Baker's proposal also involved building a road system to serve the property using a possible $10 million federal earmark and $3.5 million in county funds redirected from another project, among other potential funding sources.
Commissioner William J. Wivell seconded Baker's motion, but commissioners John F. Barr, Kristin B. Aleshire and James F. Kercheval voted it down, 3-2.
Baker argued the site was the best deal for taxpayers. Other potential sites for the school are in a similar price range, but the Mount Aetna site offers the unique ability to recoup some of that money by selling remaining land to developers and using the proceeds for other capital projects or to reduce borrowing, he said.
"In order for me to support this budget, the capital side, this is going to have to be included in it," Baker said. "My obligation's to the taxpayer."
Wivell agreed, saying his previous opposition to pressing forward with road projects in that area stemmed from a desire to finalize the purchase decision first.
He said that in earlier closed-session discussions, a majority of commissioners at one point supported buying the land for the school, but one had changed his mind.
Wivell said the location between the medical campus and HCC would be ideal for a high school with a science-related magnet program, and he also stressed the sale of land to developers would help fund the costly road system needed.
"We're talking about $20 (million) to $30 million in road networks that's going to be required here," Wivell said. "If the county doesn't acquire the property, we have no means of recovering that investment other than some ... special taxing district, something like that," which he said could discourage development.
Barr said putting a high school on the Mount Aetna Farms land would reduce its economic development potential as a site for biotech or other research companies, which he said would provide good jobs and generate real estate tax revenue for the county.
Aleshire said he didn't think a school site decision should be made without more input from the Washington County Board of Education and City of Hagerstown or without an upfront discussion with the Boonsboro and Smithsburg communities about how the site will affect redistricting decisions.
Reached by phone after the meeting, school board president Wayne D. Ridenour confirmed the Mount Aetna Farms land was one of four or five sites county and school board officials have looked into for an east city high school. He said he personally liked the site because of its potential for a STEM (science, technology, engineering and math) magnet program.
Ridenour said school system and county staff had been working together closely on finding a school site and, because the county is paying for the land, the final choice should be up to the commissioners.
Aleshire questioned whether much land would be left to sell to developers after excluding the school campus, road land and flood plain.
He said the county could still recoup money for roads from developers without getting in the middle of its sale.
Commissioner James F. Kercheval said he didn't want to commit to buying the land for a high school. However, he suggested redirecting money budgeted for school land acquisition and a Robinwood Drive widening project toward starting the roads projects in the Mount Aetna Farms area.
Getting those projects started is important to persuade federal lawmakers to support an earmark for a bridge over Antietam Creek needed as part of that road system, Kercheval has said.
The Robinwood Drive widening project is delayed because of land acquisition issues, and about $4.1 million budgeted for that project this fiscal year will remain unused for a year or two if not redirected, County Administrator Gregory B. Murray said.
Baker's proposal would have used about $3.5 million of that money toward the Mount Aetna Farms road infrastructure and added the rest to the county's $2.6 million school land acquisition budget to buy the property.
Aleshire said he wanted to reduce the amount of tax-supported borrowing in the budget, preferably by cutting the amount budgeted for school land acquisition, library renovations and repairs to Devil's Backbone Dam.
A motion by Aleshire to reduce budgeted borrowing from $12 million to $11.5 million and work out the details later died for lack of a second.