Laserfiche WebLink
<br />P' <br /> <br />..... <br />... <br />to <br />.... <br /> <br />SOUTHERN NEVNJA WATER AlfI'HORITY - TREATMENT AND TRANSMISSION FACILITY <br /> <br />c' <br />~ <br /> <br />Alternative HD-2: <br /> <br />Hoover Dam Intake to River Mountains WTF Site <br /> <br />Alternative HD-2 would consist of a new intake at Hoover Dam, an underground intake <br />pumping station, a WTF at the River Mountains site, water transmission pipelines, a new River <br />Mountains tunnel, two power substations, and overhead and underground power transmission <br />lines. The intake structure would tap into two penstocks downstream of Hoover Dam, within <br />the rock on the west wall of Black Canyon, An intake pumping station, located south of <br />Hoover Dam and Highway 95, would be constructed in an underground chamber. The intake <br />pumping station would lift water through new transmission tunnels and pipelines to the eastern <br />River Mountains and through a new River Mountains tunnel to the River Mountains WTF. <br />Power for the intake at Hoover Dam would be provided by a new 138 kV power line tunnel <br />from the existing Arizona-Nevada Switchyard. The remaining power supply would be the same <br />as described for Alternative SI-1 B. The substation and power lines along the eastern side of <br />the River Mountains would still be needed to provide power for the SNWS, which is being <br />upgraded under previous environmental documentation. <br /> <br />Alternative HD-8: Hoover Dam Intake to Railroad Pass WTF Site <br /> <br />Alternative HD-8 would consist of a new intake at Hoover Dam, an underground intake <br />pumping station, a WTF at the Railroad Pass site, water transmission pipelines, a new River <br />Mountains tunnel, two power substations, and overhead and underground power transmission <br />lines, The intake and intake pumping station would be the same as for Alternative HD-2. The <br />transmission pipelines would follow a similar route as for Alternative HD-2. A new River <br />Mountains tunnel would connect with the Railroad Pass WTF. Power supply for this <br />alternative would be the same as described for Alternative HD-2. An additional 69 kV power <br />line from the substation on the western side of the River Mountains to the Railroad Pass WTF <br />site would be needed. <br /> <br />THE IN-VALLEY TRANSMISSION SYSTEM <br /> <br />An In-Valley transmission system would be needed to convey water from the WTF to various <br />delivery locations specified by purveyors within the Valley. The In-Valley system would be the <br />same for all project alternatives. This water transmission system would connect with the <br />existing SNWS water transmission system at strategic locations, and deliver water to several <br />new aboveground and underground storage reservoirs in the Valley. The new water <br />transmission system, consisting of transmission pipelines, pumping stations, and reservoirs, <br />would be designed to best serve Valley water demands. Power supply for In-Valley facilities <br />would be provided by connections to existing and planned power infrastructure. <br /> <br />THE NO ACTION ALTERNATIVE <br /> <br />In addition to evaluating the construction of proposed SNWA-TTF facilities, the EIS also <br />evaluates an alternative to D.!l1 build the TTF system, to take "no action" with regard to <br />construction of the Proposed Project. <br /> <br />The No Action Alternative represents the most reasonable and foreseeable future conditions <br />and responses that are likely to occur as a result of denial of the Federal Actions and the <br />Proposed Project not being implemented. These future conditions include actions that may <br />have been addressed but were not analyzed in previous environmental documentation, yet are <br /> <br />SUMMARY <br /> <br />S-9 <br />