Harrisonburg - Endless Caverns 230kV Double-Circuit Line

In our continued commitment to provide safe and reliable power to area customers, Dominion plans to replace and add an additional 230 kilovolt (kV) transmission line between its existing Harrisonburg and Endless Caverns Substations. With the addition of this new line, residents and businesses in the Shenandoah Valley, Rockingham County and City of Harrisonburg areas will benefit from added capacity and enhanced reliability along the I-81 corridor and in Rockingham County’s research and manufacturing growth area.

Between 2000 and 2010, the City of Harrisonburg experienced a 20.9% increase in population. By 2015, forecasted conditions could jeopardize the mandatory reliability standards that Dominion is required to meet as set by the North American Electric Reliability Corporation (NERC).

Project Details

Project Description

Transmission Line Work

  • The 20-mile overhead line project will utilize the existing right-of-way corridor which extends from the Harrisonburg Substation to Endless Caverns Substation (see map).
  • The new, double-circuit, monopole structures will carry both lines and replace current H-frame structures in the existing rights-of-way.

Substation Work

Harrisonburg Substation (Fall 2013)

  • Additional .35 acres of Dominion property will need to be fenced
  • Additional equipment will provide increased reliability through a second interconnection with the Endless Caverns Substation

Endless Caverns Substation (Winter 2013)

  • Additional 6.8 acres will need to be acquired
  • Complete rebuild of the transmission portion of the station will better interconnect with Harrisonburg Substation and enhance reliability
Project Benefits

Dominion’s new line project will:

  • Add needed capacity along the I-81 corridor and in Rockingham County’s research and manufacturing growth area,
  • Comply with mandatory NERC Reliability Standards,
  • Help strengthen the electrical grid, and
  • Take advantage of the existing corridor.

View a presentation to learn more about the need for this project.

Project Timeline
  • March 2012 — Outreach to State and Local officials
  • Spring/Summer 2012 — Public outreach, letters, website, open house
  • August 2012 — Submitted application with the State Corporation Commission for consideration
  • December 2012 —  Received final order from SCC approving construction
  • May 2013 — Community outreach and notification of intent to construct
  • Fall 2013 — Construction scheduled to begin
  • June 2015 — Target date to energize transmission line
Contact Us

Contact us if you have questions or concerns about the Harrisonburg-Endless Caverns project.

Questions and Answers

What is an easement? Do I still own my property?

Yes, the property owner still owns the land. Easement agreements provide Dominion with a specified set of rights needed to construct, operate and maintain electric facilities across private land.

Will Dominion require additional right-of-way?

The new line will utilize existing right-of way, however crews will extend the fence line along Dominion-owned property at the Harrisonburg Substation approximately 1/3 of an acre, while additional land will need to be acquired at the Endless Caverns Substation to support construction of the enhanced facility.

How will the completion of this project benefit me as a resident?

The new line decreases the likelihood of line overloads and low voltage conditions affecting area residents and businesses in the future.

What is the electric transmission grid and how does it serve local customers and electric cooperatives?

The electric grid is the network of power lines that carries electricity from power plants to residential, industrial and commercial customers. To work effectively, electricity must at all times flow safely and reliably throughout the grid so the power is available when needed. Aging infrastructure, combined with a rise in domestic electricity consumption, has forced experts to critically examine the status and health of the nation's electrical systems. A ten-part series of stories from National Public Radio has been published on, examining the costs, the politics and other challenges of upgrading the country's electricity grid. Learn how the electric grid operates and how power gets to your home.

What is the cost of adding this new line?

Preliminary estimates are $70 million to construct and energize the new line.

Will the new towers look the same as what’s already in the right-of-way?

The new structures are double-circuit monopole structures which are approximately 35-feet taller than the existing structures.  A diagram of the towers is available on our Fact Sheet.

What will be the environmental impact of construction of the line?

