Case Study: Northfield Fish Passage Study

Northfield Mountain Pumped Storage Project Fish Passage Study (2-D Model)

FirstLight Power Resources (Northfield, MA)


As part of the FERC relicensing process for the Northfield Mountain Pumped Storage Project, Gomez and Sullivan is conducting a study to evaluate the effect of project operations on fish passage in the Connecticut River. Work involved public presentation of the study plan, field collection of bathymetric and water column velocity data, development and calibration of a two-dimensional (2-D) hydraulic model, and preparation of a report. The 2-D model was developed using River2D for a 10-kilometer portion of the Project’s lower pool, which is also the impoundment for FirstLight’s Turners Falls Hydroelectric Project further downstream on the Connecticut River. A total of 60 different scenarios were run, which altered the baseflow in the river, Northfield operations, and Turners Falls operations. The results of the model were used to evaluate the potential impact of Project operations on upstream migration of adult shad and downstream migration of juvenile shad due to flow reversals, velocity barriers, undesirable attraction flows, and entrainment/impingement on the trashrack structure.