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7.3.E. - Page 16 ATTACHMENT 2 <br /> M. SEISMIC DESIGN FOR WATER PIPELINES. (Entire New <br /> Paragraph Added). <br /> 1. Special attentions and seismic design requirements shall be <br /> applied in areas of largest potential permanent ground <br /> movements (including settlements and lateral spreads) due <br /> to seismic-induced liquefaction or cyclic softening of soft <br /> clays. These areas are located within 200 feet of creeks, <br /> sloughs, culverts and San Francisco Bay (high water level), <br /> underlain by the Young Bay Mud or Liquefiable deposits. <br /> They are shown on the map in Attachment T as Area 1. <br /> 2. Special attentions and seismic design requirements shall <br /> also be applied to hilly service areas west of Alameda De <br /> Las Pulgas where there are high probabilities of earthquake- <br /> induced landslides. They are shown on the map in <br /> Attachment T as Area 2. <br /> 3. Special attentions and seismic design requirements shall be <br /> optional and required on a case-by-case basis for the <br /> remainder of the city service areas east of Alameda De Las <br /> Pulgas and west of US 101 mentioned in Paragraph 1 and 2 <br /> above. They are shown on the map in Attachment T as Area <br /> 3. <br /> 4. Pipelines require seismic designs shall be designed for <br /> seismic hazards in accordance to latest and applicable <br /> AWWA standards and the 2005 American Lifelines Alliance's <br /> Seismic Guidelines for Water Pipelines (ALA 2005) with <br /> reference to the City's Seismic Vulnerability Assessment <br /> Report (G&E September 2011 — Chapter 3). ALA (2005) <br /> provides guidance for selection of pipeline importance <br /> factors, return periods for earthquakes, methods to estimate <br /> soil permanent ground deformations, allowing pipe stresses <br /> and strains. These may be refined by cognizant geologists, <br /> geotechnical, civil, structural engineers and professionals, as <br /> approved by the City. <br /> 5. Minimum seismic design requirements are: <br /> a. The design of new pipes in the mapped area requires <br /> that the pipe should be reliable to withstand the <br /> seismically-induced permanent soil movements. <br /> Lacking site-specific calculation, the pipe should be <br /> able to sustain a 1% change in pipe length. This can <br />