The Ralph and Goldy Lewis Center for Regional Policy Studies

Caltrans District 7 freeway corridors require evaluation to determine their capacity to support effective, high-capacity regional bus-based trunk service. While freeways serve as the region’s mobility backbone, transit performance remains uneven due to institutional fragmentation and infrastructure constraints. This analysis identifies the conditions required for reliable, all-day service and applies them to a regional screening framework.The study uses a comparative case study approach, examining U.S. freeway corridors and international high-capacity busway systems using a consistent unit of comparison: Type 1 all-day trunk services. Quantitative performance indicators, including ridership, reliability, and cost efficiency, are paired with agency documentation and practitioner input to identify recurring drivers of performance.Five core factors govern corridor outcomes: right-of-way continuity, trunk consolidation, station interface and throughput, governance coordination, and terminal capacity. Right-of-way continuity defines the operating baseline, while station interface often becomes the primary constraint as demand increases.These findings are applied through a District 7 screening framework that evaluates segments based on Market Potential and Implementation Feasibility. The framework can be used to prioritize corridors for deeper technical study. Implementation requires coordinated governance across operators and early corridor-level branding to maintain service clarity and network legibility.