Environmental Mitigation

In consideration of goals to accelerate the development and deployment of sustainable hydropower technologies, the Environmental Mitigation effort addresses the uncertainties of environmental requirements included as license conditions by FERC. The goal of the Environmental Mitigation task, as part of the larger NHAAP effort to provide hydropower development analysis tools, is to (1) develop a database of mitigation included in the FERC licenses of non-federal hydropower facilities, and (2) develop predictive models that can be used to anticipate mitigation scenarios based on project location and design characteristics.

Mitigation Database

Mitigation requirements were compiled from FERC hydropower licenses issued from 1998 through 2013. Each mitigation record is associated with a unique plant identifier, state, hydrologic unit code, and a mitigation classification. Database development methodology and mitigation assessment reports are forthcoming. Summarized mitigation data at the 2-digit hydrologic unit code (HUC-02) level are available on NHAAP’s HydroGIS Viewer. Mitigation data are available as a Microsoft Access database and in Excel format below (note that critical infrastructure information such as location coordinates have been removed from publicly accessible data).

Mitigation Prediction

Mitigation requirements from the mitigation database were linked to predictor variables using GIS. General categories of candidate predictors included facility characteristics, presence of sensitive fish species, human dimensions, hydrology, landscape characteristics, location, and stream network attributes. Predictive models were built using boosted regression trees for mitigation types that were required at greater than 5% of the plants in the mitigation database. Predictions of mitigation requirements can be applied to relicensing sites, non-powered dams, or potential new sites.