State Water Resources Control Board adopts statewide Caltrans stormwater permit, approves time schedule order

The State Water Resources Control Board on June 22 voted unanimously to adopt a proposed statewide municipal stormwater National Pollutant Discharge Elimination System (NPDES) permit and an accompanying time schedule order for the California Department of Transportation (Caltrans).

Mary Boyd, project manager for the Division of Water Quality's municipal stormwater unit, told the board the permit package reflects four years of development, public workshops and responses to a 60‑day comment period on the 2021 draft. "We placed TMDL requirements in a time schedule order," Boyd said, and staff added statewide trash provisions, more sensitive laboratory requirements, and electronic reporting to the Stormwater Multiple Application and Reporting Tool (SMARTS).

The permit replaces the prior Caltrans permit and includes seven attachments covering definitions, stormwater management plan requirements, TMDL implementation, trash controls, monitoring, and reporting. Key changes include a requirement that Caltrans produce retrofit plans and asset inventories, a clarified cooperative‑agreement definition to avoid double counting, a 30‑day public comment period for TMDL compliance plans, stricter site inspection reporting (including dates, inspector names and photos, and 60‑day submittal), and revised trash milestones that require phased progress to full‑capture…