Transportation Control Measures
Transportation Control Measures (TCMs) are identified by air quality management plans and implementation plans to reduce emissions or concentrations of air pollutants from transportation sources by reducing vehicle use, changing traffic flow, or congestion conditions. SCAG works closely with the CTCs and Caltrans to ensure timely implementation of committed TCM projects in the region. Substitution of individual TCMs follows the process specified in the federal Clean Air Act (CAA) section 176(c). Section 176© of the CAA allows for the substitution of individual TCMs if certain conditions are met. The CTCs and/or project sponsors notify SCAG when a TCM project cannot be delivered or will be significantly delayed. SCAG and the CTCs identify and evaluate possible replacement measures for individual substitutions, with consultation from the Transportation Conformity Working Group (TCWG), which includes members from all affected jurisdictions, federal, state and/or local air quality agencies, and transportation agencies.
Air quality plans and corresponding documents are maintained and available on the California Air Resources Board website.
TCM Substitutions
- 2022
- Orange County Transportation Authority (OCTA) Transportation Control Measure (TCM) Substitution Report (FTIP IDs ORA130099 & ORA030612) - Orange County Transportation Authority (OCTA) Transportation Control Measure (TCM) Substitution Report (FTIP IDs 10254, ORA050 & ORA051) 
- 2018
- Draft Orange County Transportation Authority (OCTA) Transportation Control Measure (TCM) Substitution Report for Public Review 
- 2016
- OCTA TCM Substitution 
- 2015
- Los Angeles County Metropolitan Transportation Authority (Metro), Riverside County Transportation Commission (RCTC), and San Bernardino Associated Governments (SANBAG) TCM Substitutions 
- 2013
- Replacement of a Bus Purchase Project with Traffic Signal Sychronization Projects in Orange County (OCTA) 
- 2010
- State Route 60 HOV Lane Conversion of Moreno Valley, Riverside County (Caltrans) - Replacement of Bus Rapid Transit (BRT) Projects with Signal Sychronization Projects in Orange County (OCTA)