Potential storage augmentation impacts on hydropower production, irrigation water supply and environmental flows in the Indus Basin in Pakistan

Abstract

Study region: Indus River basin, Pakistan Study focus: The study assesses the implications on irrigation water reliability, hydropower production and environmental flows to the Indus Delta resulting from the implementation of large new storages on the Indus River. These large dams have the potential to impact water supply security of the Indus Basin Irrigation System which operates with a priority of maximising irrigation supply via the 1991 Water Apportionment Accord. Implementation of the Accord under future scenarios involving new large dams is open to interpretation. This study uses the daily time step Indus River System Model to simulate the potential impact of these new large dams on hydropower production, irrigation water supply and flows to the Indus Delta under different Accord interpretations. New insights for the region: Pakistan possesses significant potential for increasing hydropower production from the Indus River through the construction of new reservoirs, which could raise the nationwide share of electricity generated from hydropower from 29% to 44–53%. This study demonstrates that augmenting storage capacity can yield threefold benefits – improved end-of-system environmental flows, more reliable irrigation supply for the Rabi season, and increased hydropower production. Additionally, this modelling approach can be instrumental in strengthening the existing water governance arrangements when considering the construction of new dams, thereby improving the health of the Indus delta ecosystem through the construction of dam construction.

Keywords

• River basin management
• Hydropower
• Irrigation
• Environmental flows
• Modelling
• Indus delta