Grading, Drainage, & Storm Water
Grading, Drainage, & Storm Water is a section within the Engineering and Construction division that reviews and issues permits related to grading, drainage and storm water for properties in unincorporated Sonoma County. Grading, Drainage, & Storm Water ensures that construction and grading do not cause flooding. Grading is the excavation (cuts) and placement (fill) of earth material by artificial means. Storm water is any storm water runoff, snow melt, or surface runoff.
- Email: PermitSonoma-Engineering@sonoma-county.org
- Phone: (707) 565-2268
- Fax: (707) 565-1103
End of Extended COVID Permit Expiration Date
In order to support the difficulties the COVID-19 pandemic brought to the community, Permit Sonoma offered customers a two-year extension above and beyond the regular timelines for various ministerial applications and permits. The conditions attributing to the local emergency no longer exist and the Board of Supervisors is rescinding the local emergency as of May 16, 2023. As such, the policy extending the expiration dates will sunset effective May 17, 2023.
This change does not affect permits that have already been extended. All applications received beginning May 17, 2023 will be valid for one year, and the COVID-19 extension will not be applied.
Flood Management Design Manual Announcement
Sonoma Water’s Board of Directors adopted a resolution approving the Flood Management Design Manual (FMDM) to provide guidance and criteria for the conveyance of storm water. The FMDM is a significant update to the existing criteria and will replace the current Sonoma County Water Agency Flood Control Design Criteria (FCDC).