As part of our regulatory applications, Dominion completes an evaluation of potential environmental, cultural, and historical impacts of the project. Dominion works with many local and state agencies to complete these evaluations and mitigate any impacts. The company also submits annual Erosion and Sedimentation (E&S) Control Specifications for the construction and maintenance of transmission lines to the Virginia Department of Conservation and Recreation for review and approval. This project will be submitted for approval prior to construction. Our contractors receive copies of the E&S specifications and any additional permit conditions prior to construction and are directed to meet any requirements. The right-of-way will be rehabilitated when construction is complete.

Should I be concerned about Electric and Magnetic Fields?

Dominion is sensitive to public concern about possible health effects from exposure to electric and magnetic fields (EMF). Dominion includes data on the levels of both electric and magnetic fields produced by proposed facilities in all applications submitted with the SCC. We continually monitor EMF research and speak to our customers and employees regularly to share the latest information available.

The Virginia SCC, which regulates the construction and operation of electric transmission lines of 138kV and above, considers EMF in every application. Hearing Examiner’s remarks from recent proceedings are below.

  • March 23, 2009 Beaumeade-NIVO (Case Number PUE-2008-00063) Report of Michael D. Thomas, Hearing Examiner concludes that "… electric transmission line electromagnetic fields do not represent a human health hazard.”
  • May 4, 2010 Hayes-Yorktown (Case Number PUE-2009-00049) Report of Deborah V. Ellenberg, Chief Hearing Examiner, states, “I find that EMF has not been identified as a carcinogen for human beings despite extensive study over many years, and there is, therefore, no basis on which to prohibit the Company from authorizing appropriate uses of its right-of-way.”
  • August 23, 2011 Hollymead (Case Number PUE-2011-00015) Report of Michael D. Thomas, Hearing Examiner, states, “The proposed facilities do not represent a hazard to human health, which finding is consistent with the Virginia Department of Health’s report entitled Monitoring of Ongoing Research on the Health Effects of High Voltage Transmission Lines (Final Report) dated October 31, 2000.”

The Virginia Department of Health in its final report evaluating EMF research concluded:

"Based on the review and analysis of the exhaustive literature review and other research projects completed under the EMF-RAPID program, the Virginia Department of Health is of the opinion that there is no conclusive and convincing evidence that exposure to extremely low frequency EMF emanated from nearby high voltage transmission lines is causally associated with an increased incidence of cancer or other detrimental health effects in humans. Even if it is assumed that there is an increased risk of cancer as implied in some epidemiologic studies, the empirical relative risk appears to be fairly small in magnitude and the observed association appears to be tenuous. The studies published in the literature lack clear demonstration of a cause and effect relationship as well as a definitive dose-response gradient."

Additional information:

Will Dominion repair damage due to construction?

Yes. Our easement agreements allow us access to private roads of property owners crossed by the right of way. The company, at its expense, will repair any private roads damaged by Dominion or its contractors during construction of the line or during future maintenance. In addition, we will reimburse property owners for crop damage, and repair or replace fences or gates if we damage them.

Can Dominion build a portion or the entire line underground?

Overhead lines have proven to be the best choice for providing safe, reliable and economical energy to our customers. Underground transmission lines are not as desirable from an operational point of view. The duration of outages for underground transmission lines is significantly greater compared to overhead lines due to the complexities of locating failures and facilitating repairs. Additionally, labor and material costs for the installation of a 230 kV underground transmission line would be 6 to 10 times more expensive than an overhead option.

Dominion operates a high-voltage network of approximately 6,100 miles of transmission lines. Of this total, only about 1% (67 miles) is comprised of underground cables. At 230 kilovolts, such as the proposed line, there are approximately 2,600 miles of overhead lines and 44 miles of underground cables in our service area. These underground installations are primarily for large water crossings, dense metro areas, or other areas that are not suitable for overhead lines.

Where can I obtain more information on the project’s SCC application?

The Virginia State Corporation Commission may issue dates for a public hearing, in the King George area, with an evidentiary hearing in Richmond thereafter. Citizens are encouraged to participate in the process and provide input. The SCC maintains copies of all documents related to the case. Updates about the status of the application can be found on the SCC website at

To learn more about this process, view our SCC process map.

NYSE : (April 24, 2014) D 71.52 0.46