Zone 3D/4A 42-inch Water Transmission Main

Improving reliable water delivery for Phoenix.

The City of Phoenix is implementing a series of major infrastructure improvements located in Pressure Zones 3D and 4A to move water from the Salt River Project (SRP) system northward to the Central Arizona Project (CAP) service area. These improvements will help to ensure reliable delivery of water to the northern parts of Phoenix during periods of drought and possible reduced availability of CAP water supplies. The improvements covered by this project consist of replacing approximately 2.5 miles of an existing 36-inch WTM with a new 42-inch WTM along 35th Avenue from Thunderbird Road to Grovers Avenue. The new WTM will provide increased capacity and eliminate the flow restrictions caused by the existing 36-inch WTM.

35th Avenue Excavation for Utility Location


City of Phoenix

Phoenix, AZ

$7.5 M

Project Lifecycle

Dibble designed a new 42-inch diameter WTM segment to increase the overall capacity of the water transmission main. Dibble also performed a corridor study to investigate and analyze potential corridors for the replacement segment, which resulted in the identification of the most advantageous route in conjunction with the CMAR

35th Avenue Survey
Team Preparing for Site Inspection
Vac Truck
Top of Casing