Dynamic operating rules for water supply reservoirs in La Paz

Abstract

Dynamic operating rules have been applied to the drought-prone Andean water supply reservoirs near La Paz, Bolivia. The water supply reservoirs are not using conventional reservoir operating rule curves. Instead, dynamic operating rules opportunistically supply surplus water for soft demands, and proactively adjust the water supply before a drought causes a water shortage. The conventional approach of forcing water levels to follow a set rule curve is replaced with notions of tradeoffs between long-term reliability and short-term supply opportunities. Operators can customise the dynamic rules based on their tolerance of shortages, and can choose to operate more aggressively during wet periods. In this way, the dynamic rules offer a flexible tool for making short-term decisions while managing medium and long-term performance goals. In the case of La Paz, it is possible to utilise the water sources more efficiently in the short-term without significantly reducing the long-term water supply reliability. The dynamic rules will reduce the severity of future water shortages (if they occur) by 60%, and provide opportunities to increase the firm water supply by up to 8% without affecting the long-term reliability.