The Western Area Power Administration was established in 1977 as a part of the Department of Energy. Western’s primary mission is to market and reliably transmit power from the federal hydro projects. Western markets and transmits approximately 10,000 megawatts of power from 55 hydropower plants. Western also markets the United States’ 547 megawatt entitlement from the coal-fired Navajo Generating Station near Page, Arizona.
Western, as a wholesale power provider, delivers bulk wholesale power to local non-profit utilities. They in turn, provide retail service to consumers.
Western has four Regional Offices: Billings, Montana; Phoenix, Arizona; Loveland, Colorado; and Folsom, California. The Colorado River Storage Project Management Center is located in Salt Lake City, Utah. Western’s Sierra Nevada Region markets firm Federal Power to 76 preference customers in northern and central California; specifically to 17 municipalities, 1 rural electric cooperative, 8 state agencies, 17 federal agencies, 24 irrigation and water districts and 9 public utility districts.
Currently, Western markets approximately 1500 MW of firm power to its Sierra Nevada Region customers. Sources for this power include:
| The
electrical
power
system
consists
of
three
primary
elements:
generators,
transmission
systems,
and
distribution
systems.
Generators
convert
fuel
(such
as
coal,
natural
gas,
nuclear,
wind,
solar,
or
water-power)
into
electricity.
The
electrical
transmission
system
connects
generators
to
distribution
systems
using
high-voltage
power
lines.
Distribution
systems
serve
retail
customers.
The transmission system has evolved into a complex regional network interconnecting several states and allows generators to serve loads hundreds of miles away. To efficiently transmit large amounts of power across these distances the transmission lines operate at very high voltages, typically 230,000 to 500,000 volts (230 kV to 500 kV). The regional transmission system also allows sharing of power resources. For example, in the summer when air conditioning loads are high in California, surplus power can be imported from the Northwest. In the winter, surplus power can flow in the opposite direction to serve heating loads in colder climates. Also, the extensive interconnection of the electrical power systems helps utilities handle unexpected problems, such as the failure of a power plant, since other power plants in the system can make up for the loss of output. Operation of this complex system is a very delicate balance between the load on the system at any point in time and the generation needed to match that load. This balance is monitored by system frequency and voltage. Since the load is not exactly predictable, power plants continually adjust their output to keep the system balanced. If this balance is not maintained within the very close tolerances needed by all equipment connected to the electrical system, automatic devices "trip" (or shut-off) circuit breakers to de-energize those part of the system in jeopardy. |
|
Western
operates
and
maintains
an
extensive,
integrated
and
complex
high-voltage
federal
power
transmission
system
to
reliably
serve
the
electrical
load
of
various
types
of
customers
and
project
facilities.
This
responsibility
is
established
by
Federal
legislation.
Sierra
Nevada
Region
meets
this
mandate
by
operating
and
maintaining
Federal
facilities
throughout
Northern
California.
Western’s facilities are interconnected with those of other utilities. We must meet operating criteria and maintenance standards set by utility industry groups and we must maintain our ability to deliver power to our customers. Because of the severe pressures on the interconnected transmission system in the Sacramento area, Western must now consider alternatives to ensure it can meet its contractual responsibilities to deliver electrical power to its customers.
Western identified five broad alternative categories (new power generation, demand-side management (DSM), distributed generation, new transmission, and transmission upgrades) to consider in the Notice of Intent (65 FR 48496). During the subsequent four-phased alternative development process, the alternatives of new power generation, distributed generation, and DSM were eliminated from detailed review. New power generation and distributed generation alternatives would not solve short-term voltage support and reliability issues. DSM would be more applicable to the distribution of electricity, and the local utilities have implemented programs to decrease the electricity load during peak-use hours. Western believes that in the short term, imposing regulations of this type would not solve the reliability issues.
The Proposed Action would include: 1) reconductoring the existing single- and double-circuit, 230-kV transmission line from the Elverta Substation to the Tracy Substation; 2) constructing a new double-circuit, 230-kV transmission line paralleling the existing double-circuit, 230-kV line from the O’Banion Substation to the Elverta Substation; and 3) realigning portions of the existing Cottonwood–Roseville single-circuit, 230-kV transmission line north of Elverta Substation. A detailed description of the Proposed Action is presented below:
Western would reconductor 72.6 miles of single- and double-circuit, 230-kV transmission lines between Elverta Substation and Tracy Substation. Reconductoring would be completed in two phases to minimize service disruption. The first 11.2 miles would be a double-circuit, 230-kV transmission line between Elverta Substation and Hurley Substation. The second 61.4-miles between Hurley Substation and Tracy Substation would include a combination of either two single- or one double-circuit transmission line. From Hurley Substation to Hedge Substation, there would be one double-circuit, 230-kV transmission line. Hedge Substation to Tracy Substation would include a combination of either two single-circuit, 230-kV transmission lines, or one double-circuit, 230-kV transmission line. Western would improve the fiber-optic communication system where necessary, replacing one of the two existing shield wires with a fiber-optic cable.
