Ecological Assessment Process and Credit System for Highway Capacity Projects

This Strategic Highway Research Program capacity project (C06B) study developed a cumulative effects and alternatives assessment (CEAA) process for highway capacity projects within an integrated ecological and transportation planning framework called the Ecological Assessment Framework. This framework created tools to support the principles of Eco-Logical: An Ecosystem Approach to Developing Infrastructure Projects. Existing ecological assessment and ecosystem crediting tools were surveyed and assessed, and a new template for cumulative effects and alternatives analysis was developed. The resulting process includes methods for enhancing data needed to reach early agreement with regulatory agencies under the Endangered Species Act and the Clean Water Act. Guidance for developing function-based ecosystem crediting tools to meet regulatory requirements and to promote environmental stewardship goals is also provided. The CEAA process was piloted in three states to compare results between the new method and traditional methods. Initial results and case studies show that integrated ecological and transportation planning can expedite capacity project delivery and improve environmental outcomes. The CEAA process and supporting tools, case studies, and data sources will be integrated into the new Transportation for Communities: Advancing Projects Through Partnerships website.