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portions of the transmission system which remain unaltered in the past decade or so, we will re- <br />use the previous assessments. <br /> <br />Distribution System. <br /> <br />Tanks. We will assess the earthquake performance of each tank (selected for detailed evaluation) <br />for performance in probabilistic (about 100-year and 500-year return period); and planning level <br />scenario earthquakes (including South Whidbey Island M 7; Cascadia Subduction Zone M 9). <br />The probabilistic earthquakes will be based on code-type hazards and computations. The <br />scenario earthquakes are most important for evaluating the system as a whole in earthquakes. <br />Damage modes may include damage to attached pipes; damage / wrinkling to steel shells; water <br />sloshing-induced damage. <br /> <br />Pump station. We will perform structural check as to the performance of the pump station <br />building; as well as consider important equipment (pumps, motors, motor control centers, <br />emergency back-up power). <br /> <br />Distribution Pipe. We will compute the potential for pipe damage in various scenario earthquake. <br />Damage may include leaks or breaks in mains; damage to service laterals (up to the meter). We <br />will use distribution pipe fragility models based on ALA (2001), additional relevant empirical <br />pipe damage information in other earthquakes since then (notable Napa 2014; Christchurch <br />2011; Fortuna 2022; etc.), and, as suitable, reflect local soil resistivity. The results will be <br />tabulated by style of pipe (steel, concrete cylinder, cast iron, asbestos cement, ductile iron, PVC, <br />PE, etc.); and by pressure zone. Post-earthquake leak rates will be estimated. For scenario <br />earthquakes, we will estimate the number of fire ignitions. Allowing for emergency response <br />actions, we will tabulate how long water will be available for fire fighting; and how long it will <br />take to repair damage and to restore the system to pre-earthquake performance. <br /> <br />Reservoirs 1, 2, 3 and 6. These reservoirs include various types of liner systems (including <br />Hypalon bladders, etc.). Reservoir has since been removed from service. The seismic weaknesses <br />may include damage to liner systems (and hence increased leak rates); damage to roof systems; <br />damage to embankments; damage to inlet-outlet pipes. Depending on the style of construction <br />and past evaluations, there may be some uncertainty as to the earthquake performance of <br />embankments due to liquefaction / landslide; we will so note that, and recommend any additional <br />optional geotechnical evaluations that may be suitable. <br /> <br />Task 4. System Performance, Capital Improvements, Benefit Cost, Draft Report <br /> <br />We will use the findings from Task 1, 2, 3 and evaluate the system, as a whole, version target <br />Performance Goals. The prior Vulnerability Assessment (2012) provide target Goals, and these <br />may have been updated / revised by the City in the interim. The Goals will be set for "probable" <br />and "maximum" earthquake conditions as suitable. <br /> <br />We will assess the current system performance versus these Goals. We will develop 4 levels of <br />possible Capital Improvement Plans (CIPs) (seismic mitigation of facilities; pipe replacement;