Western would construct a new, 26.6-mile, double-circuit, 230-kV transmission line between O’Banion Substation and Elverta Substation. It would parallel the existing O’Banion–Elverta double-circuit transmission line. This action would require a new right-of-way (ROW) (125 feet wide) for the transmission line. Additional access roads (15 feet wide) may be required.
Realignments are proposed for two locations. Realignment is defined as a route deviation of an existing transmission line. The route deviation would be sited outside of the existing ROW. The purpose for the realignments would be to reduce impacts to land use. One realignment for the Proposed Action would call for the construction of a new transmission line (2.8 miles) parallel to the existing O’Banion–Elverta transmission line, approximately 17 miles southeast of the O’Banion Substation. The realignment would avoid encroachment to the Pleasant Grove Cemetery. Conductors for the existing O’Banion–Elverta transmission line would be transferred to the west on 14 proposed new structures. The proposed new conductors would be strung along the existing structures to the east. This would avoid transmission line conductors crossing one another.
Western currently operates two transmission lines (2.8 miles) in adjacent ROWs (O’Banion–Elverta double-circuit, 230-kV line and Cottonwood–Roseville single- circuit, 230-kV line) between Keys Road and Elverta Substation. The total width of the two adjacent ROWs is 225 feet. There is no space to expand the ROW to add a third transmission line without impacting residences. Due to these ROW constraints, Western would realign five miles of the Cottonwood–Roseville single-circuit, 230-kV transmission line. A new transmission line between Keys Road and Elverta Substation would be constructed in place of the realigned Cottonwood–Roseville line. The realignment would deviate from the existing Cottonwood–Roseville transmission line at Keys Road and traverse eastward approximately 1.7 miles using new 125-foot-wide ROW along the south side of Keys Road. There it would angle south, paralleling the west side of the existing Pacific Gas & Electric Company (PG&E) Rio Oso–Brighton double-circuit, 230-kV transmission line for 3.3 miles. At that point, it would rejoin the existing route of the single-circuit, 230-kV Cottonwood–Roseville transmission line. This would eliminate the need for two sections of the existing Cottonwood–Roseville transmission line that would be abandoned in place. These sections are approximately 1.4 miles and 2.2 miles in length.
Alternative 1 would reconductor 99.2 miles of single- and double-circuit, 230-kV transmission lines on 820 structures from O’Banion Substation to Tracy Substation. About 199 structures would be replaced. Work would occur in three phases: O’Banion Substation to Elverta Substation; then Elverta Substation to Hurley Substation; and finally, Hurley Substation to Tracy Substation. Reconductoring activities for Alternative 1 would be the same as reconductoring activities described for the Proposed Action. While Alternative 1 would provide relatively less voltage support and capacity than the other action alternatives, it would relieve the system especially during periods of high load demand.
Alternative 2 is identical to the new transmission line construction and realignment activities of the Proposed Action, including new ROW (125 feet wide) and access roads (15 feet wide). Alternative 2 includes new construction of 26.6 miles of double-circuit, 230-kV transmission line between O’Banion Substation and Elverta Substation and realigning 2.8 miles near the Pleasant Grove Cemetery and five miles of the Cottonwood–Roseville transmission line.
Alternative 2 would require an estimated 50.9 acres of new access roads. Both realignments are described in the Proposed Action. Alternative 2 would meet the Purpose and Need by providing new transmission line between O’Banion Substation and Elverta Substation, and by providing additional voltage support for the Sacramento Area. The new line would eliminate limitations on the flow of power (generation) to Sacramento during n-1 and n-2 contingencies. 1
Alternative 3 would require new construction of 46.2 miles of double-circuit, 230-kV transmission line from Elk Grove Substation to Tracy Substation along Segment E1. The route would parallel Western’s two existing transmission lines (Hurley–Tracy No. 1 and No. 2) to the west. A new 125-foot-wide ROW adjacent to existing transmission line ROWs would contain about 225 new structures. Alternative 3 would require an estimated 85.5 acres of access roads. Alternative 3 would meet the Purpose and Need by supporting the load and thus increasing voltage support to the Sacramento area.
The No Action Alternative would include operating and maintaining the existing transmission lines. Western would not build or reconductor any transmission lines in the study area relative to voltage support. Implementing this alternative would preclude most short-term environmental impacts associated with construction and reconductoring activities. This alternative would not meet Western’s Purpose and Need. Western may be unable to meet system reliability standards and its contractual obligations.
For more information on Western’s Sacramento Area Voltage Support EIS, please visit our website (click on What’s New), call our toll-free project hotline, request to be placed on the project mailing list, and/or contact the Environmental Project Manager:
Loreen
McMahon
Project
Manager
Western
Area
Power
Administration
Sierra
Nevada
Regional
Office
114
Parkshore
Drive
Folsom,
CA
95630
(877)
913-4440
Toll-Free
(916)
353-4416
Voice
(916)
985-1934
Fax
Send
E-Mail
