Northwest Water and Wastewater Master Plan Package 3A
- Fast preconstruction and construction time frame.
- Project averaged 20,000 worker-hours and $6 million in billings per month.
- Installation of two 110-inch tunnels (810 lf each) under a live freeway.
This project for the City of Phoenix required installation of utilities within an accelerated schedule that allowed less than six months for preconstruction and procurement and a nine-month window for construction. The scope included over 12 miles of pipe installation, structures, valves, appurtenances, maintenance road grading, and restoration of the existing roadway. New construction utilities included over 26,000-LF of a 36-inch water main; 25,700-LF of dual 24-inch HDPE sewer force mains systems; 11,000-LF of gravity RGRCP and VCP sewer lines (54-inch to 36-inch) and numerous concrete structures site-wide with highly specialized coatings. To safeguard against supply chain issues, these pipe materials were procured at the 90% plan phase with an early procurement GMP.
Tunneling under the I-17 Freeway and maintaining the schedule was a challenge due to hard dig soil conditions as well as the mobilization of specialized equipment, permits and site preparation. To meet this challenge, Sundt proposed and priced eight different tunneling scenarios. This included various types of tunneling methods, four different tunnel sizes, and several variations related to length, alignment, and crossing point. In working with the design team, we proposed performing a Rib and Lag Tunneling method for two 110-inch tunnels. This option provided the optimal separation distance between sewer and potable water, while also allowing for future carrier pipes to utilize these same bores.
This project epitomized excellence in partnering through the synergy of all parties involved from the owner, designers, neighboring contractors and the end utility user. It was critical to the growth of the community, providing significant economic development opportunities to the neighboring municipalities and the state in its entirety.
Awards & Accolades
Northwest Valley Infrastructure
APWA Project of the Year Award Above $75 Million
AGC Build Arizona Award