Yolo County, CA Environmental Rules: Vehicle Idling Restrictions (2026)

Under the Cache Creek Area Plan In-Channel Ordinance (Title 10, Chapter 3), firms and individuals holding an approved in-channel sand and gravel extraction permit must keep internal combustion engines tuned to manufacturer specifications and properly maintained to minimize oil and fuel leakage. Layered onto that maintenance duty is a flat ten-minute cap: no vehicle or piece of equipment working the channel may sit idling longer than ten minutes at a stretch. The rule sits inside Sec. 407, "Hazards and Hazardous Materials," alongside requirements for a Storm Water Pollution Prevention Plan on qualifying projects, a chemical spill prevention and emergency plan for long-term jobs like extensive erosion control or gravel removal, and worker training in spill response.

Operators must also file a Hazardous Materials Plan and, where required, a Spill Prevention Countermeasure Contingency Plan with the Yolo County Environmental Health Division before any in-channel work begins. Any fire, explosion, spill, or slope failure at the site triggers an immediate notice to the Director and the Yolo County Office of Emergency Services, followed by a written report within thirty days covering the facts, corrective measures taken, and steps to prevent recurrence. The idling cap and its neighboring hazardous-materials conditions were carried forward as amended by Ord.

1518, effective February 13, 2020. Because this chapter governs only the approved in-channel aggregate mining program along Cache Creek, the ten-minute limit binds mining permittees and their contractors working the streambed; it is not a general anti-idling rule for cars, trucks, or equipment elsewhere in unincorporated Yolo County.