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Going beyond watershed boundaries: lessons from Nong Han Lake

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Going beyond watershed boundaries: lessons from Nong Han Lake

The last 20 years have seen the widespread use of Integrated Water Resources Management (IWRM) to manage water resources in Southeast Asia. A recent field visit to the Nong Han Lake in northeast Thailand showed the importance of “going beyond the watershed” for improved water management.

Uttam Ghimire / Published on 22 March 2021 / Nong Han Lake, Thailand

The Nong Han Lake located in Sakhon Nakhon province of northeast Thailand stretches over 120 square kilometers with an average depth of two meters. It is the largest freshwater lake in the northeast, which is primarily used for industrial and domestic supply, irrigation and fisheries. Apart from the direct use of the lake, water leaves Nong Han Lake in other forms: for example, on average, each household around Nong Han annually uses 711 kilograms of nontimber forest products in the form of watermediated resources and the lake system contributes 32% of their average annual income.  

Nong Han Lake in Sakhon Nakhon province of Thailand. Photo by: Uttam Ghimire/SEI

The rice produced in the Nong Han locality is consumed locally and sent to nearby provinces and international markets. In 2019, Sakhon Nakhon province produced 1.3 million tons of rice, a good proportion of which left the watershed boundary as virtual water. While the exact contribution of Nong Han to rice production remains unclear, it is reported that almost 54% of the Nong Han locality produces rice, with rice farming practiced by people from 12 sub-districts of Sakhon Nakhon.

A rice farmer in Sakhon Nakhon province. Photo by: เกษตรพอเพียงบนเทือกเขาภูพาน

The local people depend on the lake fisheries for their protein. The fish in Nong Han are migratory, coming from far downstream in the Mekong River for breeding, spawning and feeding. Any obstruction to the seasonal fish migrations therefore reduces the availability of fish in the lake and its wetlands ecosystem 

The government officials from the Royal Irrigation Department, who are responsible for operating the gates that release water to irrigation canals, informed us that, since the construction of dams along the Mekong River, they have witnessed a decline of almost 50% in migratory fish species. This decline in fish species was corroborated by the local fishers. At least 53 species of fish are found in the Nong Han Lake and wetlands. The large number of fish also attracts many birds, with the lake supporting about 156 different species.  

Local fishing gear installed by farmers in Nong Han lake. Photo by: Uttam Ghimire/SEI

But it is not fishing and agriculture alone that drives the local economy. Around 22.5% of the local people works as migrant labour in the bigger urban areas of Sakhon Nakhon, Nakhon Phanom and Bangkok. A majority of the older population are involved in subsistence agriculture and fishing while younger people tend to leave their homes for higher education and jobs. The migrant workers also send their income remittance back to their homes. Thus, water management plans also need to take into account these additional dynamics of labour and human resource flows.  

Large lake systems like the Nong Han are also beneficial for carbon cycling and regulating the local weather by generating frequent rainfall and cooler temperatures, and help cycle the terrestrial, atmospheric, and aquatic carbon. Apart from climate regulation, Nong Han also is a place for recreation and meditation. The lake has more than 30 small islands, one of which hosts an ancient church considered as a sacred place by locals and tourists alike. 

However, the Nong Han Lake ecosystem also faces several threats. Synthetic fertilizers used in the upstream farms eventually drain into the lake contaminating the water and causing algal blooms. While the surface water quality of Nong Han has been quite good compared to other water bodies in the country, the ongoing expansion of Sakhon Nakhon city is increasing both freshwater abstraction and discharge of wastewater into the lake. At several points in the lake, untreated wastewater is being released into the lake further degrading the lake ecosystem. 

Labourers working in a regional market. Photo by: SEI Asia

What are water teleconnections and why do they matter?  

The term teleconnections can refer to the connections of resources, power or stakeholders over a notional boundary.  

In Nong Han Lake, the current practice of water management by the government of Thailand does not recognize the teleconnections of water beyond the lake’s natural boundary, the wetland ecosystem and its ecosystem services. Moreover, water management does not take into account the involvement of a variety of stakeholders who are in various ways connected to the lake and wetland ecosystems.  

In Nong Han lake, the nearby wetlands play a key role as habitats for the migratory fish species, which are consumed both locally in the region and outside. Similarly, the irrigation water in the vicinity of Nong Han is used for rice production which is then exported to different national and international markets. Meanwhile the World Wildlife Fund (WWF) is making ongoing efforts to attain the status of a Ramsar wetland site of international importance for the Nong Han wetlands to help in the conservation and management of the lake and its ecosystems. 

These teleconnections do not figure in the national water resources development and management plans. Mostly, water management in Nong Han is top-down and involves little or no consultation with local communities or the local government either at provincial or district level. For example, the ongoing 7.4 billion Baht Nong Han water project aims to establish 69 interventions in the lake and nearby systems, 36 of which have been approved already for the project’s first phase in 202122. But the project has gone ahead without effective and open discussions with rural communities who will be affected by it. 


An island in Nong Han where local and international tourists explore their spirituality through meditation. Photo by: Uttam Ghimire/SEI

Boundary jurisdictions 

One ongoing challenge in Nong Han Lake is that the boundaries and jurisdiction of the lake and its nearby land masses are not clearly identified. And it is still unclear which judicial agency The Ministry of Interior or the Department of Lands – is responsible for management of the buffer zones of the lake. Similarly, the locals who farm in these lands do not have official title deeds, which can only be obtained from the central government. Because of this management plans have not been properly implemented in such areas.  

Managing the lake: multi-stakeholder participation outside the watershed boundary  

In Thailand the majority of management plans for water resources, including that of Nong Han, are made at the central government level. Local communities are disconnected from these plans and the centralized policymaking process. Moreover, big developmental efforts are continuously prioritized in Nong Han, while locals prefer smaller scale development that can be more conservation-oriented and cost effective 

The civil society organizations in the area are convinced that the large structural interventions planned by the government, such as dams and irrigation infrastructure, will drastically affect local livelihoods and the lake’s ecosystem. In general, farmers on the ground are satisfied with water user groups and believe that the irrigation water is fairly allocated between these groups. But stakeholders at the middle and lower levels are not so satisfied with the government plans and projects. While the district officers are aware of the situation and try to propose plans that incorporate the needs of locals, it is not often taken up by the central government officials. 

A sunset view from one of the Tambon (village) of Nong Han lake system. Photo by: Uttam Ghimire/SEI

Going beyond the watershed boundar 

Water management plans that are conceived and implemented without genuine consultation and involvement of locals often face resistance.  In the Nong Han region, local communities and civil society groups have already voiced opposition to the construction of infrastructure projects. Local communities feel that they have not been effectively included in, or had sufficient ownership over, the water management plans.  

In Nong Han, there is a need for a more holistic water management plan that accounts for the transfer of water and water mediated resources in and out of the watershed boundary. Those responsible for managing the lake need to recognize the inherent ecosystem services provided by the wetlands in any water-related project. Ultimately, successful water management will depend on the participation and sense of ownership of multiple stakeholders, starting from the early stages of water resource planning all the way through to implementation.  

The author thanks Leonie Pearson, Janejira Chuthong and Thanapon Piman for their inputs and guidance in the writing of this article. 

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Uttam Ghimire

Research Associate

SEI Asia

Topics and subtopics
Water : Water resources
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