91st Avenue UPO5 Water Treatment Plant
Water & Wastewater — Phoenix, AZ

91st Ave UPO5 Water Treatment Plant

This regional wastewater treatment plant expansion is an end-of-line facility that receives flows from the Arizona cities of Phoenix, Glendale, Scottsdale, Mesa and Tempe. The 37.5 MGD expansion includes primary clarifiers, aeration basins, secondary clarifiers and an odor control facility.

The 91st Avenue Wastewater Treatment Plant is jointly owned by the Sub-Regional Operating Group (SROG) Cities of Glendale, Mesa, Phoenix, Scottsdale and Tempe. It is operated by the City of Phoenix.

UP05B is an expansion of a wastewater treatment facility with critical connections at its influent and effluent points to the existing 91st Avenue Wastewater Treatment Plant, which had to remain operable. Construction of a new wastewater treatment facility of this magnitude — the facility’s capacity is 25.5 mgd — is rare. Another unique aspect of the project, UP05B was the second phase in the construction for an ultimate 385 mgd capacity Unified Plant at the 91st Avenue Wastewater Treatment Plant.

The UP05B project represents the commitment of community leaders to promote, plan, design and construct the most efficient treatment facilities to help meet growing demands. It will support and sustain economic growth, the environment and public health and welfare. The UP05B project supports and improves growth and economic development by providing sustainable and flexible water treatment services for the SROG cities across the Valley. The project provided jobs for over 230 Valley residents. It also supported positive growth and economic impact to a number of Valley industries/companies that provided local building materials and specialty trades for construction.

McCarthy Incident Rate
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  • Malcolm Pirnie, The Water Division of ARCADIS

The level of coordination by McCarthy on UP05 allowed for a large amount of work to be completed with minimal impact upon operations of the facility. The advanced planning also afforded plant staff to continue with scheduled maintenance activities, as well as save money for our residents, a vital concern in these tough economic times.

Rick Shane, Construction Project Manager
City of Phoenix


Jaren Murphy

Jaren Murphy

6225 N 24th St
Ste 125
Phoenix, AZ 85050

Awards and Recognition

Arizona Water Association Logo
2011 Wastewater Project of the Year

Arizona Water Association
91st Avenue UP05 WWTP Expansion