Bangkok is advancing a model to transform the On Nut landfill site into a 580-rai forest, having planted nearly 50,000 trees, with the goal of becoming a Green Eco Park model.
On 11 July 2026, Chatchat Sitthiphan, Governor of Bangkok, conducted a Facebook Live broadcast from the On Nut waste disposal center on On Nut Soi 86. He inspected environmental restoration efforts, measures to resolve odors disturbing nearby communities, and plans to upgrade the site into a large green space for Bangkok.
Governor Chatchat revealed that the On Nut waste disposal center has operated for over 30 years and covers a large area of 580 rai. Originally, it was just a large landfill, but over the past four years, Bangkok has improved the landscape and restored the soil layer by planting more than 48,000 trees. Additionally, trees transplanted from city construction projects were nurtured and planted here under the concept “trees are the city’s treasure.” Today, the former landfill has transformed into a lush forest, attracting birds and wildlife, reflecting a clearly recovering ecosystem. Bangkok is planning to create trail running paths for public exercise in the future.
Deputy Governor Pornprom Na S. Wikitset explained progress on tackling odor problems, admitting most odors come from the old composting plants with capacities of 600 and 1,000 tons. Bangkok’s permanent solution is to wait for contract expirations: the 600-ton plant’s contract ends late 2026, and the 1,000-ton plant’s contract ends in June 2027. Afterwards, these factory areas will be fully converted into green space.
“We acknowledge that we cannot eliminate the odor completely at this time. While awaiting contract expiration, Bangkok has strictly supervised contractors, ordering upgrades to closed waste transfer stations, installing dedicated wastewater treatment plants, and installing CCTV to monitor daily waste disposal to prevent accumulation. If contractors neglect duties, Bangkok will impose fines and demand immediate corrections. In the future, the system will switch to a 1,000-ton waste incinerator producing clean energy, and composting plants will be replaced by gas-to-electricity plants operated by Krungthep Thanakom,” Governor Chatchat added.
Moreover, Bangkok has introduced electronic nose (e-Nose) technology around the area to measure and monitor odors in real time, which vary with wind direction each season. The e-Nose reports odor levels in Dilution to Threshold (D/T) units. Monitoring shows peak odor levels around 5 D/T, never exceeding the set control standard of 9 D/T. For transparency, Governor Chatchat pledged that within next week, Bangkok will publish the e-Nose odor data online so residents and media can monitor odor conditions 24 hours a day.
For the long term, Bangkok aims to develop the On Nut waste disposal center into a Green Eco Park (GEP), a sustainable urban waste management model. The plan allocates the area evenly: half as green forest to filter air and serve as the community’s lung, and half as a modern, closed, environmentally friendly waste management system to minimize impact on residents in On Nut, Phatthanakan, and Chalerm Phrakiat areas. It also aims to become an international environmental study center. The public is invited to support the project by planting two million trees to help reduce Bangkok’s heat together.