Solano County, CA Environmental Rules: Erosion Control (2026)

Chapter 31 of the Solano County Code requires a grading permit from Solano County Public Works for any work that involves significant excavation, fill, or land leveling, with a narrow exemption: fill is exempt only when it does not exceed 50 cubic yards on any one site, is less than 5,000 square feet of surface area, less than 3 feet vertical depth, placed on a slope no steeper than 7:1, does not create a slope steeper than 2:1, does not change off-site drainage patterns, will not be used for structural support, and is promptly stabilized or revegetated to prevent erosion. All other grading requires a permit. A grading permit must include an approved erosion-control plan; conditions imposed by the Director of Resource Management can include drainage provisions, revegetation requirements, sediment basins, fiber rolls, silt fencing, hydroseeding, and seasonal limits on disturbed-soil exposure (October 15 – April 15 wet season). Projects disturbing 1 acre or more must also obtain coverage under the State Construction General Permit and submit a SWPPP (see Stormwater). For agricultural land leveling and ranch roads, Chapter 31 still applies but the County coordinates with the Solano Resource Conservation District on best management practices. Permits in Suisun Marsh primary management area carry additional review under the County's Local Protection Program for the Marsh.