625/650 Line Upgrade

This major transmission line serves the areas of Northstar, Kings Beach, Tahoe Vista, Tahoe City and Squaw Valley and is one of the oldest power lines in the state of California. The $46 million project will improve reliability, even if a portion of the closed loop system is damaged, by allowing greater load transfer and switching ability that benefits the entire system. We are currently in the permitting phase with TRPA, USFS and others, and hope to begin construction in 2014.

Project Description

The proposed 625/650 Electrical Line Upgrade Project is located in northeastern Placer County and southeastern Nevada County. The project consists primarily of an upgrade of the 625 and 650 power lines and associated substations from 60 kV to 120 kV to allow the entire transmission loop to operate at 120 kV. The project consists of six primary components:

Removal of the existing 625 line and construction of a new, rerouted 625 line

Rebuild of the existing 650 line

Realignment of two short segments of the 650 line and removal of the re-routed segments

Rebuild of the Northstar Tap into a Fold allowing for uninterrupted service during an event

Rebuild a 1.6 mile long section of the existing 132 line

Upgrade, modification and/or decommissioning of six substations and/or switching stations

The project components are predominately located on lands managed by the U.S. Dept. of Agriculture, Forest Service (USFS); these lands are located in the Lake Tahoe Basin Management Unit and Tahoe National Forest. Portions of the project are also located in the Town of Truckee and the unincorporated communities of Kings Beach and Tahoe City, and on lands within the Martis Creek Lake Recreation Area, managed by the U.S. Army Corps of Engineers.

Project Benefit

The key benefit of the 625/650 Line Upgrade Project is to provide reliable service even if a portion of the closed loop system is damaged (known as a single-contingency outage).

Upon completion of the upgrade project, if any one line in the system fails (due to snow load, damage, etc.), the rest of the closed loop system will be able to maintain the current maximum system loads.

Service reliability would be significantly increased reducing the possibility of brownouts and full outages.

Other Benefits

Reduce dependence on the Kings Beach Diesel Generation Station. This source is used for backup only during single-contingency events but operations are limited due to environmental restrictions. Once the upgrade is completed, this source would only be used for rare multi-contingency events.

Reduce fire hazards and outage durations. Rebuilding the transmission lines with new, dark-colored steel poles and polymer insulators will dramatically reduce the number of outages experienced over the next decade, as well as blend in with the environment..

Provide reliable access to the 625 line. This line was originally designed and constructed to blend in with the existing vegetation and terrain. While initially aesthetically pleasing, safe and reasonable access for repair and maintenance—especially during heavy snow—can actually be more damaging to the environment. Rerouting the alignment of some of the line to more closely follow existing roadways would address this issue.

Provide additional normal capacity for projected future loads. The system must be capable of supplying peak loads (i.e., demand) whenever they occur. Also, industry standards call for the system to supply peak loads with any one component out of service (i.e, single contingency).

Economic Impact. The $46 million project would be constructed over a six-year period in three phases (see below) generating construction jobs and spending in the State.

The Need

The existing 625 line experiences the most outages in the North Lake Tahoe transmission system due to snow loads and downed trees.

Fire danger is a constant threat because the line is entirely constructed with wooden poles. Approximately 610 wooden poles would be replaced with approximately 570 new, dark-colored steel poles.

Due to the existing line’s placement, it is difficult to access for emergency and routine maintenance.

If the existing 60kV transmission line from Truckee to Kings Beach (known as the 650 line) is damaged, the system will not be able to provide necessary capacity to Kings Beach.

If the 60kV transmission line from Tahoe City to Squaw Valley (known as the 629 line) or the 120kV transmission line from Truckee to Squaw Valley (known as the 132 line) is damaged, the system will not be able to provide necessary capacity to Tahoe City.

Background

Liberty Utilities (dba California Pacific Electric Company or CalPeco) purchased the California electric service territory from Sierra Pacific Power Company/NV Energy in January 2011. The purchase included the existing electrical transmission system.

The transmission system serving the North Lake Tahoe area is a loop comprised of 60kV and 120kV transmission lines running from Truckee to Squaw Valley to Tahoe City to Kings Beach and then back to Truckee. These five transmission lines are identified on the accompanying map and are collectively known as the 625/650 line.

In 1996, a Sierra Pacific Power Company study identified the need to upgrade the existing 625/650 transmission line for reliability purposes and proposed a continuous construction timeline.

In 2011, Liberty’s engineering consultant confirmed the 1996 findings but recommended a three-phased construction approach to reduce the project’s impacts and ensure success.

Phases of the Project

Phase 1: This is the most critical and immediate phase. The existing 650 line (currently at 60kv) will be upgraded to allow for future operation at 120kV in Phase 2. The rebuild will use existing right-of-way and alignment as much as possible, and will include new structures, structure spacing and structure types and work at the Tahoe City Substation to address low-voltage conditions.

Phase 2: The purpose of this phase is to continue upgrades that allow the 650 line to operate at 120kV and involves the portion of the loop from North Truckee Substation to Kings Beach Substation. Work at the Kings Beach Substation would also occur. The Brockway Substation, (located within 100 yards of the Kings Beach Substation) would be decommissioned to address multiple issues with it, including its space limitations and its location within a residential area.

