The management of downstream flows from hydropower projects is an essential element of sustainable hydropower development, but there can be disagreement amongst stakeholders over the objectives, magnitude and timing of flows required.
Hydropower projects can significantly alter downstream river flows by changing flow dynamics to follow energy demand, by reducing flow to a bypassed stretch, or by increasing flows due to diversions.
These alterations can lead advocates to call for increased or changed flow regimes for purposes other than hydropower generation, often to maintain and support a river’s ecological and morphological processes and its ability to deliver ecosystem services to people.
Compromises are necessary to satisfy downstream social and ecological objectives in partnership with a profitable and reliable hydropower project. Each case is individual and requires dedicated investigation of flow requirements.
Downstream flows objectives will differ greatly depending on the river, its communities and interactions, and the influence of hydropower on flows. A pragmatic approach is paramount, and collaborative approaches amongst major stakeholders are encouraged to better understand the river's ecological values and how best to protect and enhance these.
Latest associated content
We are taking the pulse of the hydropower sector at large in this year's annual issues survey. You are invited to take part.Type:Blog postDate:24 November 2016
There is growing recognition that site selection is critical for successful hydropower development.Type:Programme itemDate:13 October 2016
The IHA Blue Planet Prize will be awarded in 2017, and is open for participation. The award recognises hydropower projects that demonstrate excellence in sustainable development.Type:Blog postDate:11 March 2016
33 GW of new hydropower capacity was commissioned in 2015, including 2.5 GW of pumped storage, according to estimates in our new briefing, 2016 Key Trends in HydroType:Blog postDate:1 March 2016
In December 2015, the International Hydropower Association (IHA) carried out an annual issues survey for the first time. This new, annual initiative aims to take the pulse of the hydropower sector at large, monitor key issues faType:Blog postDate:1 March 2016