AGENDA ITEM C8. COST/FUNDING SOURCE: $215,348.48/Uniform Rate (Total project costs $520, includes $304,952 previously committed to Phase II)

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1 AGENDA ITEM C8 DATE: February 6, 2017 TO: Matt Jordan, General Manager FROM: Charles H. Carden, Chief Operating Officer SUBJECT: South Pasco Transmission Main Phase III Condition Assessment Services with Pure Technologies U.S. Inc. - Approve. SUMMARY: Tampa Bay Water has been performing inspections of its Pre-Stressed Concrete Cylinder (PCCP) pipe to identify potential future issues. This allows staff to target pipe sections for repair or replacement rather than a more expensive replacement of the entire pipeline. Three pipeline sections have been inspected to date. Staff has negotiated an amendment with Pure Technologies U.S. Inc. to complete Phase III condition assessment activities at the South Pasco Transmission Main. RECOMMENDATION: Approve condition assessment services for the South Pasco Transmission Main Phase III with Pure Technologies U.S. Inc. COST/FUNDING SOURCE: $215,348.48/Uniform Rate (Total project costs $520, includes $304,952 previously committed to Phase II) DISCUSSION: A desktop analysis of the pipelines in Tampa Bay Water s Pre-Stressed Concrete Cylinder (PCCP) system was completed by AECOM to prioritize pipelines for inspection based on relative condition and consequence of failure. Three pipelines have been inspected so far: 8.6 miles of South-Central Hillsborough Regional Wellfield Transmission Main April miles of Cypress Creek Wellfield Collection Main condition July miles of the South Pasco Transmission Main (Phase I- northern portion) May The South Pasco Transmission Main provides regional supply to Hillsborough County s Fawn Ridge and Lake Park Treatment Plants, and to St. Petersburg s Cosme Treatment Plant. This Pre-stressed Concrete Cylinder Pipe (PCCP), constructed between 1961 and 1971, has been given a medium priority in the Tampa Bay Water PCCP Condition Assessment Program, based on potential condition and risk of failure. The condition assessment activities for this pipeline has been broken into phases to be completed over three fiscal years. Phase I of the northern portion of the transmission main was completed in May 2015.

2 Matt Jordan February 6, 2017 Page 2 Phase II condition assessment activities for the central portion of the South Pasco Transmission Main was scheduled to take place in fiscal year After Board approval in April 2016, a task was issued to Pure Technologies for $304, to inspect 2.16 miles of pipe. While preparing for this inspection, an 18-inch plug valve obstruction was identified on the record drawings near the intersection of Dale Mabry Highway and Van Dyke Road. Staff investigated replacing the plug valve, but cost was determined to be excessive. Staff have elected to defer Phase II, and to continue with Phase III of the southern and western portion of the South Pasco Transmission Main Assessment using the funds approved for Phase II to fund part of Phase III. An amendment to the Phase II amount for additional funds is required because Phase III includes more miles of pipe than were in the Phase II scope. Phase III includes approximately 6.22 miles of 42-inch diameter transmission main, and the assessment will cost a total of $520, including the previously approved Phase II funds and this proposed amendment. Other contract costs to open and close the line, provide entry for personnel and equipment and clear the line when completed, are budgeted separately and largely dependent on groundwater levels when the work is executed. There is currently only one vendor, Pure Technologies U.S. Inc. that provides condition assessment services for PCCP while keeping the line in service. Tampa Bay Water is using the terms, conditions and unit rates of the $35 million dollar Miami-Dade Contract BW9537-0/16 for pipeline condition assessment. This is the procedure used for other Tampa Bay Water pipeline condition assessments. The Miami contract was awarded February 15, 2012 and expires February 28, Miami-Dade has submitted a Supplemental Agreement to extend the existing contract for a period of six (6) months, commencing March 1, 2017 and expiring August 28, 2017, for approval this February The attached Agreement includes a copy of the Miami-Dade Contract, and a scope for the proposed Phase III assessment. The results of the condition assessment may lead to repair of areas determined to be in poor condition. Recommended repairs will be included in a future renewal and replacement project for portions of the South Pasco Transmission Main. BACKGROUND: Buried pipelines comprise approximately 80% of Tampa Bay Water s total agency assets. These pipes vary in age and material. Tampa Bay Water and many other Municipalities have had failures of pre-stressed concrete cylinder pipe (PCCP), which is constructed with a steel cylinder wrapped with pre-stressed wires, which is coated and lined with cement. Failure of PCCP can occur due to corrosion of the pre-stressed wires, caused by low-grade materials of construction, or damage during original transport and installation. For example, the 20-mile-long Cypress Creek Transmission Main was replaced in its entirety due to multiple pipeline failures and its critical position in the Tampa Bay Water system. It would be extremely costly to replace all the remaining 62 miles of PCCP in our system. Advanced condition assessment technologies have been developed over

