Post-project appraisal of Martin Canyon Creek restoration
Located in Dublin, California, Martin Canyon Creek is a small tributary draining 1.08 square miles in the Alameda Creek watershed. In 1999 a restoration project consisting of gradient control and bank stabilization structures was completed. We conducted a post-project appraisal of the Martin Canyon Creek Restoration Project, comparing current conditions with the project’s listed goals and as-built conditions. We surveyed a longitudinal profile and a selected cross section to compare current channel slopes and geometry with pre-project and as-built conditions. In addition, we took photos of grade control and bank stabilization structures at established photo monitoring points and compared them with as-built photos to qualitatively compare and evaluate performance of structural components of the project. Grade control structures appear to be stable and performing as designed, with significant local sedimentation upstream of most grade control structures. Grade Control Structure #4, however, shows significant signs of deterioration and could be prone to failure without maintenance in the near term. We suspect that the deterioration of this structure is related to its location in a bend and a high upstream channel slope, however further research is required to fully understand the performance of this structure. Bank stabilization structures are also performing in terms of protecting neighboring structures, although some show signs of deterioration. Overall the dynamic equilibrium slope that guided the design of the project appears to have been achieved with fewer structures than originally proposed.