The estimated hydropower potential of the lower Mekong Basin (i.e., excluding China) is 30,000 MW, while that of the upper Mekong Basin is 28,930 MW. In the lower Mekong, more than 3,235 MW has been realized via facilities built largely over the past ten years, while projects under construction will represent an additional 3,209 MW. An additional 134 projects are planned for the lower Mekong, which will maximize the river's hydropower generating capacity. The single most significant impact—both now and in the future—on the use of water and its management in the Mekong Region is hydropower.

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