Currently, dams are generally proposed and built one at a time, with little or no understanding of how continued development will ultimately affect river systems and other values. A system-scale approach, which the Conservancy calls Hydropower by Design, seeks to compare alternative development scenarios upfront and identify those scenarios that can most effectively balance energy development with the protection of other social and environmental resources. Additionally, risk to funders could be reduced because the approach identifies potential issues that should be addressed early on, leading to fewer conflicts down the road.
We evaluated Myanmar’s Myitnge River, a tributary of the Ayeyawardy, and the values it provides for communities, its potential for generating power, and the outcomes that could result from hydropower development. Our results clearly showed that energy development produces tradeoffs with other resources and values. However, there are many different options to increase energy generation and these options very widely in terms of their impacts. A system-scale approach can identify “win-win” or “close to win-close to win” options—these are options that meet energy objectives but minimize negative impacts or have synergistic benefits for other sectors (e.g., navigation). These balanced options are highly unlikely to emerge from a set of project-level decisions. For example, as generally expected, a larger number of dams in the Myitnge sub-basin was projected to increase fragmentation, flow alteration, and sediment and nutrient trapping, thus reducing the sub-basin’s contribution to the overall fish productivity in the Ayeyawardy basin. However, there are several combinations of dams and operating rules that would produce almost the same amount of energy, but with potentially much lower impacts on fish productivity.
Hydropower can be part of a sustainable energy future if designed and operated in a manner that avoids or minimizes impacts on people and vital river functions. As hydropower development increases around the world, many will be looking to Myanmar to see if it can sustainably develop hydropower while maintaining the diverse other values its rivers provide.