Flow Science originally performed a hydraulic and pressure surge analysis for the Lake Perris Bypass Facility for Lake Perris Pumpback and Casa Loma Canal modes of operation between 1991 and 1993. FSI then reanalyzed the system in 2006 as a result of changes to the pumping and piping configurations. Surge computations for pump and turbine operations were verified by Metropolitan field testing (see section following). Analysis also involved 60,000 ft of 144-inch diameter DWR Santa Ana Valley Branch of California Aqueduct. A unique surge protection device was developed to protect the Bernasconi tunnel.