Phase 3: This phase would complete the full 120kV loop rebuild and the system would be able to operate at 120kV. The threat of outages due to loss of either the 132 line or the 650 line is eliminated. This last phase includes an extensive rebuild of the 625 line requiring relocation out of its current right of way between Tahoe City and Kings Beach.

Current Status

CalPeco (dba Liberty Utilities) has applied for permitting of the project under a Memorandum of Understanding (MOU) with the following lead agencies:  Tahoe Regional Planning Agency (TRPA), U.S. Department of Agriculture Forest Service-Lake Tahoe Basin Management Unit, and the California Public Utilities Commission.   These three agencies are responsible for the review of the application, solicitation of public comment, and recommendation to the TRPA Governing Board for final approval and/or permitting.

625/650 Electric Lines Upgrade Project Informational Meetings will be held on Tuesday, December 10th from 2-4 p.m. at the USFS Tahoe National Forest Truckee Ranger District Office at 10811 Stockcrest Springs Road, Truckee, CA and from 6-8 p.m. at the North Tahoe Events Center, 8318 No. Tahoe Blvd., Kings Beach, CA. 

Additionally, the proposal will come before the Tahoe Regional Planning Agency’s Advisory Planning Commission on December 4 and the TRPA Governing Board on December 18.  Public comment will be taken at both meetings. Visit www.trpa.org for meeting locations and times.

 

Project FAQRead Our Press ReleaseDownload Project MapVisit the Tahoe Regional Planning Agency Website

Project Summary

Project Proponent: 

California Pacific Electric Company (CalPeco) dba Liberty Utilities.  CalPeco purchased the electric service territory and assets from Sierra Pacific/NV Energy in January 2011, and currently serves approximately 49,000 electric customers in the north and south shores of Lake Tahoe.

Project Location: 

Northeastern Placer County and southeastern Nevada County, California.

Project Description: 

These major transmission lines (known as the 625 and 650 power lines) serve the areas of Northstar, Kings Beach, Tahoe City and Squaw Valley and are some of the oldest in the State of California. 

Project Benefit: 

Upgrading the lines will improve reliability, even if a portion of the closed loop system is damaged, by allowing greater load transfer and switching ability that benefits the entire system.

Proposed Project: 

Upgrade of the existing 625 and 650 power lines and associated substations from 60 kilovolt (kV) to 120 kV to allow the entire transmission loop to operate at 120 kV. 

Project Components: 

  1. Removal of existing 625 line and construction of a new, rerouted 625 line
  2. Rebuild of the existing 650 line
  3. Realignment of two short segments of the 650 line and removal of the re-routed segments
  4. Rebuild of the Northstar Tap into a Fold (allows for service to be maintained at a substation in the event of an interruption anywhere in the line)
  5. Rebuild of a 1.6 mile long section of the existing 132 line
  6. Upgrade , modification, and/or decommissioning of six substations and/or switching stations

Project Need: 

As far back as the 1980s, the need to upgrade the 625 and 650 lines was identified.  These lines often operate at maximum capacity and must be supplemented by diesel generation to meet peak loads.  The aging power lines were never designed to provide a reliable closed loop system which would reduce both the frequency and impact of outages, nor was it designed to carry the current peak load demands.

Project Timeline: 

CalPeco is currently in the permitting stage.  Once permits are obtained, construction can begin tentatively scheduled in 2014.  The project will be constructed in 3 phases over an estimated six-year period.

Project Status: 

CalPeco has applied for permitting of the project under a Memorandum of Understanding (MOU) with the following lead agencies:  Tahoe Regional Planning Agency (TRPA), U.S. Department of Agriculture Forest Service-Lake Tahoe Basin Management Unit, and the California Public Utilities Commission.   These three agencies are responsible for the review of the application, solicitation of public comment, and recommendation to the TRPA Governing Board for final approval and/or permitting.  625/650 Electric Lines Upgrade Project Informational Meetings will be held on Tuesday, December 10th from 2-4 p.m. at the USFS Tahoe National Forest Truckee Ranger District Office at 10811 Stockcrest Springs Road, Truckee, CA and from 6-8 p.m. at the North Tahoe Events Center, 8318 No. Tahoe Blvd., Kings Beach, CA.  Additionally, the proposal will come before the Tahoe Regional Planning Agency’s Advisory Planning Commission on December 4 and the TRPA Governing Board on December 18.  Public comment will be taken at both meetings.  Visit www.trpa.org for meeting locations and times.

Project Environmental Impacts.

The proposed project’s environmental document addresses scenic resources, agricultural and forestry resources, biological resources, recreation, earth resources (geology, soils, seismicity, land capability and coverage), hydrology and water quality, cultural resources, hazardous materials, transportation, parking and circulation, air quality and climate change, noise and vibration, socioeconomic and economic justice, public services and utilities, and growth-inducing impacts.  Mitigation measures and alternatives are identified to address each of the potential impacts.

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