Thom, R., E. Haas, N. Evans and G. Williams. 2011. Lower Columbia River and Estuary Habitat Restoration Prioritization Framework. Ecological Restoration 29: 94–110.

Authors present a two-tiered framework for identifying restoration projects that maximize return on investment.  The target area for this study is the historic floodplains of the Lower Columbia River (river kilometer 0 to 235).  In Tier I, a GIS is used to analyze anthropogenic impacts caused by dikes, agricultural activities, overwater structures and flow restrictions.  These impacts are quantified by a formula and then stored in the GIS, which assigns a spatial context to the impacts.  In Tier II pre-screened restoration projects are evaluated based on cost, estimated functional change, site size and probability of success.  The second tier is not GIS based.  This framework allows managers to identify impacted areas, locate potential sites and then prioritize the sites for restoration. Controlling factors or indicators of degradation that were examined in this framework are: hydrology (river, watershed and site scales), sediment quality, water quality, light, sediment dynamics, physical disturbance, depth/slope and non-native species.  Authors note that sufficient data for all of these indicators was not available.  They recommend continuously collecting data, documenting knowledge learned and refining the scoring process as knowledge increases.  This framework allows us to better understand the habitat needs of target species, track restoration progress and share information.

Figure 2. Examples of hydrologic context applied to sites according to presence of at least 50 m Columbia riverfront shoreline and slope class (flat/steep). Width of map ~15km.