Maryland ratepayers are on the hook for $4.3 billion in transmission costs driven largely by data center electricity demand, and a proposed campus near Dickerson would draw tens of thousands of gallons daily from the Potomac River. Those are the stakes behind the Montgomery County Council's 11-0 vote on July 28 to impose an 18-month moratorium on new data center permits.

Here's what the pause means for Potomac-area residents.

Your electric bill

The Maryland Office of People's Counsel released a report in March finding that PJM Interconnection, the regional grid operator, allocated $4.3 billion in transmission capital costs to Maryland from 2010 to 2030. Nearly three-quarters of that spending is driven by load growth, most recently from out-of-state data centers in Northern Virginia and Ohio.

Maryland utilities spent or will spend another $2.8 billion on local transmission projects over the same period, the report found. Transmission costs now make up roughly 10 percent of a typical Maryland customer's electric bill.

Looking ahead, PJM could assign Maryland an additional $5.4 billion in new transmission costs for projects built from 2031 to 2035, according to the same report. PJM forecasts peak electricity demand will grow 42 percent across its region from 2026 to 2036, largely because of data center expansion.

At the July 28 vote, at-large Councilmember Will Jawando, the Democratic nominee for county executive, listed the issues the county would examine during the pause: "noise, water usage, the Potomac River, one that I've been pushing really hard on and I'll mention every time, tax rates," he told WTOP.

At a July 23 committee meeting, Jawando told WTOP that a data center in Montgomery County would currently pay the same property tax rate as a single-family home.

The Potomac River

California-based Atmosphere Data Centers has applied to build a five-building, 360-megawatt campus on 110 acres of industrially zoned land at the former Dickerson coal plant site along the Potomac River, adjacent to the C&O Canal National Historical Park. The plant was decommissioned in 2020.

Atmosphere's cooling system would draw an average of 69,300 gallons of water per day from the river, according to the company's application reported by Bethesda Magazine. The proposed maximum daily withdrawal: 500,000 gallons. For comparison, a typical Northern Virginia data center uses about 18,000 gallons per day, according to a Baltimore County study cited by The Banner.

Atmosphere called the council's vote "disappointing," according to WTOP. CEO Chuck McBride said in a statement to Bethesda Magazine that the company would "fully evaluate the Council's action and determine what it means for the Dickerson project."

The company also plans to use diesel generators as backup power, with emissions controls including selective catalytic reduction and particulate filters.

Jobs: construction vs. permanent

Data centers require thousands of construction trade workers to build but create only about 100 to 200 permanent jobs once operational, according to NPR reporting cited in The Banner's FAQ. A nationwide shortage of approximately 439,000 construction workers means out-of-state crews may fill many of those temporary positions.

No source has provided a specific construction job count for the Dickerson campus.

What happens next

The moratorium, sponsored by Councilmember Evan Glass with support from Jawando and Council Vice President Marilyn Balcombe, runs until early 2028.

A state study on data centers' environmental, energy and economic impacts, conducted by the Department of the Environment, the Maryland Energy Administration and the University of Maryland School of Business, is due to the governor and General Assembly by Sept. 1. The study was authorized after the General Assembly overrode Gov. Wes Moore's veto of the Data Center Impact Study bill in December 2025.

Council President Natali Fani-González said at the July 28 vote, "We need more information, especially from the state."

The Sept. 1 state study is the next major milestone. The council has committed to writing long-term zoning, tax and environmental rules before any new permits are issued.