In the past, a healthy Mae Ping River ran through Chiang Mai in the northwestern part of Thailand. It flowed south, merging with three other rivers -Wang, Yom and Nan- to become the Chao Phraya River, Thailand’s major river and source of water for millions of people. The Ping River was part and parcel of the daily lives of Chiang Mai residents. “Water provided us with fish, crab and shells”, remembers an old Chiang Mai resident. “Once the water was clear but now it has become a smelly and polluted wastewater carrier”, says Mr. Surachet Nokham, Chiang Mai’s Wastewater Treatment Plant Manager.

A polluted river not only stirs residents’ nostalgic memories of past recreational activities in and along its waters; a filthy Ping River poses both human and environmental health issues, and may also threaten the image of Chiang Mai as the “Northern Rose” of Thailand.

One of the main drivers of pollution is the discharge of untreated domestic wastewater directly into the river. This results in a deterioration of water quality, which impacts on human and environmental health as well as releasing significant greenhouse gas (GHG) emissions, a major contributor to climate change. Worldwide, about 80 % of all wastewater is discharged into the environment without any treatment, with many regions lacking the basic infrastructure to better manage wastewater. Treating the wastewater we release back to nature would address issues of water quality, environmental health and GHG emissions.

Thailand’s Wastewater Management Authority (WMA) was founded in 1980 to take responsibility for national wastewater management, and provide management and technical assistance to municipalities operating wastewater treatment systems. Mr. Chira Wongburana, Acting Director General of WMA, has recognized this as a priority, “The first and foremost water management issue that we need to address is to bring back clean water”.

Through the International Climate Initiative, the WMA is now working with the Water and Wastewater Companies for Climate Mitigation (WaCCliM) project to optimise wastewater management at pilot utilities in Chiang Mai, Hat Yai, Krabi and Sansuk. In Chang Mai, studies identified untreated wastewater flowing  into the public canals of the city as not only polluting its waterway so that they were no longer fit for bathing, but also that it was producing significant amounts of methane and nitrous oxide, both GHGs with a large global warming potential.

The utility plans to install gauging stations at five wastewater discharge points where the water flows into the Mae Kha canal to control the public canal of Chiang Mai City. Mr. Surachet expects “to see a better quality of water in several water courses”.

Wastewater treatment is not only a key piece of the solution to Thailand’s acute water pollution. In a country prone to the effects of climate change, where wastewater treatment accounts for about half of the total GHG emissions of the waste sector and contributes to high energy related emissions, wastewater treatment becomes an area with huge potential for mitigation measures. Participation from citizens, governments and the private sector are crucial to set this in motion.

“If we are able to take the steps at the sources of wastewater, less energy will be required in the treatment process, reducing greenhouse gas emissions. Having an efficient wastewater treatment system in the industrial sector, as well as participation from citizens in saving water and not throwing rubbish into water sources, will help reduce GHG from the wastewater sector”, stated WMA Director General, Mr. Chira. “If both the public sector and citizens participate, I believe Thailand can reach the reduction target of 20-25% by 2030 that it committed to at the climate change conference in 2015. We already have a roadmap for 2021-2030 and the wastewater sector will reduce its emissions by 3.6%”, he concluded.

Based on this roadmap, wastewater treatment can contribute up to 30% of the total GHG mitigation potential in the Thai waste sector. The water and wastewater sector can become a catalyst for climate action in other sectors within Thailand; if they succeed, Thais might once again swim and fish in the country’s waterways.

Watch this short documentary:

WaCCliM in Thailand from WaCCliM on Vimeo.