JWF has completed the Mechanical Dewatering Improvements and San Dieguito Dam Improvements project for the Santa Fe Irrigation District in Rancho Santa Fe, California.
The work was located on two sites: the R.E. Badger Water Filtration Plant and the San Dieguito Reservoir. The 100-year-old San Dieguito Dam and Reservoir serves as water storage for the Santa Fe Irrigation District and the San Dieguito Water District. The project included design and construction to remove and manage solids, an integral part of the water treatment process.
The R.E. Badger Filtration Plant is a conventional water treatment plant built in 1970, owned by both the San Dieguito Water District and the Santa Fe Irrigation District. While the plant can treat up to 40 million gallons a day and over 7 billion gallons of potable water a year, mechanical dewatering improvements increase operational efficiency and decrease process costs. This project expanded the solids mechanical dewatering system at the filtration plant with improvements including rehabilitation of the existing gravity thickener, modifications to the existing sludge wasting pump station, sludge holding tank, centrifuge feed pump station, centrifuge building, remodeling of the existing centrifuge building, relocation of the existing centrifuge, new centrifuge, new screw and belt conveyors, polymer feed systems, and utility water pump station.
Before this project, a great number of solids removed at the filtration facility have been discharged to the San Dieguito Reservoir. Constructed in 1918, the San Dieguito Reservoir has served residents in the area for over a century. The reservoir is used for storage of Lake Hodges water while also serving as emergency storage. Areas of rust and degradation that have occurred over time were repaired and upgraded in accordance with current standards and regulations. The project upgrades the existing outdated guardrails and walkways to meet current safety standards. Upon inspection it was determined the exterior face of the 1918 built San Dieguito Dam also needed refurbishment. The project provides concrete refurbishment, including repairs of concrete cracks and spalls, and blasting and recoating of the anchor steel plates to address surface wear.