Best Practices: Foothill Transit’s Strategy to Deploying Zero-emission Technologies and Managing a Mixed Fleet

Operating a mixed fleet of compressed natural gas (CNG), battery-electric and fuel cell electric buses (FCEB) buses has positioned Foothill Transit as one of the nation’s most innovative public transportation agencies in the country. Serving the San Gabriel and Pomona Valleys from its headquarters in West Covina, Calif., the agency has spent more than a decade testing and integrating multiple propulsion technologies while balancing operational reliability, environmental sustainability and fiscal responsibility. 

Foothill Transit first emerged as a leader in zero-emissions transit when it introduced fast-charge battery-electric buses (BEBs) in 2010, the first in the nation to do so. The expansion of the electric fleet occurred slowly while the agency continued to test the new technology, relying on a large CNG fleet for dependable daily service. By 2020, the agency operated approximately 327 CNG buses alongside 33 BEBs. This diversified approach allowed the agency to evaluate performance in real-world conditions instead of relying on a single technology strategy. 

One of Foothill Transit’s strongest business practices has been phased deployment. Foothill Transit introduced zero-emission technologies incrementally, deploying into myriad ridership environments and along both short local service and longer commuter style routes. This reduced operational risk and allowed maintenance staff, operators and planners to adapt to new fleet parameters gradually.  

Infrastructure planning has also been critical to thorough deployment evaluation. The agency invested in extensive charging systems, in partnership with local utilities, and upgraded electrical infrastructure, later developing hydrogen fueling capabilities at the agency’s Pomona Operations and Maintenance Facility. In 2021, Foothill Transit approved contracts for hydrogen fueling infrastructure and FCEB buses, further diversifying its fleet strategy. By 2022, the agency launched Los Angeles County’s first FCEB buses into revenue service and eventually had the largest FCEB fleet in the country. These investments demonstrate a key best practice for mid-sized transit agencies: infrastructure must evolve alongside fleet procurement, not after it. 

Another important lesson from Foothill Transit’s experience is the value of operational flexibility. BEBs offer significant emissions reductions and lower fuel costs, but they can face range limitations, considerable charging downtime compared to the CNG equivalents and parts availability challenges. Instead of abandoning zero-emission goals, the agency diversified into FCEB technology, which offers longer range and faster refueling—equivalent to CNG—for demanding routes.   

The most challenging disparity has been cost in both available fuel and in the vehicles themselves, with FCEB buses costing $1.6 million compared to half that price for a CNG vehicle. Here, the most important best practice is flexibility. With this significant cost differential, Foothill Transit has had to pause FCEB purchasing. 

Strong grant management and partnership development have been key at all steps of this transition. Foothill Transit leveraged federal and California climate funding programs and nurtured meaningful partnerships with manufacturers, fuel providers and engineering firms, which has allowed the agency to reduce financial exposure while staying committed to a zero- emissions future.  

Thus far, the best path forward has been flexibility and not reliance on a single propulsion technology. CNG buses can continue providing dependable backup capacity during infrastructure transitions. BEBs are ideal for shorter urban circulators and predictable routes. Hydrogen FCEB buses can support longer regional service where charging constraints remain challenging. 

Moving forward, Foothill Transit will continue expanding its hydrogen and battery-electric fleets while using data-driven route analysis to determine the best technology for each service type. Continued investment in workforce training, predictive maintenance systems and scalable fueling infrastructure will help ensure operational reliability and long-term financial sustainability.