AgdaPkt 2011-10-24 - Laserfiche WebLink

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X 7. B. - Page 9 Executive Summary BB61V0 BIIV 11,! RW N_ . The City has more than 260 miles of distribution pipeline, ten pump stations and 12 storage reservoirs that are used to distribute water to customers. Of the 260 miles of pipeline, 93 miles is cast iron (CI), 42 miles is asbestos concrete, 82 miles is polyvinyl chloride (PVC), and the remaining 43 miles is a variety of materials. The average age of pipeline in the system is 35 to 40 years old, with some pipeline over 100 years old. In general, the cast iron pipeline is the oldest in the system, the oldest pipeline dating back to the early 1900's and the PVC is the newest pipeline in the system. The large amount of PVC reflects the City's efforts over the last 15 to 20 years to proactively replace older pipeline. The City's pump stations and tanks are of older vintage, with an average age approaching 50 years old, but are well maintained. ES.5 ESTABLISHING THE MASTER PLANNING FRAMEWORK (CHAPTER 4) The first and most critical component to an effective Water System Master Plan is the development of a consistent evaluation framework. This framework provides perspective for the project's multiple, parallel tasks and aligns them with the project objectives, resulting in recommendations that are aligned and consistent with the City's LOS Goals. This framework is presented graphically in Figure ES -1 and described below: Step 1: The framework first confirmed the City's LOS goals, and then for each of the goals (effective and efficient service delivery, health and safety, cost effectiveness) developed metrics to define the level to which existing conditions and recommended solutions met these goals. Step 2: Each of the three assessments (system capacity and operational reliability, seismic vulnerability, pipeline and facility renewal /replacement) was completed by evaluating the City's water system needs as compared to this pre - established benchmark. Although the three assessments were conducted independently, this process provided consistency and a common focus across the independent evaluations, which involved a diverse set of issues and project criteria. Step 3: Within each assessment, project solutions were combined and formulated into programs based on their individual combined benefit in the context of addressing the established metrics. Step 4: Once the programs were identified for each assessment, a combined analysis was conducted for all programs to identify overlaps and conflicts, and to find synergies between these programs. Step 5: The consolidated programs were then assembled by priority into three potential implementation scenarios, and the programmatic costs for these scenarios determined. The implementation scenarios were then evaluated in a qualitative manner as to risk versus reward to develop a recommended scenario. WEST Y O S T ASSOCIATES ES -5 City of Redwood City September 2011 Water System Master Plan o\c\369\06-09-01 \wp\mp\05261 0_0ES