Upholding a controversial decision by the city’s Historic District Commission, the Covington City Council voted 4-3 Tuesday night to grant permission to St. Scholastica, a 650-student Catholic girls school on the edge of the city’s historic district, to build a new gym and multipurpose building on campus.

The decision came after sometimes emotional speeches by members of the public and the council during a debate that lasted nearly three hours.

The four members who voted to uphold the decision were Mark Wright, Larry Rolling, John Callahan and Jerry Coner, despite a last-minute effort by Callahan to table the issue.

Voting to reject the plan were Rick Smith, whose district includes the site, plus Lee Alexius and Sam O’Keefe.

Proponents stressed their position that the current gym — which seats about 600 — is too small to hold the entire student body for masses, assemblies and sporting events.

The plan before the council was the second one the school prepared. In response to public opposition, the school’s architects revised the original plan to move the gym farther from Jahncke Avenue and to add a vegetation-covered “green wall” to help break up the building’s monolithic appearance.

Opponents countered by saying the proposed building — 56,000 square feet across two stories — would be out of scale with surrounding small homes and would amount to a big box in a residential area. Others decried the fact that the plan would require the removal of two live oak trees.

Many of the opponents went out of their way to enumerate their own or their families’ connections to St. Scholastica, including wives, daughters, nieces or friends who attended the school.

Lisa Condrey Ward, who owns the Southern Hotel, a revived century-old hotel set to open in the next few weeks, spoke against the proposal.

“What you see as you drive down an iconic avenue in the heart of a historic neighborhood is the backside of a box,” she said. “There’s no rhythm,” she added, using one of the enumerated criteria the council was supposed to evaluate, along with the building’s scale, texture and materials.

She acknowledged that the academy needs a new facility — just not this one.

“I want them to get a better campus. But there are other ways to do it that follow the rules. It’s a slippery slope,” Ward said.

Paul Mayronne, a Covington lawyer, asked what rules the school was supposed to follow.

“If this is denied, the question would be: What are we supposed to build there?” he asked. “We looked at the criteria and that’s what we did.”

Tuesday’s debate revealed that some residents had been preparing for the meeting for some time.

Kate and Mike Gilley, who oppose the project, presented the council with a tabletop model complete with twigs to represent the trees on the site.

Council members asked project architect Michael Holley if the model appeared to be to scale.

Holley said he could not really say, but he objected to the fact that the model’s buildings were black boxes and had no detail.

Many opponents said allowing the gym to be built would open up the city to similar projects by other groups.

“This will open a Pandora’s box; surely there will be more and more requests,” said Pat Clanton, who expressed her opposition in a shaky voice.

The debate has been so heated that two councilmen bemoaned the way it had degenerated. “It’s tearing us apart,” said Smith.

Supporters contended there is little in historic Covington that has been there longer than St. Scholastica, which opened in 1903.

Tuesday’s hearing before the council was called after the five-member Historic District Commission unanimously approved the project last month. But a group of residents appealed the decision, which sent it to the council.

The expected turnout was so large that the meeting was moved from the council chamber to the School Board’s meeting room, which has double the seating capacity.

The school must now take its plan before the city’s Planning and Zoning Board.

“This is not over,” Rolling said.

Follow Faimon A. Roberts III on Twitter, @faimon.