CA AB1798

Requires the Department of Transportation and State Water Resources Control Board to jointly develop a programmatic environmental review process to prevent 6PPD and 6PPD-quinone (toxic tire wear chemicals) from entering salmon and steelhead trout bearing waters.

Mandates five pilot projects in San Mateo, Contra Costa, Sonoma, Humboldt, and Nevada counties by December 31, 2026 to study effectiveness and cost of bioretention and biofiltration systems along state highways.

Requires the department to create a map of locations where it discharges stormwater into salmon and steelhead waters, including overlays of fishery information, vehicle miles traveled, and drainage outlets.

Establishes December 31, 2037 as the deadline for the department to eliminate all discharge of 6PPD and 6PPD-quinone into salmon and steelhead trout bearing surface waters, with a strategy due by December 31, 2027.

Mandates all information provided to the State Water Resources Control Board be made publicly available through the board's stormwater data collection system and requires government-to-government consultation with tribal communities.