To dig a utility trench in the right-of-way of San Mateo County's unincorporated districts requires an encroachment permit from the Department of Public Works.
- Behind walkways, paths, sidewalks - $130
- For minor trenches (eg: pothole, digouts) in the travel way - $391
- For a major trenches (eg: linear work which is wider than the Right of Way width) up to 100 feet total length - $1957
- For a major trenches greater than 100 feet - $1957 +0.50/foot of trench