Crews in southern Utah County are nearing completion of one of the largest water infrastructure projects in the western United States as they prepare to finish the final 4.3-mile segment of the Spanish Fork-Santaquin pipeline, the last major construction link in a multibillion-dollar project that will provide locals with a viable water supply for decades.
Led by the Central Utah Water Conservancy District (CUWCD) and general contractor VanCon, Inc., the Santaquin Reach is the culmination of a 17-year effort to transport water from the Colorado River across the Wasatch Mountains to high-growth communities in southern Utah County. Tapping into the massive storage of Strawberry Reservoir in the mountains, the Spanish Fork Santaquin Pipeline (SFSP) it provides enough water to protect 240,000 inhabitants from drought.
“The completion of the SFSP is a critical milestone in building the backbone that allows fast-growing communities in southern Utah County to begin receiving water allocations that have been requested for decades,” said Brad Perkins, project manager for the Central Utah Project. (CUP).
With the SFSP nearly complete, the Utah Lake System (ULS) now delivers water from Strawberry Reservoir in a continuous pipeline along a 35-mile stretch from Orem to Santaquin. In Orem, the ULS connects with other pipelines to deliver water as far north as Salt Lake City.
The Santaquin Reach is notable for large, 60-inch-diameter spiral-welded steel pipes designed to withstand the high pressures required for regional water distribution. Each pipe segment is 40 feet long and weighs 25,000 to 30,000 pounds. Its installation required more than 500 individual “picks” to complete the 4.3-mile span.
To protect the pipe during installation, VanCon used two large excavators and 6- to 8-inch-wide nylon webbing to ensure the concrete-on-tape liner remained intact.
The pipe was installed at an average depth of 11 to 15 feet, with some areas exceeding 20 feet. “Soil conditions ranged from silty sands, gravelly sands, to gravels,” says Chad Hunsaker, vice president of VanCon. He says crews installed more than 50,000 cubic meters of controlled low strength material (CLSM) around the pipeline to ensure 100% compaction and protect the pipeline.
“The pipe was installed using a sliding rail shoring system for all 25,000 linear feet,” says Hunsaker. “This type of shoring system is complex and requires a large crew to install and remove the shoring and provide a safe work area for the labor that installs, welds and fills the pipe.”
Precision welding and protection
While many large-scale water projects rely on joints, the SFSP uses bell-and-tenon joints with double lap welds. This meant 90,000 linear feet of welding, handled by a team that typically consisted of one welder inside the pipe and two outside.
The pipe contained cylinders of two different thicknesses: one-half inch and five-eighths inch. The half-inch cylinders required four passes in and out of each joint, and the five-eighths required five, says Hunsaker, noting that quality control was critical as each joint underwent visual inspection, air pressure testing and ultrasonic testing by QTI inspectors who remained on site full-time during installation.
To help protect the pipeline in Utah’s rugged and rocky terrain, the steel was prepared and wrapped with a dielectric tape system and multiple layers of polyethylene tape for corrosion prevention and mechanical protection. For added assurance, a 1-inch-thick layer of reinforced cement mortar is applied over the tape system.
“Once installed, the pipe receives additional protection with Controlled Low Strength Material (CLSM) trench backfill,” says Jacobs project manager Ryan Phillips, design engineer for the job. “Inside, the steel pipe barrel is centrifugally coated with a cement mortar coating.” Pipe joints are grouted after field welding for a continuous smooth finish lining. To provide cathodic protection, passive anodes were installed at regular intervals along the length of the pipeline.
The “Golden Spike” connection.
Laying miles of pipe was a challenge, but the most difficult moment was the physical “tie-in”—the point where the new 4.3-mile section finally joined the 45 miles of pipe already in the ground. The challenge was that both pipes were plugged and filled with millions of gallons of water. Before the crew could join them, they had to drain the system and cut through the thick steel plugs to expose the open pipe.
Because this required taking the water system offline, the team spent three months planning the exact timing just after the end of the 2025 irrigation season.
“Once the irrigation season was over, the existing pipe was drained and the new pipe was temporarily connected with a smaller pipe between the two to drain the new pipe into the existing pipe, so the nail heads. [the steel end-caps] could be removed,” says Hunsaker.
With the lines drained and the ends exposed, the team joined these two massive ends by using a “butt-strap” connecting ring — a two-foot-wide steel collar that overlaps both the existing and the new pipe. This ring was then welded both inside and out, creating four separate weld locations within a two-foot area to ensure the joint could withstand the massive pressure of the system. Phillips says that while the double-welded strap allows for some flexibility, the tolerance for the link was a few centimeters.
crossing the finish line
The project is currently in final commissioning, with crews completing the nine diversion vaults that were constructed along the entire SFSP span, and electrical and IT crews currently integrating isolation and plunger valves into the SCADA network. Perkins says all work is scheduled to be completed by June 30, with regular water deliveries beginning next spring.
