Permanente Creek Restoration Project

The Permanente Creek Restoration Project is ambitious in scope: it will restore over 1.5 miles of creek and substantially improve conditions on dozens of acres of creek bed.

The Permanente Creek Restoration Project involves stream restoration on approximately 9,000 feet of Permanente Creek. The six-year project will remove legacy infrastructure on the creek installed over the century of mining operations on the Permanente Quarry site. In addition to restoring the channel site, the project will also remove invasive species, install native riparian habitat, and create additional pool habitat providing suitable fish passage through these sections of Stevens Creek. This work will be completed based on current stream restoration approaches and engineering, returning the ephemeral stream to a more pre-disturbance condition with an emphasis on creating a richer, more stable environment around the creek that reflects modern standards and community expectations.

The restoration project has been under planning and environmental review for more than a decade. Environmental review for this project was completed in May 2024. The full permitting process was completed in June 2025, making way for Heidelberg Materials to begin work on the creek in July 2025. The work will commence on the following yearly timeline over the next six years:

Scope of Work

Year 1

• Concrete-lined channel: Install native riparian vegetation along the southern bank at locations void of native species along ~1,575 linear feet of channel.
• Channel widening: Perform ~2,450 linear feet of grading to create an inset floodplain bench and reduce the existing road width.
• Remove one culvert and construct an open channel segment.
• Remove sediment from the tributary and fan along the southern bank of Permanente Creek.
• Revegetate all areas disturbed by construction.

• Rock Pile Area: Perform grading activities from ~800 linear feet.
• Revegetate all areas disturbed by construction.

Year 2

Year 3

• Rock Pile Area: Remove two culverts and pond 13 infrastructure.
• Construct a maximum of ~1,345 linear feet of restored channel.
• Revegetate all areas disturbed by construction.

• Channel widening: Perform ~1,775 linear feet of grading to create an inset floodplain bench and reduce the existing road width.
• Remove two more culverts and construct open channel segments.
• Revegetate all areas disturbed by construction.

Year 4

Year 5

• Remove the old crusher foundation.
• Material Removal Area: Perform grading activities along ghe haul road and Pond 4 access road. Construct an access road along the channel.
• Revegetate all areas disturbed by construction.

• Material Removal Area: Continue grading activities to restore the channel.
• Revegetate all areas disturbed by construction.

Year 6

The below illustrations are provided as an example of the work that will be done on the site, and do not refer to any exact work-site areas as part of the Permanente Creek Restoration process.