Is Drive Clean Across Texas responsible for the lowered speed limits in Houston?
No. The environmental speed limits are one of the actions developed as part of the State Implementation Plan (SIP) for the Houston-Galveston (HG) and Dallas-Ft. regions to reduce pollution. These lower speed limits are incorporated into the SIP by the Texas Commission on Environmental Quality (TCEQ), and approved by the EPA. Solutions such as reduced speed limits are a necessary part of the plan that the state must develop in order to comply with federal air quality standards.