The Metropolitan Water District of Southern California (Metropolitan) has hired leading environmental engineering and construction services firm Brown and Caldwell to design a sectional replacement of the Rialto Feeder, a critical Southern California water supply pipeline.

Metropolitan’s mission is to ensure a safe and reliable water supply for the 19 million people in Southern California in the face of climate change and extended drought.

The Rialto Pipeline, constructed in 1972, is approximately 30 miles long with a diameter ranging from 96 inches to 144 inches. It conveys untreated water from DWR’s (California Department of Water Resources) Lake Silverwood to Metropolitan’s Live Oak Reservoir in La Verne. Under normal conditions, the Rialto Pipeline relies on raw water deliveries from the East Branch of the SWP (California State Water Project) via DWR’s Devil Canyon Afterbay. Member agencies with service connections on the Rialto Pipeline include the Inland Empire Utilities Agency, Three Valleys Municipal Water District, and the Upper San Gabriel Valley Municipal Water District.

Located in Upland, the aging 35-foot section of the large-diameter pipeline requires replacement due to mortar lining degradation. As design engineer, Brown and Caldwell will provide professional services, encompassing utility investigations, design of a new cement mortar lined 121.5-inch diameter steel replacement pipe, restoration of existing improvements, and permit approval from the City of Upland.

Furthermore, the firm will work closely with Metropolitan to develop a construction sequencing plan to minimize service disruptions during replacement work. Once design is complete, the new section of pipeline is anticipated to be installed by late 2024.

“We applaud Metropolitan for their proactive approach to maximizing the life of existing infrastructure,” said Brown and Caldwell Vice President Steve Hirai. “Our team is honored to work with Metropolitan leadership to help maintain a vital water supply artery to residents and businesses of Southern California.”