OVERVIEW of Mid-Atlantic Resiliency Link (MARL) 500kV / Gore - Doubs - Goose Creek (500kV)
These lines are part of the over $5 billion in new transmission lines approved by PJM to support the projected 7,500 megawatts of new data centers in Northern Virginia as well as to compensate for the planned retirement of 11,000 MW of fossil fuel generation in its eastern region. This project was initially awarded to NextERA in December of 2023 at a cost of approximately $1.06B. In August of 2024, PJM accommodated a re-route requested by Loudoun County . This added $167M to the overall cost (a 20% increase) bringing the total to $1.2B. At that time project was split into three segments and assigned to NextERA, First Energy and Dominion Energy. In January of of 2026 the cost of the NextERA segment of the project doubled from $440.95M to $844.80M, bringing the total cost of the project to $1.63B . This is before applying the 9.8% incentive rate awarded by FERC.
The MARL/Gore-Doube-GooseCreek line starts at the 502 Junction and is a giant 154 mile extension cord from West Virginia’s coal fired plants - specifically the Fort Martin Power Station, Harrison Power Station and the Mitchell Power Station - into the ‘heart’ of Loudoun County's data center alley in Northern Virginia. All three of these generators are coal-fired and together total nearly 5,000 MW of capacity and according to PJM have excess capacity that can be tapped to support the development of new data centers (@117 )and expansion of the existing 200 data centers. Four transmission companies will be building segments of this line : NextERA, FirstEnergy, Potomac Edison and Dominion across four states.
Both of the First Energy of power plants are reaching the end of their useful life within the next 10 to 15 years, at best this is a partial / temporary solution to the present energy shortfall in Virginia's data center region. A better solution would be for the Data Centers to locate closer to the generation plants with excess capacity or to build additional generation in Virginia to meet the demand.
PJM doesn't have a transmission reliability issue, the region has a lack of base load generation in Virginia issue.
If approved in all 4 states, this line will traverse :
- 3 Counties in Virginia: Frederick, Clarke and Loudoun
- 2 Counties in Pennsylvania: Greene and Fayette
- 5 counties in West Virginia: Preston, Monongahela, Mineral, Hampshire and Jefferson
- 4 Counties in Maryland: Garrett, Allegheny, Frederick and Montgomery
NextERA 's 107.5 mile portion of the transmission line in a new 200' easement (takings of at least 2,606 acres of private property) is called Mid-Atlantic Resiliency Link (MARL) through :
- 2 Counties in Pennsylvania: Green and Fayette counties
- 4 Counties in West Virginia : Preston , Monongahela, Mineral and Hampshire counties
- 1 County in Virginia: Frederick County
- 2 Counties in Maryland: Garrett and Allegheny counties
Next ERA Project Maps can be found here: MARL Project Map
The Woodside substation proposed to be in Clear Brook, is part of NextERA's portion of the MARL / Gore-Doubs-Goose Creek Project. This proposed 500kV transmission substation is to manage / maintain the voltage level of the MARL/Gore-Doubs-Goose Creek line to compensate for the voltage losses that HVAC transmission lines incur over large distances.
First Energy's 44 mile portion, proposed to be within the existing easement, with new easements through some areas, is called Gore-Doubs-Goose Creek it traverses :
- 1 County in West Virginia: Jefferson
- 3 Counties in Virginia: Frederick, Clarke and Loudoun
First Energy Project Maps can be found here:
Note for Frederick and Montgomery properties in Maryland, south of Doubs - the project will result in there being 3 - 500kV and 2 - 230 lines in the ROW:
- The Maryland Fact Sheet says : "Removing two side-by-side structures that support an existing 500-kV line and two existing 230-kV lines and installing three side by-side structures that will support five lines (the existing lines plus two new 500-kV lines) for approximately eight miles."
Dominion Energy is building a segment in eastern Loudoun from the Potomac River to the Golden Substation this segment is approximately 3 miles and will be entirely within the existing easement. This piece is part of the Line #514 Corridor Upgrades which replaces the one 60 year old 500Kv line with three 500kV lines.
At the request of Loudoun County, PJM moved a portion of the transmission line farther out into north western Loudoun County and into Maryland. The Alternate MARL Route was approved by PJM in August of 2024, this route crosses 11 miles of Northwestern Loudoun along the Potomac River, crosses the Potomac River into Maryland and runs through Frederick and Montgomery counties in Maryland before crossing the Potomac River back into Eastern Loudoun County near Ashburn, home to Data Center Alley. This added $167M in cost (20% increase) , pushed the in-service date to 2032 , added and assigned the additional segments First Energy.
This transmission line will also cross the Monongahela National Forest, Appalachian National Scenic Trail, Chesapeake & Ohio Canal National Historical Park, Harper's Ferry National Historical Park, Potomac Heritage National Scenic Trail and it will run parallel down the view shed of the Potomac River.
