Spending on Concord’s new middle school could be capped at as high as $166.6 million or as low as $136.2 million depending on a range of decisions still to come, according to long-anticipated cost estimates presented at a meeting Thursday night.

The estimates are the first indication since the school district applied for state building aid in June 2022 with an estimate of $176 million of just how much the controversial middle school project could cost.

The school district’s architectural firm, HMFH Architects, Inc., presented two estimates – one at the lowest end and the other at the highest – and over the coming months, the firm will work with Concord’s school board and Middle School Building Committee to select what to include, with the final cost expected to fall somewhere between the two numbers.

The cheapest option excludes an auditorium and all but one field, for example, while the most expensive includes a 900-seat auditorium, multiple playing fields, and a track. The cheapest option would also be 6,000 square feet smaller than the most expensive.

How the cost of the project would impact residents’ property taxes depends on whether the project gets state building aid – which will not be known until next summer – and whether the school district dips into its facility trust fund. School board members have said they won’t decide whether to proceed with the project until they learn if the district will receive state building aid.

Without support from the state and money from the trust fund, the project would raise taxes $1.60 to $2.09 per $1,000 in home value in the first year, or $560 to $732 on a home worth $350,000, according to an estimate provided by school district Business Administrator Jack Dunn.

If the state contributes building aid and the district applies money from its trust fund, the project could raise taxes by $0.09 to $0.59 per $1,000 in home value in the first year, or $32 to $207 on a home worth $350,000.

Permutations of these funding options are also possible.

The middle school project has been in the works since 2016 and would not be completed until the summer of 2028 under the current timeline presented Thursday. A controversial school board vote last December to build the school at the Broken Ground site rather than rebuilding it in its current location has angered many residents. The rumored price tag for the project – based on the $176 million estimate in 2022 – has also worried people.

Some of the most consequential decisions about the project the board is facing include:

Auditorium: Whether to build an auditorium, and if so how big to make it. A 900-seat auditorium is projected to cost $6 million, a 600-seat auditorium is projected at $4.9 million, and a 400-seat auditorium is projected at $4.2 million.

Gymnasium: How large to make the gym. A 6,000-square-foot gym – smaller than the current gym at Rundlett – is projected at $1.2 million cheaper than a 9,000-square-foot gym.

Playing fields: How many playing fields to include. Both the most and least expensive estimates include a turf multi-use field ($1.38 million), but the most expensive estimate also includes a multi-use grass field ($769,000), a track and lawn field ($1.66 million), and a baseball and softball field ($1.06 million).

Exterior Ramp: An exterior ramp from the first to the second floor of the building is projected to cost $3.7 million.

Heating: A heating system that employs fully air-source heat pumps is $2.34 million cheaper than one than includes all ground-source heat pumps. A hybrid option lands in between.

Under the most expensive cost cap, the new middle school would be 211,296 square feet, a 28% percent increase from the size of Rundlett.

Following the presentation of the cost estimates and their potential tax implications, some board and building committee members expressed concern.

The highest tax increase presented is “untenable,” said board member Sarah Robinson. “That dog won’t hunt.”

“I’m also feeling nervous,” said Lisa Beaudoin, a disability advocate participating in the project. “I’m really thinking about everyone on a fixed income in this city. One of them is my son who – if the worst-case scenario comes to pass – the trustees of his special needs trust are going to ask me about selling the condo that is supposed to be his forever home.”

Rundlett teacher and building committee member Linda O’Rourke countered that a potential delay in the project also worried her.

“I can’t tell you how many times a day when I don’t have enough outlets in my room or my classroom is 92 degrees because that’s what the temperature hits,” said O’Rourke. “And I tell myself four more years, I can do this. That petrifies me that it may have to be more than four more years.”

Residents will have the opportunity to weigh in and ask questions about the estimates during community hearings on June 11 at 6 p.m. at the Mill Brook School and June 18 at 6 p.m. at the high school.

The school board is scheduled to vote on a price cap for the project on July 15, after which the architectural firm will spend about six months developing more detailed designs.

Jeremy Margolis can be contacted at jmargolis@cmonitor.com.