Repairing, removing and retrofitting barriers (e.g., installing fish ladders) are seen as some of the most effective and cost-efficient means of habitat restoration available. However, in spite of the potential benefits, surprisingly little has been done with regard to the development of quantitative/analytic planning methods for prioritizing barrier repair and removal decisions. Our presentation will summarize efforts under way since 2006 to bring together state and federal agencies and non-governmental organizations to build an inventory of fish passage barriers in Maine. We will present systemic methods for prioritizing the repair or removal of fish passage barriers for diadromous and resident fishes. Working with a variety of partners, we have developed GIS tools and budget-constrained optimization models for deciding which barriers to repair or remove in order to maximize habitat availability for stream resident fish and diadromous fish species
