Garnett Valley Wastewater System | Las Vegas, Nevada

Granite Construction Delivers Water Treatment Capacity with EFCO Formwork

Las Vegas, Nevada

Expanding Treatment Capacity for a Growing Community

The Garnett Valley Wastewater System represents a vital infrastructure expansion supporting Phoenix’s rapidly growing population. This multi-phase project enhances wastewater treatment capacity by constructing six wet wells and three diversion structures across three separate sites, each located approximately one to two miles apart within the service area.

Together, these facilities form an integrated network that safeguards public health and environmental quality while supporting sustainable growth. The wet wells collect and manage wastewater flow, while the diversion structures act as mixing chambers that redirect and balance water pressure.

Each diversion structure included multiple in-wall pipe penetrations, ranging from 12 inches to 42 inches (300 mm to 1065 mm) in diameter, to provide interconnections between treatment zones.

Granite Construction’s Collaboration with EFCO

Faced with an ambitious dual-phase schedule, Granite Construction needed a forming solution capable of handling 25-foot-tall (7.6 m) walls, high pour pressure, and strict waterproofing standards. EFCO’s PLATE GIRDER® system was chosen for its strength, versatility, and reduced tie requirements.

To complete the system, EFCO supplied E-Z DECK® aluminum shoring for the deck lids, providing a complete forming and shoring solution from foundation to finish.

Formwork Performance for High Walls and Waterproofing

The project’s wet wells measured approximately 35’×13′ (10.7 m × 4.0 m) with 25′-high (7.6 m) walls, while diversion structures spanned 23’×25′ (7.0 m × 7.6 m) with heights up to 35′ (10.7 m) for double-lift pours.

Traditional forming methods using wood would have required hundreds of additional tie penetrations, each of which could have been a potential leak point. EFCO’s high-strength PLATE GIRDER® distributes concrete pressure through the frame rather than relying on tie spacing, reducing tie frequency and waterproofing work.

Custom Engineering for Complex Pipe Penetrations

EFCO’s engineering team developed project-specific forming layouts to accommodate every pipe sleeve and penetration, ensuring dimensional accuracy and waterproof integrity. These adjustments eliminated post-pour coring and rework, allowing all pipe interfaces to be cast in place and sealed within a single lift pour sequence.

Managing Construction Across Multiple Sites

To meet the aggressive timeline, Granite executed six structures simultaneously across three locations, cycling equipment as each pour completed. EFCO supplied enough PLATE GIRDER® and E-Z DECK® to maintain continuous forming operations.

Each deck incorporated heavy-duty pipe braces rated to resist wind pressures, and crews also employed wall aligners up to 16 feet (4.9 m) in length for precise vertical control during each pour.

EFCO field service representatives supported the Las Vegas-area sites throughout construction, helping crews quickly reconfigure equipment between lifts to ensure schedule adherence and consistent Quality.

Garnett Valley Wastewater System in Las Vegas, Nevada, supported with EFCO's <em>PLATE GIRDER®</em> and E-Z DECK®

Why Granite Construction Chose EFCO

This project demanded more than standard formwork—it required a technical partner. EFCO’s engineering expertise, pressure-rated systems, and field service support enabled Granite to maintain schedule, safety, and waterproofing standards simultaneously.

By combining PLATE GIRDER® wall systems and E-Z DECK® shoring, EFCO delivered a fully integrated forming solution that:

Handled 25′ tall (7.6 m) walls with an allowable pour pressure of 1,000 psf (48 kPa).
Reduced tie penetrations that compromise waterproofing.
Enabled multi-site forming operations under compressed timelines.

This project exemplifies EFCO’s commitment to the Lowest in-Place Concrete Cost (LIPCC)—through design Innovation that reduced rework, engineering precision that ensured performance, and service that kept contractors productive.

For complex infrastructure projects where structural scale, waterproofing, and schedule converge, EFCO delivers the partnership and performance that turn challenges into success stories.