A Conceptual Framework for Assessing Impacts of Roads on Aquatic Biota

Abstract

Abstract Roads are pervasive in modern landscapes and adversely affect many aquatic ecosystems. Conventional environmental assessments of roads focus on construction impacts but ignore subsequent impacts. A comprehensive framework for considering all impacts of roads would enable scientists and managers to develop assessment tools that more accurately inform stakeholders and policymakers about the biological consequences of road building. We developed a two-dimensional framework to organize impacts of roads on aquatic biota. One dimension recognizes three phases of road development, each with distinctive ranges of spatial and temporal scales. The second dimension recognizes five classes of environmental impacts associated with road development. The framework is useful in evaluating the completeness of assessments and in identifying gaps in scientific knowledge. We applied the framework to a draft environmental impact statement (DEIS) for a proposed interstate highway to illustrate which road impacts are t...