The preferred site of a new southern-Suffolk elementary school is not appropriate for a school, the city’s Planning Commission ruled on Tuesday.

A site proposed for the school that would replace Robertson and Southwestern elementary schools does not fit within the city’s comprehensive plan, commissioners said.

The decision on the site, located at 1553 Copeland Road, now will be forwarded to City Council. That body either can uphold the Planning Commission’s decision or overturn it with a majority vote.

The proposed location was chosen by the School Board from among more than a dozen sites. It is located near Copeland Road’s intersection with Jackson Road.

Planning staff had to consider whether the site is consistent with the city’s 2026 Comprehensive Plan, and came to the conclusion it is not, said Planning Director Scott Mills.

The Comprehensive Plan guides against placing large schools in the Rural Conservation Agricultural District, and instead recommends that schools be placed either in the Urban/Suburban Growth Districts — greater downtown and North Suffolk — or in the villages.

However, the proposed replacement school would draw students from the western and southern parts of the city, as well as from areas of downtown. Putting the school in the village of Holland, the village of Whaleyville or in downtown would create inordinately long bus rides for elementary school students from the other two areas, school officials have said. The City Council voted last month to defer the construction of the new school to the 2011-2012 fiscal year.

Commissioner Ronnie Rountree supported the site, but agreed it is not consistent with the comprehensive plan as written.

“We have told them we would like to see one school try to be centrally located,” Rountree said. “I see this as centrally located for our students as you probably could possibly get.”

School Board member Phyllis Byrum, who represents the Whaleyville Borough, said none of the sites the board has considered are in a village or in the downtown area, because the school should be centrally located to all the students it will serve.

Building two schools would not be economically feasible, said James Thorsen, executive director of facilities and planning for Suffolk Public Schools.

“The most expensive schools you will ever build will be small schools,” Thorsen said, noting that small schools also are more expensive to operate.

Other commissioners acknowledged they could not support the Copeland Road site with the comprehensive plan as it is written.

“Unless City Council wants to amend the comprehensive plan, I can’t endorse this,” said Commissioner Arthur Singleton.

Planning Commissioner William Goodman noted that other schools adjacent to agricultural areas, such as Florence Bowser Elementary School, have suffered problems with their location.

“Florence Bowser is a big river when we get a lot of rain,” Goodman said. “I can’t support this particular site.”

Goodman also cautioned that going against the comprehensive plan would set a bad precedent, while other commissioners expressed concerns with the actual site, such as the availability of water and sewer service and the safety of travel on Copeland Road.

The Commission voted 7-0 to recommend denial of the site because it is inconsistent with the comprehensive plan. City Council will take up the issue at a later meeting.