SAGE was hired to evaluate and update standard drawings for repair and rehabilitation of our client’s canals, which convey water for hydropower systems throughout California. The objective was to develop a unified set of plans, specifications, and special provisions that can be used system-wide, and address a wide-range of canal capacity and topographic conditions.
SAGE performed research that included benchmarking “standards of practice” and “best practices” used by large agencies for the design and operation of lined conveyance facilities. We visited several different watersheds within our client’s service area to better understand the wide range of canal capacity, and geologic and topographic conditions.
To accommodate the range of canal flows (30 to 800 cfs) and geometries within the system, multiple liner designs were developed. For canals where leakage is not a concern, jointed liners consistent with ACI-318/ACI-360 were developed. For canals in locations that are sensitive to leakage, water-tight liners were designed in accordance with ACI-350. The percentage of steel rebar for shrinkage and temperature reinforcement was reduced through the use of macro- and microsynthetic fiber reinforcement based on fiber reinforcement design research. This improves overall concrete/shotcrete performance and constructability in remote locations.
SAGE developed standards plans, specifications, and special provisions for construction of new canal liners during annual maintenance activities. The standard drawings incorporate alternative materials, such as synthetic fiber-reinforced shotcrete, to improve constructability in remote locations. We developed planning checklists and a decision-matrix flowchart to facilitate standards implemented by the clients’ operations and maintenance personnel.
SAGE currently serves as Engineer-of-Record for multiple annual maintenance outages for canals ranging in capacity from 40 to 850 cfs, and with annual budgets up to $10M. Our engineers provide construction support of multiple concurrent sites during 7-day-a-week outages to address modifications to the standard details due to site-specific conditions and unexpected findings during the limited duration outages. Our staff also participate in annual condition assessments of existing shotcrete and gunite canal linings in support of our client’s Asset Management and Planning Departments.