Figure 3.3-1. WAPA Transmission Line Re-routing Alternatives Overview

Figure 3.3-1. WAPA Transmission Line Re-routing Alternatives Overview

Based on current designs of the WAPA transmission line re-route alternatives, which designs are subject to change prior to construction, the Western Route, when compared to the Eastern Route, would result in an additional five steel monopole tower structures; 116,308 pounds of custom steel; 48 cubic yards of concrete volume; 22,129 pounds of steel rebar; 26,795 feet of conductor; 9,191 feet of optical ground wire (OPGW); and 294 feet of steel-shield wire. The additional materials, weights, distances, construction activities, and required access roads would result in additional environmental and resource impacts when compared to the Eastern Route. The Eastern Route is the preferred route because it is more accessible, is located on more suitable topography, has lower estimates in the aforementioned measures, and, therefore, would be easier to construct and maintain over the Project lifecycle.

The largest constraint for the Eastern Route is the proximity to the WSA bounding the feasible alignment to the east and the proposed upper reservoir wall bounding the feasible alignment to the west. During preliminary design, the closest approach to the WSA was approximately 34 feet from the centerline of the re-routed transmission, with no direct overhang of cables into the WSA. The closest approach to the upper reservoir wall base is approximately 37 feet from the centerline of the transmission re-route. This constraint is navigable and all code-required clearances are feasible.