this sector has in what concerns hydropower a longterm plan up to and prepares a mediumterm plan every ten years which is frequently updated it is regulated by the aneel the successor of the dnaee which operated the largest hydrometric network that was transferred to the ana after its creation if this creates a significant constraint for river basin planning it also creates many opportunities because water reservoirs can be used for multiple uses in fact dams change the flow regime downstream but create a more stable and reliable source of water for all uses especially in areas affected by large variability of precipitation as happens in semiarid regions characterised by water scarcity