3 Matt Jordan February 6, 2017 Page 3 the years to help utilities identify where pipe future failures are more likely to occur. This allows staff to target pipe sections for repair or replacement rather than a more expensive replacement of the entire pipeline. Attachment

4 PCCP Assessment South Pasco to Cosme WTP Transmission Main Suzannah Folsom, P.E. January 19, 2017 Tampa Bay Water 2575 Enterprise Road Clearwater, FL Dear Ms. Folsom: Pure Technologies U.S. Inc. (Pure) has been tasked with performing a condition assessment of 2.16 miles of piping including the southern portion of the Contract C-35 piping, the eastern portion of the C-18 piping and the northern portion of the C-21 piping. A plug valve obstruction at the north end of the C-21 piping has made inspection of this portion of the piping not feasible. This amended scope of services provides a revised scope for the next and final phase of the South Pasco Transmission Main condition assessment. We are pleased to offer our services to Tampa Bay Water (TBW) for pipeline assessment. We understand that TBW would like to assess the condition of the 42-inch diameter portions of Contracts C-35, C-18, C17, C-27 and C-28 that are part of the South Pasco Transmission Main. The pipeline is constructed of prestressed concrete cylinder pipe (PCCP), was installed in stages between 1961 and 1971 and extends from the South Pasco Transmission Main to the Cosme Water Treatment Plant in Odessa, Florida. According to the plans provided by TBW, the pipeline to be assessed consists of the following diameters and lengths: Contract C-35 o 42-inch Station to Station , 2,790 feet, 0.53 miles Contracts C-18 and C17 o 42-inch Station to Station 0+00, 25,557 feet, 4.84 miles Contracts C-27 and C-28 to Cosme WTP o 42-inch Station to Station 29+60, 4,509 feet, 0.85 miles The total distances listed above are according to a preliminary review of the pipeline asbuilt plans. Accessibility to the pipeline will be confirmed following a field visit and the total distance of assessment will be confirmed after the analysis of the collected data. The pipeline will be inspected in one mobilization and is tentatively scheduled to occur after April 1, A detailed project plan will be provided to TBW upon acceptance of this scope of work. In the interim, the preliminary plan for South Pasco will be to insert the equipment 1 P a g e

5 PCCP Assessment South Pasco to Cosme WTP Transmission Main through the access manhole at Station in Contract C-35 (the Horse Farm) and to extract before the Cosme Water Treatment Plant at Station in Contracts C-27 and C-28. Details for the insertion and extraction shall be coordinated with TBW, but if feasible, should include a temporary shut down and depressurization by TBW. This project will deliver to TBW the following: 1. The number of broken prestressing wire wraps in each inspected pipe section as well as any leaks found. 2. A performance curve for each pipe design class/soil depth combination for each pipe design with broken pre-stressing wires calculated using a 3-D non-linear finite element analysis 3. A structural engineering analysis detailing the repair priority for each pipe section with broken prestressing wire wraps. This report will provide TBW: A. Categorization of the structural damage found, allowing TBW to prioritize its rehabilitation program and allocate funds accordingly in an emergency and/or an annual basis. B. Information needed to extend the useful life of their pipelines using the information as a starting point for a root cause analysis if the pipeline is deteriorating. Cost Estimate Pure will deliver the electromagnetic inspection on the PipeDiver platform; leak detection will be performed on the SmartBall platform. TBW will be contracting Pure through an agreement Pure currently has with the Miami-Dade Water and Sewer Department (WASD). The terms and conditions associated with the assessment for TBW are based on the contract approved for WASD by the Miami-Dade County Department of Procurement Management (Master Agreement BW ). The cost for this project is referenced in Appendix B of this Master Agreement and is detailed in the table on the following page. 2 P a g e

6 PCCP Assessment South Pasco to Cosme WTP Transmission Main Service Quantity Unit Cost Total Cost PipeDiver/SmartBall Mobilization & Planning 1 $85, $85, Inspection/Analysis/Reporting: 6.22 miles* $69, $435, Total $520, Available Funds PO# $304, Additional Funds Requested $215, *- Mileage to be confirmed after data collection. TBW and Pure s responsibilities are detailed in the Master Agreement, Appendix A. We look forward to providing these specialized services. If you have any questions or concerns, please do not hesitate to contact me. Regards, Alan Bair alan.bair@puretechltd.com 3 P a g e