1. The project would not affect any designated scenic street or highway (City of Petaluma, 1997). However, the City has indicated that it regards the visual character of Corona Road to be important in its development plan. There are public vistas from Corona Road and Highway 101 (ESA, 1997). Vehicles travelling easterly on the overpass at Highway 101 would have middle ground views of the site with a background vista of the distant hills. Parts of the substation, including two tall poles, and the connector power lines would be visible from the overpass. The proposed landscaping (when matured) would substantially reduce the visual contrast created by these facilities. Additionally, the proposed landscaping would substantially improve the existing visual quality of Corona Road for travelers in both directions. Travelers on Highway 101 would catch fleeting glimpses of some substation facilities at a distance, primarily the tops of the tall poles at the southerly end of the substation. Intervening vegetation along the east side of Highway 101 and other existing development largely obscures views of the site. Therefore, a less than significant impact to scenic vistas or scenic highways would occur.

  2. Pursuant to CEQA, public views are eligible for protection and/or mitigation from project effects that could have a demonstrable negative aesthetic impact. The proposed substation structure and equipment would have an ultimate height of approximately 45 feet. An eight-foot-high chain link fence and facilities for lighting would be installed around the substation. Steel poles, 65- and 85-feet high, would be erected as part of the project. The PEA provides photo rendering of existing conditions and graphical simulations of the proposed substation improvements from public areas surrounding the project site (PG&E, 1997).
  3. The City of Petaluma General Plan considers views of the Sonoma Mountains as important visual resources. As identified in the PEA, the principal views of the Sonoma Mountains would not be obstructed by project implementation. However, two poles at the south end of the substation would be visible. In addition, power line poles and a short length of conductors at the north side of Corona Road would be visible from the road and would interrupt existing views of the skyline. While this would not eliminate or block views of the Sonoma Mountains, in the context of the City policies from the General Plan, this impact would be potentially significant. PG&E has prepared a landscaping plan as part of its amended application for the Corona Substation (PG&E, 1998b). The landscaping plan includes plantings of trees, shrubs and understory vegetation to ameliorate the visual impacts of the project facilities along Corona Road. While the landscaping, when matured, would screen and soften the visual contrast of the facilities with the surrounding area, facilities would be partly visible. While the visibility of the power lines is unavoidable, the substantial reduction in visual contrast created by the landscaping would reduce the impact significantly. In addition, the proposed landscaping would result in a substantial visual improvement over the existing condition of the landscape in that area. The potential undergrounding of the existing overhead power lines on Corona Road and the implementation of the proposed Landscape Plan would enhance the overall visual quality of the project area.

    The City requested that PG&E consider undergrounding the connector power line as a visual mitigation. PG&E has rejected that design because of cost and because undergrounding would require some substantial facilities that would also induce strong visual contrast in the landscape along Corona Road.

    Because the substation site itself is set back from Corona Road, the proposed landscaping would substantially screen the transformer banks and other facilities from travelers on Corona Road. For travelers heading eastbound on Corona, the view of the proposed substation would be barely and briefly noticeable, if visible at all, because of the proposed landscaping and the recreational vehicle storage and existing Youngstown’s property fencing fronting on Corona Road (PG&E, 1998). For travelers heading westbound on Corona Road, views of the new conductors and substation would be brief, mostly limited to the portion of the view open through the entrance road to the substation. The vegetation and a chain link fence with redwood slats would screen the lower substation equipment along the remainder of this road segment. Visual impacts are thus considered less than significant.

    Residences along Pamela Court and Michael Drive (on the south side of the Service Center) have views toward the substation site where the PG&E building and existing redwood trees do not block these views. The PG&E building blocks most of the view to the proposed substation for residences located on the west side of the Service Center, while a four-foot-tall wooden fence partially blocks views to the substation site. PG&E proposes to construct a new wood fence six feet high along the western and southern perimter of the Serivce Center. The fence would not be tall enough to completely screen the upper parts of the substation and tall power poles. Visual quality impacts to residences located in the Youngstown Mobile Home Park are considered adverse as they would have partial close-range views of the facilities. With the implementation of PG&E’s proposed Landscape Plan, visual impacts would be reduced to a less-than-significant level.

    As described in the PEA, the following mitigation measures included as part of the project would reduce potential visual impacts to a less-than-significant level (PG&E, 1998):

Landscaping is proposed on the north and south sides of Corona Road, on the east and west side of the Service Center, and immediately surrounding the proposed substation. It would take approximately seven to ten years for proposed landscaping to completely filter views of the substation and yard, and to provide screening and shading of the parking areas.

Three single family homes are located to the east of the proposed substation. Because these houses are not oriented toward the substation, and proposed trees along the Service Center perimeter would screen much of the view of the facilities, the visual impacts on these residences are considered to be less than significant.

Views from Highway 101 would be either screened or brief in duration from vehicles. Existing vegetation, homes, and the Corona Road overpass block views from northbound traffic. The view of two poles on Corona Road from southbound traffic is subordinate to other landscape features in that area (PG&E, 1997). Visual impacts on highway traffic are considered less than significant.

Visual effects on North McDowell Boulevard include the installation of a new steel pole on the corner of North McDowell Boulevard and Corona Road and the replacement of the eucalyptus trees with smaller trees alongside the south side of the Fire Station. The new pole would increase in height from 65 to 85 feet, and the existing wood pole with distribution lines and other utilities would be reduced in height. The other poles along Corona Road, from the vantage point of North McDowell Boulevard, would be lowered in height or undergrounded (PG&E, 1997). Implementation of the Landscape Plan and possible undergrounding of utilities, pending agreement by other utilities using the poles, would ensure that the visual quality impacts on North McDowell Boulevard are less than significant.

In sum, with PG&E’s proposed landscaping plan, the visual impacts of the project are less than significant. Additional mitigation is not required.

  1. Existing lighting at the Service Center includes three manually operated exterior lights on the garage building. In addition, pole-mounted lights, which are on all night, are located at five locations within the Service Station yard. In response to residents of the mobile home concerns about existing Service Center conditions, including lighting, PG&E recently implemented a number of measures to mitigate nuisance lighting. One of these measures involved replacing the existing 400 watt exterior bulbs with 70 watt bulbs. Shields were also installed to direct the exterior lighting away from the neighbors’ line of sight (PG&E, 1998).

Lighting requirements for the proposed substation are likely to be reduced because of its location within an already secured and lighted Service Center. Lighting may be limited to manually-operated, downward-directed lighting at the northerly and southerly doors of each of the two metal clad switchgear (these switchgears are located closest to the western substation fence). These lights would only be turned on in the event that substation maintenance is required during nighttime hours. Lights on this equipment would be directed downward and would be shielded from the sight of residents in the mobile home park by the existing service center office building and by existing and proposed trees (PG&E, 1998). The proposed lighting plan would be designed to meet City lighting standards. This project would therefore have a less-than-significant impact related to the creation of light or glare on surrounding uses.

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