River Ice Modeling for Hydropower Operations at Albeni Falls Dam, Idaho

Abstract

This paper presents a method to quantitatively assess the impact of ice-affected hydraulics on hydropower operations using the widely used HEC-RAS hydraulic model. The model was used to identify historical periods where downstream river ice growth reduced the net head on a US Army Corps of Engineers dam on the Pend Oreille River in Idaho, USA. The model was used to create curves of projected stage impacts based on border ice and continuous bank-to-bank ice-formation scenarios. The temperature modelling capabilities in HEC-RAS were used to hindcast ice formation periods on the river which were validated with shore-based webcam data. These results provide a framework that can be applied to other rivers with hydropower generation, particularly sites where an open water HEC-RAS model exists.