Post-project appraisal of year one Re-vegetation performance at the Nathanson Creek Restoration Project, Sonoma County, CA
The Nathanson Creek Parkway and Preserve project spans a 1,000 foot reach of Nathanson Creek, a tributary to Sonoma Creek next to the Sonoma Valley High School grounds (see Appendix A Figures 1-6). The Sonoma Ecology Center (SEC) entered a contract with the city of Sonoma after the creek flooded in 2006 and installed plants between November 2009 and May 2010. The purpose of this project is to analyze plant survivorship data after 1-year of growth and to establish baseline data on the channel morphology for future restoration monitoring. We recorded total plant survivorship, created 5 cross-sectional transects (one every 200ft.), and recorded the plants growing along each transect. We also documented incidents of vandalism and overall site conditions.
After one year, the restoration site showed 63.6% survivorship among the flora that were planted plus broadcast seeding of the native grass Blue wildrye (elymus glaucus). This survival rate does not meet the 80% standard set by the SEC for its restoration efforts. Without baseline morphology data, it is too early to come to any conclusions on the relationship between the planting and the channel morphology without, but observations suggest that the re-vegetation has done little to decrease back erosion or mitigate a future flood event.