Cloverhill-Liberty 230kV Line and Substation

Construction Update

Crews have begun preparing the new right-of-way for upcoming transmission line construction. See the "Construction Updates" link below for additional details.

To maintain reliable electrical service in the area, Dominion will construct a new 230,000 volt (230kV) transmission line in Prince William County and the City of Manassas within existing right-of-way. This project includes a new Liberty Substation in Prince William County to be built on land Dominion has already acquired.

On June 29, 2012 Dominion filed an application with the Virginia State Corporation Commission seeking approval for these new facilities. The SCC issued a Final Order on April 17, 2013, approving the line and substation.

Project Details

Construction Updates

Transmission Line Work

Construction of the transmission line is scheduled to begin in May 2014. Prior to actual construction, you may see crews in the right-of-way testing the soil, surveying, clearing trees or vegetation, or installing gravel or timber matting access roads.

Once the right-of-way is cleared and prepared for construction, the following activities may take place:

  • digging and pouring concrete foundations
  • erecting steel monopoles in the right-of-way
  • pulling conductor between the new poles; and
  • restoration the right-of-way after work is complete.

Liberty Substation Work

Work on the substation will take place entirely within the substation or within the transmission right-of-way corridor, and may include:

  • grading and vegetation clearing
  • installation of gravel/timber matting access points
  • assembly and installation of additional equipment
  • restoring the right-of-way and any construction work areas after completion
Route Maps

 Dominion filed an application with the SCC on June 29, 2012, and it was approved on April 17, 2013. 

Photo Simulations

Photo simulations are provided by Truescape and available for viewing via the links below. View an overview of the methodology used to ensure accuracy of the simulations developed.

Simulations for the Cloverhill-Liberty route (view an overview)

Project Description

To maintain reliable electrical service in the area, Dominion plans to construct a new 230,000 volt (230kV) transmission line in Prince William County and the City of Manassas within existing right-of-way. This project includes a new Liberty Substation in Prince William County to be built on land Dominion has already acquired.

  • 2.3 miles between Cloverhill Substation and Cannon Branch Substation – This section will utilize the vacant side of transmission structures to be constructed for the Cannon Branch-Cloverhill line
  • 3.6 miles between Cannon Branch and Liberty Substations  - This section will be built using double-circuit galvanized steel monopoles, replacing the existing single-circuit poles
  • 1.9 miles between the existing Bristers-Gainesville transmission line to the new Liberty Substation - This section will be built using double-circuit galvanized steel monopoles, replacing the existing single-circuit poles
Project Benefits

The new Cloverhill-Liberty project will:

  • Ensure Dominion maintains reliable electrical service in the area,
  • Provide the required infrastructure to support current need and future growth in the region,
  • Resolve projected criteria violations of the mandatory North American Electric Reliability Corporation (“NERC”) Reliability Standards, and
  • Accommodate a requested capacity increase to the Northern Virginia Electric Cooperative (“NOVEC”) Gainesville Delivery Point.
Project Timeline
  • May 2012 -- Community outreach and notification letters mailed to area residents, publicly advertised “Open House Meeting” held to inform community
  • June 29, 2012 -- Filed application with Virginia State Corporation Commission (SCC). 
  • April 17, 2013 -- SCC approval received.
  • Summer 2013 -- Begin preparation of right-of-way for construction of transmission line
  • October 2013 -- Begin site preparation for new Liberty Substation
  • May 2014 -- Begin construction of transmission line
  • November 2015 -- Energize line and substation
SCC Approval Process

The State Corporation Commission (SCC) is responsible for determining the need, route and environmental impact of transmission lines at 138 kV and above in Virginia.

Dominion filed an application with the SCC on June 29, 2012. Documents related to the case number PUE-2012-00065 are made available to the public on the SCC Docket Search section of the SCC website. A Hearing Examiner’s Ruling was issued, which includes a revised Procedural Order.

The SCC Staff Report concluded in January 2013, that the Company has reasonably demonstrated the need for the proposed 230 kV Cloverhill-Liberty Line, double-circuit 230 kV Liberty Loop, and Liberty Substation. Since the proposed route totally uses existing right-of-way, the Staff concludes that the proposed routing reasonably minimizes the adverse environmental impact to the surrounding area and that it is an optimal route.

