Thailand has 22 major river basins and 27 groundwater sources . For decades, Thailand has been facing problems related to its water resources, including water shortage, drought, floods, decreased groundwater levels and saltwater intrusion in its groundwater sources , . For instance, severe droughts occurred in 1979, 1994, and 1999, which affected every part of the country, and over the last 10 years, an increasing number of recurring droughts have affected a total area of 42,280 km² . These droughts have caused significant disruptions to the Thai economy because of severe water shortages that affect agriculture, consumption, and ecological systems. The persistent drought event during 2015 – 2016 (considered to be the worst drought in 20 years in the country), resulted in considerable losses exceeding US$ 2.5 billion, affecting agriculture (especially rice paddies) heavily. Similarly, the drought of 2019 was estimated to cause losses of US$ 312 million due to lost crops from rice, maize and sugar cane to tapioca . Thailand is also highly exposed to floods, which are by far the greatest natural hazard facing the country in terms of economic and human impacts , .
Despite water shortage problems , in general, Thai people have been able to sufficiently access drinking water; the proportion of household members with access to clean drinking water has increased from 97% in 2012 to 98% in 2016 and 99.5% in 2019. However, the quality of water available remains a challenge for the country. Data from the Ministry of Public Health’s Report on Drinking Water Quality from 2009-2019 showed that only 40.8% of water available to households was appropriate for consumption. On the other hand, 43.7% of water in households needed further treatment before consumption, while a further 15.5% comprised water that had been contaminated by chemicals above the recommended limit. Additional studies have also shown that about 59.2% of water used in households is not at the required standard. Much of these water resources came from sources provided by local government bodies .
In terms of access to hygiene, data from 2019 shows that 89% of household members in Thailand had access to a designated hand-washing facility and that 97.1% had access to toilets without having to share. However, poorer and less-educated households continue to face challenges in accessing hand-washing facilities and toilets .
Several water-related challenges coexist in Thailand. Growing population, economic growth, rapid urbanization and the looming threats posed by climate change are expected to make sustainable water management significantly more difficult in the coming years .
Continued economic and social growth, coupled with the transition towards industrial agriculture, has increased Thailand’s competitive water demands . In 2021, total water demand in the country reached about 100 billion m³; of which, agriculture accounted for 82.5% of total water demand. This was followed by demand for ecosystem conservation, consumption, and industry at 12.81%, 3.73%, and 0.98%, respectively .
Population growth and an increasing number of tourists in the country, along with inadequate drainage systems, has resulted in pollution of surface water sources and thus the deterioration of water quality. In 2018, the percentage of water from surface water sources at the required water quality stood at 91%. By 2019, this had deteriorated to 82%. Additionally, the percentage of water sources of poor quality doubled from 9% in 2018 to 18% in 2019 . Concerning groundwater quality, some areas in the country have high iron and manganese, resulting from geological and hydrogeological conditions. As was found in 2020, some sites of shallow groundwater layers in Thailand are also contaminated with heavy metals and volatile organic compounds from landfills and waste disposal sites of industries and some industrial estates .
As the climate continues to change, Thailand is increasingly experiencing impacts from water-related threats. Incidences of drought in the dry season and flooding during the monsoon season are becoming more common, with nationwide impacts that disproportionately affect low-income communities who rely heavily on natural resources and agriculture for their livelihoods .
Key policies and governance approach
Aiming to manage the country’s water resources effectively and align with SDG 6 (ensure availability and sustainable management of water and sanitation for all), Thailand has formulated the 20-Year Master Plan on Water Resources Management (2018-2037) . This plan is divided into six dimensions, namely: (1) water resources management for domestic use; (2) creating water security for the production sector; (3) flood and water-related disaster management; (4) water quality and conservation; (5) upstream forest restoration and soil erosion prevention; and (6) management approach . Additionally, the country has passed the Water Resources Act (2018), which is the main piece of legislation encompassing work in this area . The Act covers the entire water resources system and assigns the ministries that oversee the country’s water resources . Further, Thailand has also established the Office of National Water Resources (ONWR) as the focal point for all relevant agencies  and the central authority that oversees implementation of the Master Plan .
Thailand is also prioritising the provision of equal and standardised access to toilets and sanitation. During the COVID-19 crisis, the Department of Health raised awareness on the importance of correct hand-washing procedures and evaluated the readiness of business owners in providing hand-washing equipment such as soap, alcohol gel, and disinfectant for customers. Additionally, in the long-term, the Department of Health is developing the Draft Masterplan on Toilet and Waste Management (2018-2029), which is comprised of 5 key strategies: (i) increasing the use of sanitary and safe toilets; (ii) increasing the quality of public toilets in line with the lifestyles of the Thai people; (iii) the comprehensive development and management of toilets and waste; (iv) development of the national sanitation system; and (v) the creation of comprehensive sanitation knowledge and habits .
