Urban expressway corridors can be enhanced to accommodate a wider range of transportation including new public transit types and pedestrian and cycling pathways, and urban and ecological services such as parks and bioretention for stormwater runoff treatment. This research-design thesis identifies green infrastructure as a flexible design tool to improve urban expressways in regards to stormwater runoff, traffic, safety, transit, public health, economy, and community. After discussing new automobile technology that could organize traffic and reduce congestion on urban expressways, this thesis examines the current state of highway stormwater treatment and explores potential improvements. It then identifies green infrastructure as a flexible design tool to convert urban expressways into multi-modal transportation landscapes with improved stormwater control and other environmental, social, and economic urban benefits. A design application on the Atlanta downtown connector tests the strengths and weaknesses of using green infrastructure as such a strategy.