2014 – Dibble Engineering – Subregional Operating Group Southern Avenue Interceptor

The Southern Avenue Interceptor (SAI), a multi-owner regional interceptor governed by the Subregional Operating Group (SROG) cities of Glendale, Mesa, Phoenix, Scottsdale, and Tempe, is infrastructure managed by the City of Phoenix Water Services Department (Phoenix Water). The SAI is approximately 98,500 linear feet and ranges in pipe diameters from 48-inches to 90-inches and is approximately 19 miles in length, extending from 48th Street and Southern Avenue to the 91st Avenue Wastewater Treatment Plant (WWTP), which treats approximately 150 million gallons of effluent per day.

In 2013, SROG’s condition assessment of the SAI sanitary sewer pipe identified six segments of pipe requiring rehabilitation. YPMO was a sub-consultant to Dibble during the 2014 design phase to provide public information and outreach prior to construction. Anne Thompson prepared a PIO Plan and developed a pre-construction project notice to conduct business outreach along the entire alignment to discuss the upcoming manhole and pipe rehabilitation work with hundreds of businesses, schools, and housing complexes along Southern Avenue. Coordination was needed along the six pipe rehabilitation areas located in front of hundreds of businesses, including a school bus barn, a cemetery, and several housing communities with limited access. YPMO created a project website to share construction updates during the 2-year duration of work.

Construction for those segments, and for 139 manholes spread throughout the interceptor, was completed between 2015 and 2017. The SAI is constructed of PVC-lined reinforced concrete pipe and required a sewer bypass for each section to install a structural liner. The bypass was constructed and set up 24/7 for several months at each location.

In 2017, YPMO provided PIO services to CONSOR Engineers who were awarded the construction phase CA&I services. The outreach for the final pipe rehabilitation segment included close coordination with the City of Tempe and businesses at the intersection of 48th Street and Southern Avenue. This intersection had historically been the site for a variety of utility construction projects and the business owners were concerned about access issues. The traffic control around the bypass pipe ran down the center of the street was complex, but there were very few access issues or complaints.

With 15 years’ experience working with the Phoenix Water, their project managers, and its consultants and contractors on re-occurring programs like this one, YPMO is a trusted go-to PIO firm. Now, 10 years later in 2024, YPMO is once again providing PIO services to CONSOR for the current condition assessment of entire length SAI pipe, the 51st Avenue siphon, and approximately 154 associated manholes and structures on the interceptor.