Successes and remaining challenges
Thailand has made great progress in the management of its water resources. Overall achievements include: (i) the proportion of household members able to access clean drinking water has improved from 98% in 2016 to 99.5% in 2019; (ii) in 2019, the Royal Irrigation Department increased water storage capacity by 16.7 million m² and increased the amount of irrigated land; (iii) the Department of Water Resources and the Department of Groundwater Resources set a target to reduce the amount of water lost from 25 to 20%; (iv) in 2019, the Ministry of Interior, as the responsible agency for developing the water consumption system, expanded water systems in all provinces and the Bangkok Metropolis to over 26,000 additional households; and (v) from 2018-2019, Thailand implemented measures to revive 177.5 km² of up water forest areas, which represents 15% of the target set in the Water Management Masterplan .
Despite great progress, the country still faces challenges in implementation of Integrated Water Resources Management (IWRM), for which its main implementation mechanisms are the Master Plan on Water Resources Management and the Water Resources Act. Although the Water Resources Act already exists, IWRM cannot be fully implemented because there are many laws that are redundant in its implementation. Budgeting for structures such as reservoirs, water control structures, floodgates, etc. is also a problem and a barrier to the management of water resources in Thailand. In addition, the institutional framework dedicated to water resources management is still fragmented, which limits the effectiveness of IWRM. While the Act assigns the ONWR the role of central agency for coordinating all relevant agencies, time is required to ensure effective coordination and integration under the Act. Further, in order to support effective implementation, the government should push for improved understanding of IWRM in the public sector, local government organisations, and water user groups in all sectors .
Initiatives and Development Plans
Thailand has been implementing the Thai-German Climate Programme (TGCP), which encompasses comprehensive water management cooperation between Thailand and Germany . The TGCP-Water aimed to enhance the national framework conditions for climate-sensitive IWRM and Ecosystem-based Adaptation (EbA) solutions to prevent and reduce the impacts of climate change and water-related disasters at national and river-basin levels .
Under the TGCP-Water, Thailand’s Office of National Water Resources, together with IUCN and GIZ launched ‘The Guidebook for the Design and Implementation of Ecosystem-Based Adaptation in River Basins in Thailand’. This guidebook aims to serve as a framework for developing, implementing, and mainstreaming Ecosystem-based Adaptation (EbA) measures in river basins throughout Thailand. The Guidebook is also complemented by the Climate Risk and Vulnerability Assessment Tool developed by the Hydro Informatics Institute, which provides a step-wise approach for conducting climate risk vulnerability assessments, as well as the EbA Code of Practice (COP) developed by the Thailand Environment Institute to help inform the design of EbA measures. The project team also conducted a series of consultations and trainings with government officials and River Basin Committees to ensure that the tools are suitable for their work .
Thailand is also a member of a number of international frameworks on water resources management, such as the Mekong River Commission (MRC), Mekong-Lancang Cooperation (MLC), and the Lower Mekong Initiative (LMI) .
- A system for connecting the operations of all authorities at all levels should be created .
- A central data centre which connects information from the various authorities needs to be developed to provide quick access to accurate information. This system should include information on the general condition of basins, water management, plans and projects, maps, water users and water sources, etc .
- This database could also be used by authorities to monitor and report on implementation .
- Furthermore, the database could then be used to facilitate the decisions of the government, the NWRC, basins committees and provinces on water resources management .
- There is a need to improve understanding of the Water Resources Act and IWRM amongst people, stakeholders, authorities, and local government organisations .
- Local government authorities and development partners have a central role to play in connecting policy at the national level to the local level and in addressing data gaps with regards to water management. Thus, the capacities of local government authorities need to be developed and local participation increased .
- The process of public participation needs to be strengthened to provide a network for surveillance and monitoring of implementation. Channels should be created for public information dissemination so that people can access information in a timely manner .
- A policy for public-private partnership should be promoted to allow the private sector to invest with the public sector in the development of water resources, based on good governance and transparency in further operations .
- Because of climate change, the ONWR must prioritise access to water resources from public sources for domestic use .
- There is a need to upscale Ecosystem-based Adaptation (EbA) efforts to address increasing climate threats in the country .
- The government should also improve the enabling environment to promote good standards and habits on sanitation .
 OECD (2022). Managing and Financing Water for Growth in Thailand: Highlights of a National Dialogue on Water, OECD Studies on Water, OECD Publishing, Paris, https://doi.org/10.1787/839a4f70-en.
 Department of International Organizations, Ministry of Foreign Affairs of Thailand (2021). Thailand’s Voluntary National Review on the Implementation of the 2030 Agenda for Sustainable Development 2021.
 Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH, Office of the National Water Resources (ONWR), International Union for Conservation of Nature (IUCN) (2022). Guidebook for the Design and Implementation of Ecosystem-based Adaptation Measures in River Basins in Thailand.
 Office of National Water Resources (ONWR) (2020). The Thailand Report: Country Survey Instrument for SDG Indicator 6.5.1. [Online]. Available: http://iwrmdataportal.unepdhi.org/country-reports.
 GIZ Office Bangkok (2022). Thai-German Climate Programme – Water. [Online]. Available: https://www.thai-german-cooperation.info/en_US/thai-german-climate-programme-water/.
 IUCN, International Union for Conservation of Nature and Natural Resources (2023). New guidebook promotes Ecosystem-based Adaptation within Thailand’s Water Sector. [Online]. Available: https://www.iucn.org/story/202302/new-guidebook-promotes-ecosystem-based-adaptation-within-thailands-water-sector.