• Supplemental site topographic surveying
• Peak flow assessment and shear stress analysis
• Hydraulic and geomorphic analysis and design
• Regulatory agency permitting support
• Engineering plan and specifications preparation
• Field construction supervision and post-construction maintenance and monitoring

Clearwater Hydrology (CH) prepared restoration designs for four intermittent and two ephemeral channels, and assisted in the design-construction of three off-channel wetlands at the Big Rock Ranch complex in western Marin County. These Nicasio Creek headwater watersheds had been subject to heavy cattle grazing, including unfettered channel access, which had degraded channel stability and precluded the development of a riparian corridor. The extensive restoration efforts provided mitigation credits for a reservoir expansion and facilities construction. One of the stream restorations involved re-alignment of a highly unstable (i.e. landslide-riddled) channel reach, located downslope of a newly constructed septic system leachfield. The design channel components comprised rapid-pool and step-pool morphologies, utilizing boulder step-pools and native material revetments, and coupled with geomorphically-appropriate flood terraces. CH also supervised the field installation of the restorations during the summers of 2001 and 2002.

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