Subdaily Hydropower Optimization for Relicensing in the Connecticut River

Abstract

There is significant evidence that altering river flows downstream of reservoirs harms native aquatic ecosystems and decreases the ability of native species to strive and survive. Innovative water management is needed to improve the health of native aquatic species and their surrounding ecosystems while maintaining the benefits from historic operating policies at these facilities. The Connecticut River is the largest river basin in New England and one of the most impounded rivers in the United States. Five hydropower facilities along the Connecticut River are undergoing Federal Energy Regulatory Commission (FERC) relicensing. These facilities respond to both seasonal and hourly power demands. This relicensing process provides an opportunity to explore and alter the operations of these facilities utilizing coordinated reservoir management practices that investigate different operating objectives. This study presents an optimization model that investigates the value of coordinated reservoir management practices for ecological benefits at the major reservoirs undergoing relicensing. Optimization models have a long history of application in reservoir operation studies. One important use of optimization models on large-scale water management projects is to trade off different operational objectives of hydropower facilities. This research explores the use of optimization models in reservoir operations to address objectives related to emerging environmental concerns in the hydrologic regime while addressing historical operating objectives for management of hydropower reservoirs in the Connecticut River. Results suggest that coordinated operational changes to current hydropower reservoirs can restore some aspects of the natural hydrologic regime necessary for ecosystem persistence without considerable losses to current economic benefits.