Sustainable Water Management Using Environmental Flows In The Connecticut River

Abstract

There is significant evidence demonstrating that altering river flows downstream of impoundments harms native aquatic ecosystems and decreases the ability of native species to strive and survive. Innovative water management practices are 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 impacts of individual reservoir operations on ecosystem health are often masked by the compounding influence of multiple upstream impoundments, making it difficult to analyze an individual facility's impact within the larger system. This study presents an optimization model that investigates the value of coordinated reservoir management practices for ecological benefits in a dynamic system with several major reservoirs operating for hydropower production. An application of this model is presented for five hydropower facilities along the Connecticut River using The Connecticut River Environmental Assessment Model (CREAM). The Connecticut River Basin 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) re-licensing. These facilities respond to both seasonal and hourly power demands. CREAM includes the five facilities undergoing this re-licensing process. This process provides an opportunity to explore and alter the operations of these facilities utilizing coordinated reservoir management practices that investigate a variety of operating objectives. This study provides an opportunity to contribute to the long history of using optimization models to explore tradeoff between different operational objectives of hydropower facilities. This research explores the various 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.