Zero-Emission Truck Adoption at California Warehouses: Who Is Adopting, Who Is Left Behind, and Why?

The South Coast Air Quality Management District’s (AQMD) Warehouse Actions and Investments to Reduce Emissions (WAIRE) Program is the nation’s first indirect source rule (ISR) for warehouses, a type of rule that holds facilities responsible for pollution from the vehicles that visit them. It requires nearly 4,000 warehouse operators across Southern California to annually take actions that reduce emissions, such as acquiring or using a zero-emission (ZE) truck. However, roughly 60% of regulated operators are estimated not to own the truck fleets visiting their facilities, creating a complex regulatory challenge: operators must influence emissions from trucks they do not directly control. This project investigates which operators are successfully facilitating ZE truck visits under WAIRE, the methods they use, and whether compliance patterns are equitably distributed across environmental justice (EJ) communities. The project combines quantitative analysis of compliance actions — linked to CalEnviroScreen 5.0 scores by location and EV charging infrastructure data — with interviews of warehouse operators. Findings will reveal whether ZE truck adoption is concentrated at certain facilities, leaving the most-impacted EJ communities with continued diesel exposure, and what barriers prevent contracted carriers from adopting ZE trucks. Results may guide mitigation fee investments and support policy discussions on ISR expansion by providing evidence on how ZE adoption happens under ISRs.