Projects - Wastewater System Evaluations

Wastewater System Evaluations

The City of Treasure Island owns (either partially or in full) approximately 2.2 miles of wastewater master force main stretching from the Master Pump Station on 108th Ave. to St. Petersburg’s Pump Station No. 61. From here, the flows are routed to St. Petersburg’s Northwest plant for treatment. The City pays an out-of-jurisdiction surcharge in the amount of 25% to St. Petersburg for treatment. The force main was constructed in the 1970’s and has three subaqueous crossings along the Causeway. The easterly portion of the force main is shared with the City of St. Pete Beach. The last force main assessment was performed in 2010 and the overall condition was stated to be “relatively good”. The assessment recommended that the study be repeated in 8 to 10 years.

Master Force Main Assessment
Inspection of the City’s wastewater master force main is crucial to ensure proper maintenance and proactive replacement prior to failure. The scope of work for the assessment included general review of the wastewater system and the previous inspection data, numerous field inspections, ultrasonic testing, and bathymetric survey to result in compiled survey data and a report with a recommended maintenance schedule and an estimated year of replacement. This project was initiated in December 2020 and has been completed. It was determined that this portion of force main may have about 40 years of service life remaining. It is recommended that this evaluation be completed every 10 years to reevaluate the pipe's condition.

Wastewater Treatment Feasibility Analysis
The City’s Master Pump Station will require substantial rehabilitation or replacement within the next five years. Along with the aging master force main and the timing of the County’s Wastewater Master Plan, now is the ideal time to evaluate treatment alternatives. The study will determine the feasibility of routing wastewater flows to Pinellas County either alone or in conjunction with neighboring municipalities. Under this study, re-routing costs will be estimated, along with a projected return on investment time frame associated with the elimination of the current 25% surcharge from the City of St. Petersburg. If the City and County determine that the project is financially feasible, the technical feasibility of the selected alternatives will be evaluated by conducting route analyses for the pipe corridor. As a preliminary step in the project, Pinellas County Utilities is currently evaluating how the addition of the City's flows might affect their system's performance. This study is ongoing.

Updated: 2 Sept. 2021