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. This report describes the concept for developing the Tier 1 impact assessment, or 'disturbance scores' for the lower Columbia River floodplain. The 'Tier 1' terminology is no longer being applied in the greater Habitat Restoration Strategy, with the data set now referred to as simply the 'Landscape Disturbance' model. The GIS based data set was developed by the Battelle Pacific Northwest National Laboratory, for the Lower Columbia Estuary Partnership. Funding was provided by the Bonneville Power Administration.