Lower Columbia River and Estuary Habitat Restoration Prioritization Framework

Abstract

The Restoration Prioritization Framework was designed as a decision-making tool for the Lower Columbia River Estuary Partnership, to help identify the highest-priority sites for restoration. The underlying concepts are derived from regional applications of aquatic restoration theory. The framework uses the conceptual model that physical controlling factors (e.g., light, temperature, hydrology) drive the formation and maintenance of habitats and their ecological functions, and that act on the controlling factors. The framework is two tiered and comprises 1) an overview of the concepts and description of framework tools; 2) a spreadsheet containing detailed data, formulas, and workflow for the actual site prioritization; and 3) a geographic information system (GIS) database containing source and processed geospatial datasets. In Tier I, the framework uses a GIS-based approach to evaluate impacts from a variety of human stressors such as diking, agriculture, overwater structures, and flow restrictions. Data processing derives priority scores, which are then relinked to the geographic sites in the GIS. In this manner, all of the data and tools employed can be analyzed and queried in a geospatial context. In addition to the core impact assessment, the framework includes tools to incorporate information on hydrologic connectivity and existing function into the priority screening. Specific restoration project proposals are evaluated in Tier II, using information on cost, expected functional change, site size, and predicted probability of success. Using this framework, the Lower Columbia River Estuary Partnership can screen for impacted areas, prioritize areas based on desired ecological criteria, and evaluate selected projects.