Sources · data centres
Reels from data-centre construction
Checked 9 November 2026 — Data-centre construction in Loudoun and Prince William counties empties cable reels on a scale few other kinds of work match: each building is wired with medium-voltage feeders, copper distribution, grounding, controls and fibre, all delivered on reels. The steel ones go back to their makers; the wooden ones, by the hundred, need somewhere to go at close-out.
From the reel desk · Checked 9 November 2026
The scale
Loudoun. As of 1 March 2026, the county counts about 233 existing data-centre buildings and some 56.5 million square feet built or under construction. The average existing building is about 234,000 square feet; those permitted since 2023 average about 339,000. More than 10 million square feet was permitted in 2025, a record, and 35.7 million square feet, about 115 buildings, is approved but not built. By-right development ended in 2025, so new projects need a special exception.
Prince William. In 2022 the county had 33 data centres, 5.49 million square feet on 523 acres, with 13 more under construction, 29 of them in the Data Center Overlay District created in 2016. The Digital Gateway, a 2,100-acre proposal near the battlefield, has ended.
Frederick. Quantum Loophole announced a 2,100-acre campus at Adamstown in 2021, on the former Eastalco aluminium works. We have not confirmed its progress.
What a building empties
- Medium-voltage cable on 54 to 84 inch reels, some steel and returnable.
- Copper feeders on 42 to 66 inch nailed reels.
- Branch and control cable on 23 to 36 inch reels, many plywood.
- Grounding conductor on small C-series reels.
- Fibre on small reels, plywood and plastic.
The power lines behind them
Loudoun's transmission page lists the lines being built to supply the load: Aspen to Golden, with two substations near Ashburn; Golden to Mars; BECO to Firehouse in Sterling; Mars to Wishing Star near Brambleton; Morrisville to Wishing Star from Fauquier; and others. Line and substation work empties the largest reels, mostly steel.
At close-out
A campus laydown yard at close-out holds reels from several makers in every size. The routes:
- Steel and returnable reels go back to their makers, with serial numbers and invoices.
- A full truckload of one maker's sound nailed reels may go to that maker's program or Sonoco EcoReel.
- Everything else (mixed brands, plywood, small reels, damaged reels, lagging) goes to the desk.
On large campuses, step 3 is usually most of the yard.
Working on a campus
The desk works to the site's rules: badging, gate times, escort, PPE, the traffic plan. Put the site contact and the rules in the request, and say whether pickups should run during construction (every few weeks) or once at close-out.
What each source leaves behind
| Source | Usual reels | Usually goes |
|---|---|---|
| Data-centre campuses | Large nailed reels of medium-voltage and feeder cable; mid-size reels of fiber | A truckload of one maker's reels to its program; mixed brands and short loads to the desk |
| Fiber and BEAD builds | Small and mid-size reels, a good share of them plywood | Plywood and part loads to the desk |
| Utility line work | Big conductor reels, wooden and steel | Steel back to its maker; wooden reels by program or to the desk |
| Electrical contractors | Building wire on small reels, a handful per job | The desk, pooled into runs |
| Distributors | Every brand and size, emptied at the counter | Sorted by stencil; the rest to the desk on a standing schedule |
| Federal construction | The same reels as any contractor job | The desk, booked around badging and escort rules |
Reels you are likely to have
| Reel | Build | Flange | Traverse | Drum | Lb | Usually carries |
|---|---|---|---|---|---|---|
| C-5 | Nailed wood | 23 | 17 | 12 | 34 | Copper building wire, grounding |
| A-10 | Nailed wood | 30 | 22 | 16 | 66 | Service drop, bare aluminium |
| N-24 | Nailed wood | 36 | 28 | 14 | 83 | Insulated and multiplex cable |
| A-29 | Nailed wood | 42 | 28 | 21 | 154 | Overhead conductor, feeders |
| A-38 | Nailed wood | 48 | 28 | 24 | 212 | Aluminium and ACSR, large feeders |
| A-62 | Nailed wood | 60 | 28 | 28 | 397 | Utility conductor |
| A-76 | Nailed wood | 66 | 28 | 30 | 473 | Heavy conductor |
| S-120 | Steel, returnable | 84 | 36 | 42 | 895 | Transmission and medium voltage |
Other makers' reels differ by an inch or two. All flange sizes · How to measure
Sources
Each opened and read on 9 November 2026.
- Loudoun County, Data Centers: The Loudoun Story: counts as of 1 March 2026: about 233 data centre buildings, 56.5 million sq ft; over 10 million sq ft permitted in 2025; 35.7 million sq ft approved but not built; by-right development ended in 2025
- Loudoun County, Transmission Lines in Loudoun County: status of Aspen to Golden, Golden to Mars, BECO to Firehouse, Evergreen Mills, Global Plaza Extension, Mars to Wishing Star and the Potomac Edison Goose Creek rebuild
- Data Center Frontier, Prince William County weighs proposals that could accelerate data center growth (8 August 2022): 33 existing data centres, 5.49 million sq ft, 13 under construction, 29 in the Data Center Overlay District created in 2016
- Virginia Business, Prince William Digital Gateway data center project officially dies (6 July 2026): rezonings voided in August 2025, affirmed 31 March 2026; QTS withdrew its appeal
- Data Center Frontier, Quantum Loophole plans 2,100 acre data center campus in Maryland (28 June 2021): former Alcoa Eastalco Works site at Adamstown, about 25 miles north of Ashburn