In a 6 to 1 vote, the School Committee on Wednesday night signed off on a sweeping overhaul of the Boston school system’s assignment process. Current students in the system of 57,000, along with their siblings, are grandfathered under the existing 3-zone plan, which has been in place for 24 years.

The new school assignment system, which will go into effect in 2014, deep-sixes the zones, and relies on several factors, including an algorithm, to determine where a child will go to school. Known as the “home-based” plan, it offers a minimum of six schools, including the closest top-tier, schools, 2 top or second-tier schools and 2 schools from the first, second or third tier, according to the school department.

The plan also eliminates the walk zone “priority” for parents. The school department says parents will retain walk zone access – choosing a school within a mile from their home – under the “home-based” plan.

The plan drew an immediate condemnation from City Councillor At-Large John Connolly, a mayoral candidate and chair of the City Council’s Education Committee. He said the plan has “deep flaws.”

An advisory panel – put together by Mayor Thomas Menino and made up of parents and academics, along with education experts – overwhelmingly voted for the “home-based” model on Feb. 25.

“A more predictable and equitable student assignment system that emphasizes quality and keeps our children close to home has been a long time coming for our city,” Menino said in a statement shortly after Wednesday night’s vote. “Boston Public Schools have never been stronger – and now is the time to ensure our student assignment process reflects the great progress we’ve made.”

Menino met with elected officials of color at City Hall earlier this week, who had pressed for the elimination of walk zone priority. The meeting included Superintendent Carol Johnson, and state Sen. Sonia Chang-Diaz and state Rep. Carlos Henriquez, among others.

School Committee member John Barros was the lone vote against the plan on Wednesday. He was forced to withdraw an amendment that would have added the number of available seats into the school assignment equation.

After the vote, he told his colleagues he supports the “home-based” model. “I voted no because I couldn’t have a conversation,” Barros said, a reference to the school department’s legal counsel frowning on possible changes to a proposal brought by Superintendent Johnson, while the motion to approve it was on the table.

In an email to supporters on Thursday morning, Connolly blasted the School Committee and the administration, and called the process a “lost opportunity.” “They did not guarantee school quality and they replaced the current convoluted school lottery with a different convoluted school lottery,” he wrote.

The elimination of the walk zone priority “hurts the 80% of families across every neighborhood that make a school in their walk zone one of their top choices,” he added.

But members of the 27-member advisory committee, which had recommended waiting on making a move on walk zone priority for two years, defended the elimination. “Walk zone priority under the new plan doesn’t accomplish much at all,” because the walk zone access would still exist as part of the algorithm, according to John Nucci, a former city councillor and a member of the advisory panel.

Dean Hardin Coleman, co-chair of the panel, said keeping walk zone priority could be seen as “double-dipping,” layering on two geographic advantages on top of one another. Menino and Superintendent Johnson felt it was an “unnecessary element” in the plan, he added.

But some parents, like Sarah Heffernan, a parent involved with the Everett Elementary School in Dorchester, said they wanted walk zone priority as a fail-safe to ensure they will have seats at a school close to home and a chance to build a community around the school.

In her letter to the School Committee, Johnson, who took a leave after the death of her husband on Monday, asked the School Committee to reach out to parents about their experiences with the new model. “This represents a major step forward for our city,” she wrote.

“Your approval tonight will allow us to focus together on improving quality and access to quality all across our city,” she added. “This is the most important work.”