The Santan Vista Water Treatment Plant (SVWTP) is jointly owned by the Town of Gilbert and City of Chandler, and treats raw water from the Colorado River via a 14-mile pipeline from the CAP (Central Arizona Project) canal east of Schnepf Road in Pinal County. Installation of the 14-mile, 48” ductile iron pipeline in 2009 included a cathodic protection system with test stations at 86 locations along the alignment to protect the pipeline from corrosion, and this system is reaching the end of its useful life. This project will evaluate the need and extent of a replacement cathodic protection system to meet current guidelines.

The SVWTP is located in Gilbert on Ocotillo Road west of Recker Road. The raw water pipeline is located in Ocotillo Road from the SVWTP heading east to Hawes Road, north in Hawes Road to just south of Rittenhouse Road, and then east along the Queen Creek Road/Pima Road alignment to the CAP Canal (see map below).

As part of the project, testing efforts are scheduled to take place beginning in September 2023 through February 2024. These efforts consist of multiple site visits, each gathering successively more detailed data related to the existing pipeline and cathodic protection system. Testing efforts will take place in the existing public right-of-way or pipeline easement.

Testing Efforts:

•  Soil, electrical current, and electromagnetic tests – along the pipeline alignment. The majority of this testing is non-invasive and simply requires walking the alignment and accessing the existing test stations, as well as non-paved/concrete surfaces adjacent to the pipeline utilizing small hand-held equipment and small gauge wire.
• Wenner 4-pin tests – at various locations to be determined based on the previous test results. Crew members will place four, equally spaced, ¾” diameter stakes or spikes into the ground. Each test takes less than an hour to conduct, and upon completion, pins will be removed, and the site restored.
• Soil borings – at various locations to be determined based on previous test results. Crew members will drill a 6”-8” diameter bore into the ground using an auger to extract soil samples. Several tests can be completed in a day and, upon completion, the bore hole will be backfilled and the site restored.

Questions? Contact us by email or call our project hotline at 480-898-4090.