The SCC issued a Final Order on April 17, 2013, approving the Cloverhill-Liberty 230kV line and substation.

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

Contact Us

Contact us if you have questions about the Cloverhill-Liberty project, or call us toll free at 1-888-757-6698.

Questions and Answers

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

Due to the interconnected nature of the electric transmission grid, all power users in the area rely on Dominion's transmission infrastructure to deliver reliable power. The new 230 kV lines will provide increased operational flexibility and greater system reliability. As an area resident, this means fewer outages, and shorter durations should an outage occur. Additionally, the localities ultimately crossed by these lines will each benefit from the increased property tax revenues paid by Dominion.

What will be the environmental impact of construction of the line and what regulatory requirements does Dominion adhere to?

As part of the SCC application, 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 reasonably mitigate any impacts. The company also submits annual Erosion and Sedimentation (E&S) Control Specifications and an anticipated list of transmission line projects for the construction and maintenance of transmission lines to the Virginia Department of Conservation and Recreation for review and approval. This project will be included in the annual submittal 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.

Our enterprise-wide environmental report describes our commitment to responsible stewardship of natural resources and provides a wealth of information on environmental management and performance. We also invite you to read our Corporate Environmental Policy and our Greenhouse Gas report.

The company’s construction of new transmission line facilities complies with the Chesapeake Bay Protection Act (CBPA) in accordance with 9VAC10-20-150. This Virginia Administrative Code provision provides that construction, installation, operation, and maintenance of electric transmission lines comply with Virginia’s regulations implementing the CBPA if such construction, installation, operation and maintenance adhere to any one of the following:

(i) regulations promulgated pursuant to the Erosion and Sediment Control Law (§10.1-560 et seq. of the Code of Virginia) and the Stormwater Management Act (§10.1-603.1 et seq. of the Code of Virginia),

(ii) an erosion and sediment control plan and a stormwater management plan approved by the Virginia Department of Conservation and Recreation, or

(iii) local water quality protection criteria at least as stringent as the above state requirements.

The company adheres to both items (i) and (ii) by complying with annual Erosion and Sedimentation Control Specifications for the construction and maintenance of transmission lines as reviewed and approved annually by the Virginia Department of Conservation and Recreation.  In addition, the company obtains a Virginia Storm Water Protection permit for each project and we follow required inspection and recordation procedures during construction, which in many cases exceeds CBPA standards. We also make use of matting systems which reduce or eliminate the disturbance to sensitive wetland ecosystems.  For more information visit the Virginia Department of Environmental Quality website on the CBPA.


What is an easement?

Easement agreements (also referred to as "right-of-way agreements") provide Dominion with a specified set of property rights needed to construct/rebuild, operate and maintain electric facilities across real property. At the time the easement is acquired by Dominion, land owners are compensated based on the fair-market value of the property acquired for the easement and any damages to the remainder of the property outside the easement area. The property owner(s) still own(s) the land but the easement rights granted to Dominion are perpetual and run with the title to the land.

Will property owners be compensated when Dominion utilizes the existing easements?

Dominion compensates property owners only at the time a new easement is acquired. New easements will mostly likely not be necessary for the Cloverhill-Liberty project.

Property owners of record when the easements were first acquired were compensated and the easements were filed with county/city records departments.

For a copy of the easement that covers your property, contact your local county or city land records office. Dominion can also provide you with a copy. Email your request to with "Easement request" in the subject line. Allow up to six weeks for processing. For more information regarding Dominion easements, visit our website Right-of-Way page.


How can I learn more about the transmission system, and why new infrastructure is needed?
  • The 21st Century Grid: This July 2010 article from National Geographic magazine describes the electric transmission system, or “grid,” and our modern day energy challenge.
  • The modern electric grid receives power from many sources and types of generation including wind, coal, natural gas, and hydroelectric and others. There is not a one-to-one connection between any fuel source and customer. Get more information on how the grid works.
  • Learn how power gets to your house.
  • Check out the interactive simulations available on the Department of Energy website. You can also see how a few simple changes at home can lower your own consumption - and your bill!
  • So where is all the power going? Find out who the big users are on an information-packed site from Virginia’s State Corporation Commission.


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:

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