Figure 2.2 The Lower Mekong Basin boundaries shared by four countries (Cambodia, Myanmar, Lao PDR, Thailand, and Vietnam).
Source: Google LLC.
The headwaters of the Mekong River, originating in the Tibetan Plateau, is vital for maintaining flows accounting 18% (China, 17%; Myanmar 1%) of annual flow and 40% of the dry season flow in the mainstream river. Tributaries flowing in Lao PDR are the largest contributor of the annual flow accounting over 40%, while remaining three countries contribute below 20% each.
Lao PDR, Thailand and Vietnam have jointly established the Mekong River Commission (MRC) – an inter‐governmental organization – in 1995 by the signing of the Mekong Agreement (MRC, 2016a). The MRC aims to jointly manage the shared water resources and the sustainable development of the Mekong River. China and Myanmar, the upstream countries, are dialogue partners of the MRC. Since its establishment, MRC has emerged as a regional hub on information sharing, providing advice, and a platform for policy dialogue and engagement with private sector and civil society to address sustainability issues in areas such as fisheries, agriculture, navigation, hydropower, disasters, ecosystems, and climate change (floods, droughts, sea level rise). Along with the rapid pace of development in the region, pressures on the LMB water resources have also surged substantially such as upstream‐downstream tensions caused by planned and ongoing construction of a cascade of hydropower dams, competition for water withdrawal for irrigation and drinking water supply, fishing, disaster (droughts and floods), climate change (including sea level rise in the delta areas), and loss of natural water‐related ecosystem (Table 2.1).
Table 2.1 Country specific issues related to water resource management in the LMB.
| Issues | Impacts/ Results | |||
|---|---|---|---|---|
| Cambodia | Lao PDR | Thailand | Vietnam | |
| Hydropower dam development in China, Lao PDR and Cambodia | ‐Changes in river flow regime and TSL water level ‐Reduced sediment deposition and nutrient flow ‐Fish migration and water ecosystem | ‐Revenue from the hydropower (internal use and export) and potential flood control ‐Water for irrigation | ‐Import of electricity ‐Water supply | ‐Change in river flow regime ‐Dam operation to control flood and release water to maintain minimum flows (potential) ‐Storm surge due to reduced flow in dry season |
| Water withdrawal | ‐Low flows in the river due to water abstraction by Thailand and Lao PDR | ‐Irrigation and drought mitigation | ‐Irrigation and drought mitigation | ‐Low flow in river due to water abstraction in the upstream |
| Climate Change, El Nino, disasters | ‐Changes in monsoon rainfall and river runoff (too high or below average flow condition in wet season) ‐Inundation floods and limited flash floods ‐Inadequate inundation and sedimentation in TSL and rice fields ‐Prolonged drought | ‐Changes in monsoon rainfall and river runoff ‐Flash floods and some inundation types ‐Impact on irrigation and hydropower generation ‐Prolonged drought | ‐Changes in monsoon rainfall and river runoff ‐Flash floods ‐Impact on irrigation and hydropower generation (imports) ‐Prolonged drought | ‐Changes in monsoon rainfall and river runoff ‐Inundation floods ‐Prolonged drought ‐Sea level rise and storm surge during dry season |
| Economic development and land use changes | ‐Soil erosion and runoff of agro‐chemicals ‐Pollution due to discharge of wastewater, pollutants and toxic leaks during water navigation | ‐Soil erosion and runoff of agro‐chemicals ‐Pollution due to discharge of wastewater, from mining and toxic leaks during water navigation | ‐Soil erosion and runoff of agro‐chemicals ‐Pollution due to discharge of wastewater, pollutants and toxic leaks during water navigation | ‐Soil erosion and runoff of agro‐chemicals ‐Pollution due to discharge of wastewater, pollutants and toxic leaks during water navigation |
SDGs offer a fresh perspective to priorities and could address water resource management issues in a systematic manner in the LMB. Since each country has been impacted disproportionately by changes in the LMB, SDGs could be a useful framework for these countries to manage trade‐offs choices while reinforcing a spirit of cooperation that was built over the past 20 years through the Mekong Agreement and MRC. To be sustainable, SDGs should not be pursued in a way that achieving goals in one riparian country would incur high trade‐offs in other countries.
Table 2.2 summarizes the most recent state of SDG 6 implementation in the LMB countries. Drinking water and sanitation are two major targets for which all countries have achieved a remarkable progress in terms of improving access, financing, and monitoring. In the LMB countries, over 75% of the population now have access to improved drinking water, and over 70% in case of access to improved sanitation (except in Cambodia where it is slightly over 42%). Apart from WASH related targets, state of other targets (including on hygiene) have not been frequently updated mainly due to lack of recent data or state of the progress is limited. For instance, water stress was not really high for most of the country (<14%) but the reference data is over a decade old. Although the LMB countries have fairly higher per capacity water availability (3303 m3/person to 27992 m3/person in 2014) when compared to just over 1100 m3/person in India, per capita water availability has been subsided by 2–19% between 2002 and 2014 (ADB, 2017). On the other hand, water productivity (used as a proxy of water use efficiency in this paper) is quite low (<7 US$/m3) when compared to global average of over 18 US$/m3 in 2014. Less than 5% of generated wastewater are treated in case of Vietnam, Lao PDR, and Cambodia while in Thailand the treatment ratio is around 20% (WEPA, 2015). There has been a rapid loss of original natural wetlands although data are limited to verify the most current state (MRC, 2016a). In case of pollution control, there are standards for ambient water quality but state of water quality are not readily accessible except for some sites monitored on monthly basis by MRC and published annually. In case of IWRM implementation, it is well integrated in both national policies as well as in MRC basin management plans. Transboundary cooperation exists through MRC as well as bilaterally, such as hydropower generation between Lao PDR and Thailand. Community participation is often promoted as a part of specific projects or programs.
An assessment by Asian Development Bank (ADB) finds that score of National Water Security Index (0–100) of all four countries ranges between 37.5 and 54, which means these countries are engaged in improving water security and shown modest improvement when compared to hazardous state of water security (i.e. score below 36) (ADB, 2016). This leaves a wide challenge space for these countries to improve water resources management while implementing SDG6.
Observations in Table 2.2 on the status of SDG 6 reveals that all four countries seriously lack adequate data required for monitoring the progress. Except for WASH, most of the shown data are not from recent dates and thus do not reflect current situation. The situation is also reflected in the VNR submitted by four LMB countries