WaterMark / Jurisdictions / Prince William County, VA
Prince William County, VA: Data Center Water Impact
Reference data for evaluating a data center proposal in Prince William County, VA. Every figure below is a stored value with its primary source attached. Facility-scale results are produced by the assessment tool.
Water supply
| Metric | Value | Source / basis |
|---|---|---|
| Water utility | Prince William County Service Authority | Utility of record |
| Supply source | Occoquan Reservoir | Utility of record |
| Treatment capacity | 50 MGD | Water stress: WRI Aqueduct 4.0, HUC-8 02070011. Utility: PWCSA. |
| Water rate | $8.00 / 1,000 gal | Prince William County Service Authority published rate schedule |
| Watershed stress | High (3.4 / 5) | Water stress: WRI Aqueduct 4.0, HUC-8 02070011. Utility: PWCSA. |
Watershed consumptive use
Basin: Lower Potomac (HUC-8 02070011). Figures are consumptive use, not withdrawal, because evaporative data center loss is consumptive. USGS data year 2020.
| Category | Consumptive use (MGD) | Share of basin |
|---|---|---|
| Residential | 8 | 39.6% |
| Thermoelectric power | 5 | 24.8% |
| Industrial | 1.5 | 7.4% |
| Irrigation | 1.5 | 7.4% |
| Mining | 0.2 | 1.0% |
| Existing data centers | 4 | 19.8% |
| Total | 20.2 | 100.0% |
Total is the sum of the categories listed above. Shares are each category divided by that total. Source: USGS Water Use 2020, Prince William County.
Grid generation water (Scope 2)
Generating the electricity a data center consumes evaporates water at the power plant. That volume is real, it is attributable, and it is excluded from most corporate "water positive" accounting. On a thermal grid it is frequently comparable to the facility's own cooling water.
| Metric | Value | Source / basis |
|---|---|---|
| Grid region | PJM Interconnection | PJM |
| Electric utility | NOVEC / Dominion | Utility of record |
| Grid water intensity | 0.42 gal / kWh | Macknick et al. 2012 × PJM GATS EY2024 |
| Local peak demand | 1,500 MW | PJM |
| Modeled rate impact | 12% to 22% | See methodology |
Where this water is consumed: PJM grid plants serving Prince William are distributed across MD, VA, PA, OH, WV. Scope 2 water is consumed largely outside the local Potomac basin.
Run this county at your facility size. The assessment tool computes direct (Scope 1) and indirect (Scope 2) water for a specific load, cooling system, and mitigation stack, with the same citations attached.
Reducing the footprint here
A high stress reading is a design constraint, not a verdict. Closed-loop and dry or hybrid cooling, adiabatic assist, immersion, and reclaimed or non-potable sourcing each move the direct number, and siting against a cleaner grid mix moves the indirect number. The solutions catalog lists each option with its water reduction, its energy and cost tradeoff, and its source.
Regulatory and siting status
Manassas / Gainesville cluster. The flagship PW Digital Gateway (~2,100 acres) is dead: the VA Court of Appeals upheld voiding its rezoning (31 Mar 2026, improper public notice), the County withdrew from appeals, and QTS terminated the project and withdrew its Supreme Court petitions on 2 Jul 2026. Five days later, on 7 Jul 2026, the Board denied the ~1,940-acre Dulles South Innovation Center comprehensive plan amendment 8-0. A countywide zoning text amendment that would shrink the Data Center Opportunity Zone Overlay District and end by-right development is pending; the Planning Commission reheard it 9 Sep 2026 after a public-notice defect, with a Board hearing anticipated 22 Sep 2026. Less saturated than Loudoun; litigation friction now proven material.
- Hyperscale activity
- Contested siting
Sources: Water: Prince William Service Authority. Grid: PJM. Recent: PWC ZTA 2024-13. Digital Gateway: Bisnow, 3 Jul 2026. Dulles South denial: Data Center Knowledge, 6 Aug 2026. Overlay ZTA: InsideNoVa, 29 Jul 2026.
Comparative siting scores for this county, alongside every other county tracked, are on the US Siting Matrix.
Related counties
| County | Water source | Watershed stress |
|---|---|---|
| Loudoun County, VA | Potomac River / Goose Creek Reservoir | High (3.4/5) |
| Henrico County, VA | James River | Medium (2.6/5) |
| Mecklenburg County, VA | Roanoke River / Buggs Island Lake | Low-Medium (1.8/5) |
| Spotsylvania County, VA | Rappahannock River | Medium (2.4/5) |
| Frederick County, VA | Shenandoah River + Anderson Lake | Low-Medium (2/5) |
How these numbers are derived
Assumptions, formulas, and the full source list are in the methodology. WaterMark is published by Standard Water Corp and is not affiliated with any data center developer, utility, or government agency.