 Krathong from the waterways of which 51,964 Krathong were made from non-biodegradable styrofoam. 

This is a big problem as styrofoam is slow to degrade, and if disposed of improperly, the foam can leach chemicals into the environment harming water sources.

Chao Phraya Bangkok Circular Economy Waste Mumbai India Environmental NGO Earth5R

Municipal city workers picking up krathongs in 2019 on the Chao Phraya in Bangkok (Aswin Kwanmuang / Facebook)



  • The Thai Cabinet has approved a roadmap to tackle plastic waste during the years 2018-2030 and to reduce or end the use of certain types of plastic because of its increasing harm to the environment.
  • The three types of plastics are microbeads, cap seals, and oxo-degradable plastics.
  • At the beginning of 2020, Thailand Administration put a ban on single-use plastic bags at major stores.
  • In the case of wastewater treatment from factories and household discharges, the cabinet has given the go-ahead for a 20-year master plan for water management, aimed at solving Thailand’s chronic drought, flood, and wastewater problems.
  • The plan targets supplying clean water to 75,032 villages by 2030, solving floods and droughts in 66 areas covering 55.36 million hectares, building more than 541,000 small dams, and restoring 5.6 million hectares of watershed areas.


  • Thammasat University operates with several organizations to campaign “Kayaking for Chao Phraya” for 10 days in 10 provinces, including Bangkok from 1 – 10 October 2019. The campaign is to encourage people to stop throwing trash in the river and raise awareness on plastic usage. 3,215 kg of trash was collected from the river with more than 100 kg being hazardous waste such as pesticides, paints, and solvent.
Community Chao Phraya Bangkok Circular Economy Mumbai India Environmental NGO Earth5R

Kayaking For Chao Phraya clean up (QS wow news)

  • On Earth Day 2019, The Plastic Bag Monster Project called attention to the overuse of plastic bags in Bangkok. Bangkokians use approximately eight plastic bags per day. This ‘plastic bag monster’ went around stores in Bangkok while wearing the 600 plastic bags on the suit which represents three months’ usage for the typical citizen.
Bangkok Community Plastic Circular Economy Mumbai India Environmental NGO Earth5R

The plastic bag monster in front of a 7-11 store (

  • The ‘Preserving and Improving the Chao Phraya River through Sustainable Water Management’ project was done by IconSiam, Chaipattana Foundation, and communities living along the banks of Chao Phraya river to engage and raise awareness of local people living along the river about the need to revive and conserve natural resources and the environment, leading to sustainable living.
Chao Phraya Bangkok Community Circular Economy Mumbai India Environmental NGO Earth5R

Taking the trash out from the Banks of Chao Phraya River (The Nation)


It’s obvious that plastic pollution is still a problem in the Chao Phraya river as clean-ups done always found lots of plastics and other wastes. 

The problem of pollution in lower Chao Phraya won’t be solved unless there is a community awareness on the problem especially for the informal settlements along the river which don’t have proper sewage management. 
Even with the ban of plastic bags in major stores, the abundance of street vendors (approximately, more than 500,000 street vendors) in Bangkok City alone, still use plastic and most of the time even double bags the parcel.

Bangkok Plastic Recycle Circular Economy Mumbai India Environmental NGO Earth5R

Streetfood vendor in the process of double-bagging (Nicolas Axelrod/Bloomberg)

Citizens are not encouraged to segregate waste and even when they do, there is no proper place for the disposal of the segregated waste. 

According to one study, 64% of the Thai population do not sort their rubbish

In addition, 40% of the trash that is generated could be recycled, but only 18% of it is actually recycled.


The quality of the water reflects what we do on the land as well as what we do in the water.

A circular economy is an economic system aimed at eliminating waste while reducing the continual use of resources. It combines economic, environmental, and social aspects to solve existing problems. It is breaking with the model of the linear economy, by proposing to transform waste into recycled raw material for product design or other uses.

Community along the banks of the river and also all over Bangkok can apply the model by:

  • A community waste bank and recycling center to intercept the waste before it goes to the landfill. The waste collected can then be recycled into something useful thereby creating a source of livelihood for someone. Awareness-raising activities on different types of plastics and how to segregate them will also help.
Circular Economy Upcycle Recycle Mumbai India Environmental NGO Earth5R

Bottle caps collected by the Earth5R team to be upcycled into new useful products, such as benches (Earth5R)

  • Behavioural change is vital. Initiatives that combine both science and educational programmes to provide awareness of the problems so people can know what’s the consequences of their actions.
  • Have an awareness program for people – especially for the informal settlements communities along the canals – on basic knowledge about proper waste segregation and disposal and upcycling plastic that can lead to entrepreneurship and generate incomes. 
Bangkok Circular Economy Women Empowerement Mumbai India Environmental NGO Earth5R

Environmental Awareness and Social Entrepreneurship Program at Pune, India (Earth5R)

  • Incorporating citizen science for riverside schools where students can learn about dissolved oxygen level and other water quality parameters. Other citizens can also report pollution in the river. 

Reach out to Earth5R to know more about solving environmental issues by creating a circular economy based sustainability projects.


Earth5R is an environmental organization from India with its head office at Mumbai. It works with the NGO sector, Companies and helps them conduct environmental corporate social responsibility (CSR) programs across India. Earth5R specializes in circular economy based projects. Earth5R also offers short term and long term environmental courses. 

Earth5R’s Global Sustainability Hub is a cross-sector and cross-country collaboration in pursuit of UN Sustainable Development Goals. It is an excellent opportunity for governments and the private sector to engage with communities, use Sustainability-based models to drive economic changes and create social and environmental impact.

Reported by Shafa Azzahra, edited by Riya Dani

Recognised as


Earth5R Email address

to top