Regional analysis for transportation corridor planning

Developing regional assessments of environmental needs can help streamline the environmental-review process for transportation projects, thus leading to faster and less-costly reviews and more effective biological or ecological mitigation. This study is a demonstration of a rapid-assessment approach using a high-resolution vegetation map derived from agency data to model 12 endangered or threatened species’ potential occurrence on 6638 polygons. Those units, occurring on 44 capacity-improvement sites along the 315-km of State Highway 99 in the study, were classed to measure their degree of similarity, thus permitting estimates of the potential for multi-project mitigation planning.