Environmental Attribution for the National Hydropower Asset Assessment Program

Oak Ridge National Laboratory initiated the National Hydropower Asset Assessment Program (NHAAP) to gather, organize, summarize, and validate stream networks, hydropower facility configuration, historic generation capacities, and water availability for the entire US within the Department of Energy Water Power Program.  In association with hydropower facility information within the NHAAP database, the Environmental Attribution Effort (EAE) was organized as a means to evaluate and prioritize environmental impacts associated with hydropower energy and provide tools to organize effective mitigation strategies at regional scales.  The objective of the EAE was to compile and summarize spatially-relevant ecological, geopolitical, and socio-economic sources of information associated with hydropower energy development at two scales:  the continental US and individual basins.  Information across the continental US was summarized at the 8-digit HUC scale to provide regionalized potential environmental concerns to organize mitigation strategies, scenarios, and Federal Energy Regulatory Commission relicensing procedures.  Ecological geo-spatial layers at the US scale included identifying federally listed species and species of concern, critical habitats, and fish traits potentially affected by hydropower (anadromy, life history characteristics, etc).  Other layers assessed existing infrastructure, population demographics, water usage across various categories, landscape disturbances (including dam density), and conservation land ownership.  Geo-spatial layers more relevant to individual basins (4-digit HUC scale) included compilations of state-wide databases, information on local species of concern and their habitats, susceptibility of ecological systems to disturbance, attributes associated with stream networks, and various landscape disturbance layers.  We conducted analyses identifying dominant environmental trends and mitigation issues within each 8-digit HUC.  Based on regional trends and common environmental constraints, we develop a geo-spatial hierarchical assessment tool that identifies potential environmental impacts based on the location and the user-defined extent of alteration related to hydropower.