A wetlands appeal could add $17.6 million to the Lexington High School rebuild, according to town committee estimates cited in a resident's letter.

Todd Rhodes, a Lexington resident, laid out the figures in a Wednesday, Sept. 2 letter to The Lexington Observer, drawing on a presentation from the Permanent Building Committee's (PBC) Wednesday, Aug. 19 meeting. The estimates show escalating costs depending on when the Massachusetts Department of Environmental Protection (MassDEP) rules on a residents' appeal that has frozen construction on the $659.7 million project.

If MassDEP had decided by Tuesday, Sept. 1, the added cost would have been $1 million to $2.5 million, and students would still move in on schedule in September 2029. A decision by Oct. 1 would add $2.5 million to $5 million, with the 2029 move-in still possible "with hard work and some luck." A decision delayed to Nov. 1 would add $17.6 million, force both the old and new buildings to operate at once, require the town to buy furnishings and IT equipment rather than reuse them, and delay field construction by a year.

Tuesday, Sept. 1 has passed with no ruling.

At an earlier School Building Committee meeting on Monday, Aug. 17, director of public facilities Mike Cronin estimated the worst-case cost at over $12 million, The Lexington Observer reported Aug. 20. The $17.6 million figure from the PBC's Aug. 19 presentation represents a significant jump from that estimate. Turner Construction executive Jamie Meiser told the same Aug. 17 meeting that the project team cannot conduct any site work on the wetlands or within 100 feet of them until MassDEP decides, the Observer reported.

MassDEP representative Jill Provencal said after a Thursday, Aug. 27 site walkthrough that the fastest possible review would be two weeks, but that the project is large and the process could take "potentially much longer." She said she would not decide until she had all the information she needed. No deadline has been announced.

About 100 people attended that Aug. 27 walkthrough, roughly a third wearing "Yes for Lexington" pins supporting the current design, the Observer reported. "This was the biggest group I've had in my career," Provencal said at the end of the tour.

The appeal, filed by resident Jim Williams and signed by 12 Lexington residents, argues the School Building Committee did not adequately consider alternatives to building on wetlands as required by state law. Williams, who described himself as an "environmental extremist" to the Observer after the walkthrough, has attended LHS project meetings for years to voice concerns about the design's impact on on-site wetlands.

The project's design, nicknamed "Bloom," was selected after the committee reviewed 299 vacant parcels and 19 building designs. It has been approved by the Select Board, Town Meeting, the state legislature, the Massachusetts School Building Authority, and the Lexington Conservation Commission. Voters backed the debt exclusion to fund it in December 2025 with about 62 percent support.

Town Manager Steve Bartha said MassDEP's response is "standard for these appeals" and that "a very small minority of these appeals result in making changes" to local conservation commission decisions, the Observer reported in August.

Rhodes' letter urged the appellants to withdraw. "They now have the opportunity to save the town millions of dollars by rescinding their appeal," he wrote. No public response from Williams or the other signers was available as of Friday, Sept. 4.

MassDEP's next step is to decide whether to issue a Superseding Order of Conditions, which could affirm, modify, or add to the Conservation Commission's original conditions and could require changes to the school's design.