After months of negotiating with a prominent developer who was willing to build a library in Middle River, Baltimore County Executive Kathy Klausmeier ended the discussion.

St. John Properties proposed building a state-of-the-art library in Greenleigh, an upscale new home development in Middle River, and then leasing it back to the county.

Residents, library officials and local representatives enthusiastically supported the project, with more than 1,500 people signing a petition in support. Local representatives, including the area’s longtime councilman, David Marks, lobbied Klausmeier for the project after she became county executive in January.

Marks was furious after hearing the news.

“This announcement is a giant middle finger to the Middle River community,” he said.

The Baltimore County Public Library shared his frustration.

“We are disappointed to hear Baltimore County’s decision to end negotiations to build a library branch in Middle River,” library officials said in a news release Friday afternoon. “Data shows that Middle River is one of the fastest-growing communities, yet it does not have its own library branch. We appreciate the community’s advocacy and support for this project and St. John Properties for its collaboration on creating a 21st century building that would fulfill the library’s vision and the community’s needs.”

Klausmeier said as early as February when she presented the budget that the project was going to be a heavy lift in the current fiscal climate. And Friday, she announced it was not moving forward, citing unexpected headwinds.

“A lease agreement for a significant project like this proposed library would add tens of millions in unanticipated costs for lease payments, equipment, and maintenance over the next several decades, and doesn’t account for the millions in annual staffing costs needed to support a brand-new library branch,” Klausmeier said in a statement.

The county executive, who was appointed after Johnny Olszewski Jr. was elected to Congress, generated applause at the budget announcement for not raising taxes, and has stressed she intends to keep it that way. The new library, she said, could mean raising taxes, especially after predictions by the state that revenues would be lower than expected.

Marks was particularly incensed because the council is considering an administration-backed request for major tax breaks to incentivize development at Metro Center and Security Square Mall — both of which are on the county’s west side.

“The County Council is being asked to subsidize development by the hundreds of millions of dollars elsewhere, but now the County Executive pretends to pinch pennies when it comes to Middle River,” he said. “This is yet another profound disappointment from this administration.”

Josh Sines, president of the Essex Middle River Civic Council, was equally irate, calling the decision “a blatant insult to the taxpayers who have waited far too long for fair investment in their community.”

Sines disputed Klausmeier’s cost estimates and said the developer’s contribution meant the library would cost half of what a traditional build does. He saw it as further evidence that county officials do not prioritize the east side.

The community is currently fighting a landfill’s request to discharge more harmful runoff into the Gunpowder River, as well as flooding issues at waterfront properties. Last summer, residents and their representatives fought for more resources to fend off an infestation of pesky midges. And there are perennial fights for parity when it comes to amenities and county investments.

“Because it’s Middle River,” Sines said, “once again, we are told to wait.”

Klausmeier stressed that the announcement in no way meant the county was not committed to libraries. This week, the county kicked off a $22 million renovation project in Woodlawn. The Essex and Landsdowne libraries are in the renovation pipeline and major improvements already have come to branches in Catonsville, Pikesville and White Marsh.

Klausmeier added that the Essex and White Marsh libraries are only five miles from Middle River, and the Perry Hall library is only six miles away.

A new county executive will be elected in 2026. Three of Marks’ council colleagues are running. He hopes the developer will come back to the table if a new county executive is willing to negotiate.