Watercourse Modification Permits

Watercourse Modification Permits are issued under the City of Mill Valley Municipal Code, Section 17.06.110.

Watercourse Modification Permit is required to:

• Discharge into or connect a pipe to a watercourse
• Modify the natural flow of a watercourse
• Plant in or remove material from a watercourse (including its banks)
• Construct in, alter, enlarge, connect to, change or remove any structure in a watercourse.

To apply, please fill out and return the Watercourse Modification Permit Application.

Most Watercourse Modification Permits require plans, hydraulic calculations, and prior project approval by the Regional Water Quality Control Board and Army Corps of Engineers.

If you have any questions, please contact the Public Works Department at (415) 388-4033.