[Thailand] Bangkok to Levy Wastewater Treatment Fees in 2027: "Polluter Pays" Takes Effect, 4–8 Baht per Cubic Meter for Enterprises

Introduction

The Bangkok Metropolitan Administration (BMA) and the Metropolitan Waterworks Authority (MWA) signed a memorandum of understanding on wastewater management, announcing that wastewater treatment fees will officially be levied on large enterprises and factories from early 2027: industrial enterprises using less than 2,000 m³ of water per month will be charged 4 baht/m³, while large factories using more than 2,000 m³ will be charged 8 baht/m³. First-year collections are expected to reach about 200 million baht, easing the reliance of the roughly 800 million baht annual wastewater treatment cost on general municipal tax revenue. Bangkok Governor Chadchart Sittipunt made clear that the core of the fee is the "Polluters Pay Principle," making polluters pay for environmental governance and avoiding passing costs on to ordinary citizens.

Background: From "Municipal Welfare" to "User Pays"

For a long time, Bangkok's wastewater treatment operations have depended heavily on fiscal subsidies. The city's eight wastewater treatment plants currently cost about 800 million baht a year to operate, entirely covered by general tax revenue. This fiscal pressure has grown year by year and created the structural contradiction of "polluters bearing no cost while operators cannot make ends meet." The new BMA–MWA cooperation mechanism is precisely aimed at shifting wastewater treatment from "municipal welfare" to a sustainable "user pays" operating model, laying the financial foundation for subsequent network expansion and new plant construction.

In institutional design, the fee adopts fine-grained management with "two tiers, exemptions and boundaries in parallel": the first tier targets industrial enterprises using less than 2,000 m³ of water per month (Type 2 wastewater sources), charged 4 baht/m³; the second tier targets large factories using more than 2,000 m³ per month (Type 3 wastewater sources), charged 8 baht/m³. At the same time, enterprises and hotels that build their own wastewater treatment systems and meet effluent standards can apply for exemption, while operators outside the service areas of the eight treatment plants are not covered by this fee. The relevant fee legislation is being drafted and will systematically cover fee subjects, rate adjustment, collection management and dispute handling.

Core: The Rate Mechanism and Policy Signals

This fee releases three policy signals. First, the establishment of a cost-recovery mechanism — Bangkok formally recognizes that wastewater treatment is an environmental public service with costs that must be shared by beneficiaries and polluters, with fee revenue earmarked for plant and network O&M and expansion. Second, the emergence of a leverage effect — at a rate of 4–8 baht/m³, large factories using more than 2,000 m³ of water per month could see their annual water costs rise by 192,000 baht or more, significantly boosting the economic incentive for "source reduction and recycling." Third, the institutionalization of compliance-based exemption — the "self-built compliant systems are exempt" design is essentially using economic means to reward enterprises that proactively treat their own wastewater, guiding large water users to build efficient treatment facilities and forming a dual drive of "market incentives + administrative regulation."

For the water and environmental protection industry, this is a landmark event in wastewater fee reform at the megacity level in Southeast Asia. As a regional economic center, Bangkok's fee model is highly likely to be emulated by tourism and industrial cities such as Pattaya, Chiang Mai and Phuket, creating a chain reaction across Thailand and even ASEAN.

Significance: What This Means for Us

Bangkok's wastewater fee reform has direct business relevance for TIANYI TECH. On the one hand, the "self-built compliant systems are exempt" clause means that large Chinese-funded factories, industrial parks and hotel complexes in and around Bangkok will generate concentrated demand for self-treatment wastewater facilities — precisely the target scenario for our complete wastewater treatment and water reuse equipment. On the other hand, the 8 baht/m³ fee will significantly raise the comprehensive cost of water for enterprises, greatly shortening the payback period of "water reuse and cascading utilization" solutions and making equipment-based solutions more cost-competitive.

We can map out an entry strategy for the Thai market accordingly: first, target large factories and industrial parks within the service areas of Bangkok's eight wastewater plants with two product lines — "pretreatment + compliant discharge" and "advanced reuse"; second, follow the regulatory details accompanying BMA/MWA fee legislation and build compliance-exemption certification requirements into solution design upfront; third, cooperate with Chinese-funded EPC partners in Thailand, using "rising wastewater fees" as a marketing lever to promote water reuse retrofits to existing clients and seize the window created by Thailand's water cost reform.

Industry Perspective: Our Judgment

At the industry level, Bangkok's wastewater fee is an important milestone in the marketization of Southeast Asia's water sector. Unlike Vietnam, which is driven by central environmental budget investment, Thailand is following a path of "user pays + PPP to attract private capital," placing more emphasis on operational efficiency and cost recovery. We believe the Thai market's business model will evolve from "selling equipment" to "equipment + operations + fee sharing," with integrators that possess O&M capability capturing higher added value. As we advance our Thai business, we will build professional capability in PPP and O&M cooperation models in advance, converting the market expansion brought by wastewater fee reform into a long-term, sustainable overseas revenue growth point.