Analysis of Projected Replacement and Costs for Potential Aquatic Barriers Maintained by MaineDOT

Recent discussions around State and federal stream crossing regulations have focused on resolving existing barriers to fish movement created by culverts and struts associated with transportation infrastructure. Approximately 30% of Maine has been surveyed for stream barriers through the joint efforts of state and federal fisheries agencies and non-government organizations, which have mapped this data via geographic information system (GIS). These same entities are currently working toward prioritizing identified barriers according to potential habitat value and species status. The resulting database contains location information, but does not differentiate crossings for which the state is responsible from those under local or private responsibility. This lack of distinction makes it near to impossible to quantify specific future costs to Maine Department of Transportation (MaineDOT) other than on a crossing by crossing basis. Because the database does not account for the age of individual structures, it is not possible to determine if barriers have been exacerbated by recent replacements and rehabilitations or if the barriers to fish movement are historic and therefore likely to be remedied in the relatively near future through standard MaineDOT maintenance protocols.