The Freshwater Fisheries Society (FFS) of BC developed an efficient air lift reuse system for circular tanks that is being implemented at all of their hatcheries. As part of this implementation, FFS contracted with McMillen Jacobs to provide the engineering design to accommodate the new improved technology. The hatchery required modification to their existing infrastructure to accommodate nine new circular tanks of varying size. The water supply piping and treatment required modifications to provide sufficient head to supply the circular tanks. The existing water supply system consisted of several wells providing the bulk of the water to the hatchery. The well water required degassing and has radon issues associated with it.
The project consisted of developing layouts and routing for the circular tanks and piping to be installed within the existing raceways by removing the interior walls and utilizing the existing footprint within the raceway building. McMillen Jacobs evaluated the operations of the existing system on site and determined site constraints. McMillen Jacobs coordinated with the hatchery to contract a local surveyor to provide an existing conditions survey and topography.
Initially McMillen Jacobs evaluated the existing infrastructure and collected sufficient background information to evaluate the hydraulic capacity of the existing system. With this information, alternatives were developed for different layouts and pipe routings for FFS to review and select a preferred alternative. Upon selection of the preferred alternative, McMillen Jacobs advanced the design to the 60% and 90% milestones for FFS review. The design included structural design of support structures and a head tank for degassing columns, hydraulic evaluation of the existing and proposed systems to insure proper flow and velocities were maintained for operation of the tanks, site civil grading, a small pump station for emergency backup supply to the sturgeon portion of the facility, engineer’s estimate of construction, and constructability analysis.