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<br />6.2A
<br />Page 51
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<br />implemented. Under the No Project Alternative, if any part of the system were to fail in the
<br />future, such as during an earthquake, in spite of retrofits made to the system or before they could
<br />be made, the SFPUC would proceed with the necessary emergency repairs or replacements,
<br />which may be exempt from environmental review, per Section 15269 of the CEQA Guidelines.
<br />
<br />Under normal operating conditions (e.g., no emergency repairs), the No Project Alternative
<br />would avoid most of the short-term, construction-related impacts associated with the Project,
<br />including air quality impacts from construction and hauling activities, potential asbestos releases
<br />during tunnel construction, direct impacts on special-status species, loss of trees, excavation
<br />effects on buried cultural resources, exposure to underground hazardous materials, waterway
<br />crossings, construction noise, disruption of recreation, and temporary traffic disruptions. From
<br />among these, significant and unavoidable impacts of the Project were identified, most of which
<br />would be avoided or reduced in the short tenn by the No Project Alternative, including
<br />construction noise produced close to residences and other sensitive receptors and the loss of
<br />mature trees along the right of way
<br />
<br />However, the Commission rejects this alternative as.infeasible because it meets none of the
<br />SFPUC's Project objectives for the reasons discussed below:
<br />
<br />The SFPUC has determined, through engineering studies completed by G&E Engineering
<br />Systems and OPAC Consulting Engineers, that BDPL Nos. 1 and 2, the Bay Division system's
<br />two oldest pipelines, would require several repairs and seismic upgrades. In particular, these
<br />reports indicated that portions of the pipelines, bridge, and trestles that support the pipeline as it
<br />crosses San Francisco Bay at Newark Slough and the Dumbarton Crossing may be damaged
<br />following an earthquake. Keeping this segment ofBDPL Nos. 1 and 2 in service would require
<br />modifications to its supports.
<br />
<br />In addition, photographic investigations show that the interior pipeline walls in several areas of
<br />BDPL No. I have suffered advanced pitting, or narrowing of the walls, resulting in sttuctural
<br />degradation. Also, ground shaking could damage BDPL Nos. 1 and 2 in the area of Pulgas
<br />Tunnel Portal, where parts of the pipeline are aboveground and are supported by metal trusses.
<br />Several pipeline connections in this area would need to be modified with expansion joints.
<br />However, under this No Project alternative, no improvements to address these system issues
<br />would occur.
<br />
<br />Further, in spite of seismic retrofits, the existing pipelines would continue to age, thereby
<br />increasing the chances of pipeline failure. This alternative would also leave SFPUC water
<br />customers vulnerable to the impacts of a severe drought or a catastrophic interruption of an
<br />imported water supply. Pipeline failure could come in the fonn ofa pipe bursting or as a result
<br />ofa major seismic event. The u.S. Geological Survey has estimated a 62 percent probability of
<br />at least one magnitude 6.7 or greater earthquake between 2003 and 2032. The failure of one or
<br />more pipelines would result in the loss of potable water supply to both residential and
<br />commercial customers, resulting in major wa.te~s:h~~ge~~$."t.l~l:1 ~l.1()~a.g~"s.~<:)~lqr.~q\l"ir~ \,\I~~~~"""
<br />" "riitioriingirid the:iri1porlirig"ofwater until the" repairs "are completed; "
<br />
<br />This interruption of water supply would likely result in significant economic impacts from loss
<br />of business revenue and the cost of importing water. Economic impacts would also result from
<br />the cost of repairing damaged pipelines, associated facilities, and other structures (e.g., homes
<br />and businesses). If needed in sensitive areas such as wetlands, pipeline repairs could result in
<br />significant impacts on these resources and the wildlife that rely on such habitat.
<br />
<br />In addition, the No Project Alternative would not be consistent with SFPUC's mission of serving
<br />San Francisco and its Bay Area customers with reliable, high quality, and affordable water.
<br />Existing facilities were constructed as early as the 1920s and at the time were not sized to meet
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