About
Sediment is removed approximately every five years from Novato Creek, Warner Creek, and Arroyo Avichi between Diablo Ave and the SMART railroad crossing downstream of Rowland Way.
The most recent removal was between July and October 2020. Sediment was beneficially reused on a proposed future ecotone levee in Deer Island Basin and in Heron’s Beak Pond. This helped prepare these basins for future restoration efforts. This work was completed for approximately $1.6 million.
For 2026, the plan is to integrate the sediment removal with the Deer Island Bird Ponds Restoration Project, which can beneficially reuse the sediment as part of that project to build eco-tone levees and raise site grades which benefits both projects and should lower costs for implementation.
A study consisting of a hydraulic model of the sediment removal has been conducted to evaluate the effectiveness of the ongoing sediment removal efforts. The study identified that the permitting and construction costs for the temporary benefit of sediment removal (as it needs to be done approximately every 5 years to remove new sediment buildup) does not make this a cost-effective option in the long term. The Flood Zone 1 Advisory Board is evaluating potential projects for the long term that may be more effective at protecting downtown Novato, such as tide gates and pump stations.
Timeline
- Design - 2025
- Permitting and CEQA - 2025
- Construction - 2026
Status
Under the existing Programmatic Maintenance permits, the District evaluated the need for smaller scale sediment removal and vegetation management in 2023 and 2024 and it was determined not to be needed. The District is working with the Flood Zone 1 Advisory Board to recommend rescheduling the next full sediment removal to 2026.