Butano Creek Channel Reconnection and Resilience Project
Pescadero Marsh Natural Preserve is a special place with a very high level of community, public agency, and NGO interest in its management. Home to many state and federally listed threatened and endangered species, resource management for the marsh can also have direct implications for the adjacent community that was built in its floodplain in the early 1800s.
Historic land use in the watershed, including logging and channelizing creeks, road construction, agriculture, and development (including a town in the floodplain) dramatically increased the volume of sediment entering the marsh. Routine dredging in the marsh and along Butano Creek historically conducted by local farmers ended when the State of California acquired the marsh and lagoon in 1974 as a natural preserve, along with environmental regulations, notably: Endangered Species Act (1973), Clean Water Act (1977), and California Coastal Act (1976).
Lower Butano Creek, where it runs through the marsh, has completely filled in with sediment. This blocks threatened steelhead trout and endangered coho salmon from the entire Butano watershed for spawning, rearing their young, and finding critical refuge during storms and droughts. In addition, annual mass deaths of steelhead in the marsh from poor water quality have garnered significant media attention, even as far away as the Washington Post. Chronic flooding of the main road into Pescadero cuts the community off from emergency services and the primary access to State Highway 1. There used to be 14 feet of clearance under the bridge. Now a sediment filled channel exacerbates flooding and road closures. In addition to safety and emergency response, this severely impairs commercial activity in town. Even the perception that the road may be closed deters people from coming to town, resulting in economic impacts.
The RCD has been working for years to find solutions to these problems, engaging engineers, scientists, community members, and representatives from a number of different agencies. In 2017, the RCD was awarded funding to re-establish 8,000 feet of the historic creek channel, remove 45,000 cubic yards of sediment, and re-use the dredge material to fill historic human-made pits to restore 28 acres of degraded marsh.
The project will:
- Restore access to 10.1 miles of Butano Creek for threatened steelhead trout and endangered coho salmon by reestablishing unimpeded fish passage for a decade or more.
- Reduce risk to the community associated with flooding at Pescadero Creek Road by reducing the extent, duration and frequency of flooding.
- Improve the likelihood of salmonid survival by reducing the risk and/or severity of fish kills through
- creating access to oxygen-rich freshwater refuge during time of low water quality; and
- reducing anoxic conditions by preventing percolation and movement or freshwater from Butano Creek through and across the marsh.
Additionally, the project may:
- Improve or create habitat for freshwater marsh species (e.g. California red legged frogs and San Francisco garter snakes) from beneficial re-use of dredge material.
- Improve survival of salmonids by strategically placing dredge material to
- reduce the area of the marsh that is creating anoxic conditions; and/or
- reduce the ability of anoxic water to rapidly flood the lagoon; and/or
- reduce opportunities for fish to seek refuge in areas of poor water quality.
- Provide critical data to inform ecological restoration of the marsh.
While the project is designed as a “win-win” to address a discrete set of issues (fish passage, flooding, and water quality), it will not solve all or most problems in the marsh and lagoon, restore all function of the marsh and lagoon, or eliminate flooding in the community. Specifically, it will not:
- Restore habitat for all marsh species.
- Provide comprehensive ecosystem restoration.
- Remove the community from the floodplain or eliminate flooding to the community.
- Address any flooding from Pescadero Creek.
- Eliminate all flooding from Butano Creek.
To accomplish these goals, the project will excavate and dredge as needed to re-establish 8,000 feet of the historic creek channel, remove 45,000 cubic yards of sediment, and re-use the dredge material to fill historic human-made pits to restore 28 acres of degraded marsh.
- Summer 2018: CEQA completed
- Fall 2018: designs and permitting completed
- September 2018: Phase 1 (vegetation removal) completed
- October 2018- January 2019: Public bid process and contractor selection
- Spring 2019: Phase 2 (more vegetation removal)
- Summer-fall 2019: Phase 3 (excavation, dredging, and berm construction)
For more details about the status of each project task and a detailed project schedule, review this GANTT chart.
- Project Designs and Basis of Design Report (October 2018)
- CEQA Documents
- Notice of Determination (June 28, 2018)
- RCD Board Resolution Approving the Mitigated Negative Declaration and Adopting the Mitigation Monitoring and Reporting Program (June 27, 2018)
- Memo to Board of Directors Regarding Comments Received during the Public Review Period (June 22, 2018)
- Final Mitigation Monitoring and Reporting Program Summary Table
- Initial Study/ Mitigated Negative Declaration (May 2018)
- PowerPoint Presentations
- California State Parks
- San Mateo County
- National Atmospheric and Oceanic Administration (NOAA)
RCD Contact: Kellyx Nelson