How 2 political outsiders led the push for Maryland’s first data center ban

Bryan Cornell and Krissy Flatau never considered themselves to be politically engaged. Then came word of plans to build a hyperscale data center campus next to their Harford County homes.

Each had long enjoyed the kind of quiet life that draws people to this bucolic corner of northern Maryland. Cornell lives on 17 acres in Joppa, raising two children plus a few horses and goats on land his grandfather bought in the 1960s. Flatau lives on a centuries-old horse farm a quarter-mile down the road.

In April, rumors of a proposed new development caused them to consider moving. It called for converting a 275-acre golf course abutting their homes into one of Maryland’s largest data center projects.

“I was like, you know what? Screw this,” Cornell said. “I’m not being forced off my land. We’re going to fight back.”

Cornell and Flatau started a movement, dubbed “Our Land. Our Home. Our Harford.” They organized meetings in the basement of a Baptist church, mobilized thousands on Facebook and distributed lawn signs that still line the roads in Joppa.

By June, the anti-data center uprising that had been building throughout Maryland produced one of its biggest victories when Harford became the state’s first county to permanently ban data centers.

It remains the only Maryland county to have done so, though the town of Chesapeake Beach in Calvert County, population 6,500, approved a permanent ban in late August. Other counties in the state have gone only as far as imposing moratoriums.

The grassroots effort in Harford shows how the backlash against data centers has turned ordinary residents into activists, organizers and a potent political force. What galvanized Cornell, Flatau and others like them was deeply personal: a fear that the tech facilities’ potential environmental impacts, noise and sheer scale posed an existential threat to the character of their communities.

“It’s so beautiful and peaceful,” Flatau said one afternoon in Cornell’s driveway, facing a field where two horses roamed. “It’s mind-blowing that someone would want to destroy that beauty.”

The ban, proposed by Republican County Executive Bob Cassilly and passed unanimously by the County Council, broadly prohibits data centers in all zoning districts. It faces headwinds, including potential legal challenges and the possibility that the state could pass a law overriding it.

Similar battles over land use, zoning and development have erupted before in Harford, a red county northeast of Baltimore where residents fiercely guard its rural landscape. The data center fight, though, was amplified by fears over the industrialization of agricultural land and the tech facilities’ massive consumption of water and energy.

Harford’s hard-line approach to data centers could cost the county a “generational opportunity” to attract emerging industries, create jobs and generate tax revenue, said Kelly Schulz, CEO of the Maryland Tech Council.

“Because there was a project that nobody liked in their community, they just said, ‘No, we’re not having data centers at all.’ When in reality, they could say, ‘Let’s take a look at where those locations could be in our jurisdiction that would be more appropriate,’” Schulz said.

The preliminary proposal, which was never formally submitted to the county, called for building a seven-building, 672-megawatt data center campus on Joppa’s Mountain Branch Golf Course, according to site plans and email correspondence obtained by community members.

The project’s website said the campus would generate much of its power on-site, rather than drawing from the local electrical grid; limit public water use and nighttime noise; and preserve five acres of farmland for every acre developed. It was touted as one of the largest private infrastructure investments in Maryland’s history, promising thousands of skilled-trade jobs and substantial recurring tax revenue.

“We did not take a standard data center blueprint and try to force it onto Joppa,” Bill Vasilakopoulos, the owner of Mountain Branch Golf Course, wrote on the website. “Every major technical decision was designed to protect the residents who live here.”

Vasilakopoulos declined a request for additional comment.

Starting a movement

Cornell and Flatau were unlikely leaders of Harford’s anti-data center movement.

Cornell, 50, had voted before but otherwise didn’t take much interest in local politics, preferring to hunt, golf and play baseball. A superintendent for a large developer, he said he doesn’t oppose development or even data centers, as long as they’re built in communities that want them.

Flatau, a 56-year-old school library employee, grew up around politics but wanted little to do with it. Her mother, former county executive and gubernatorial candidate Eileen Rehrmann, spent years in the public eye, which left Flatau wary of the spotlight.

The neighbors had never met until April, when Cornell started sending mass texts around the community about the Mountain Branch proposal. Soon, they immersed themselves in a campaign to stop it.

“You cannot take advantage of communities and people, and you can’t go in and ruin their quality of life,” Flatau said. “People’s homes are their sanctuary.”

Cornell hosted a community meeting at his horse barn overlooking the golf course’s 14th hole, which dozens attended. Flatau toured a neighborhood near a data center in Virginia and posted videos of the facility’s incessant hum on social media, where they went viral. Their Facebook group grew into the thousands.

Cornell had never attended a council meeting before, while Flatau hadn’t been in many years. Soon they were both regulars, speaking out against data centers at every opportunity. Hundreds of residents filled the chambers alongside them.

“I’ve never seen a community come together on a topic like this,” Cornell said. “Our livelihoods, our health, our humanity were being attacked.”

A ban

At first, Harford appeared poised to go the way of many other Maryland counties and enact a data center moratorium.

Around the time residents learned of the Mountain Branch proposal, the council introduced a bill calling for a 180-day pause. Lawmakers said they wanted to give county officials time to study the industry and determine how to regulate it.

But Cassilly, a first-term county executive facing a primary challenge from Council President Patrick Vincenti, believed a temporary moratorium didn’t go far enough. He responded with legislation calling for an outright ban.

Cassilly said his administration had concerns about data centers as early as April 2025, when he sent planning and zoning officials to study Northern Virginia’s data center hub. The officials reported that although the facilities can generate tax revenue windfalls, they also drive up demand for water and energy.

Cassilly said those energy demands were incompatible with the state’s resources, as Maryland imports much of its electricity and has a goal of 100% clean energy by 2035.

“A moratorium is a waste of time because in the end, we don’t have the power anyway,” Cassilly said. “So let’s just skip that step and do the ban.”

Cassilly also called the Mountain Branch proposal “outrageous” because it would put a data center in an agricultural zone, near residences and in an area served by wells and septic systems.

“If you were in support of these things, I can’t imagine a more foolhardy way to proceed than to unveil it at Mountain Branch,” he said.

The grassroots movement aligned behind Cassilly’s proposal. Some went door-to-door distributing lawn signs that read, “NO DATA CENTERS.” Students at Flatau’s school wrote letters asking the council to support the measure. Dozens spoke out the night of the council’s vote, with the line extending out the door and down the block.

With Cornell and Flatau standing beside him, Cassilly signed the ban into law. Two weeks later, he won the Republican county executive primary.

Cornell and Flatau said their joy and relief were short-lived. Their minds quickly turned to the potential fights ahead: Laws could change. The county’s ban could face a lawsuit. The Mountain Branch proposal could find a new path forward.

Among their biggest priorities is organizing ahead of the state’s next legislative session in January, when data centers are likely to be a central issue and lawmakers could undercut local efforts to curtail them.

“We are the ‘data center people’ now,” Cornell said, “and it’s not going to stop.”