The report also summarizes new lines of research conducted over the course of the last year by the MDM team, namely a discussion of drivers of the expansion of the Tonle Sap Lake in Cambodia and a historical analysis of how dams in the Sekong, Sesan, and Srepok (3S) rivers (three long Mekong tributaries) are changing flows in the 3S Basin and the Mekong mainstream at large. [...] Since it is now understood that large storage dams in the Mekong Basin refill their reservoirs during the wet season and release water from reservoirs during the dry season for hydropower production, the effect of these operations is a reduction of extremes by bringing the wet season floods down and raising the river level during the dry season. [...] Across the two periods, the number of alerts related to significant restrictions of flow which drop the level of the river downstream were similar to previous years, but the number of alerts for sudden releases in this timeframe were less than half that of the previous year. [...] As the wet season rains subside, the level of the Mekong mainstream drops again and water begins to flow back out of the Tonle Sap Lake, returning the Tonle Sap River to its normal direction of flow toward the ocean. [...] While the sustainability of Cambodia’s fish catch and the annual expansion and contraction of the Tonle Sap Lake has been a question of concern for decades, Mekong watchers grew particularly concerned about the state of the Tonle Sap during the string of low wet season flow years which ran from 2019-2021.
- Pages
- 88
- Published in
- United States of America
