LEWISTON — Lewiston’s new elementary school that was to open in 2018 may open a year later, in the fall of 2019, Superintendent Bill Webster said Thursday.

The delay stems from finding the right site to build the school that would accommodate Martel and Longley elementary students, plus others. As planned, the school would be built in or near the Martel and Longley school neighborhoods.

“This whole process has taken longer than expected,” Webster said. “We do have it narrowed down to a few sites.”

The sites cannot be named publicly because that would hurt land purchase negotiations, Webster said. An executive session is scheduled July 7 between the School Committee and the City Council to get city input before negotiations with landowners, Webster said.

What School Committee members now need to know from city officials is whether the city would pay more than the appraised value of properties, and whether the city would pay for more acres than the state would cover, Webster said.

“Once we get feedback from the council and School Committee, we’ll be talking to the appropriate landowners,” Webster said.

Before the sites were narrowed to a few finalists, the School Department considered 16 sites. Several landowners have offered to donate land for the school, Webster said. “Those sites may not work out, but it’s gratifying to see their interest.”

He hopes to announce a site later this summer. Once one is chosen, Lewiston residents will vote in a nonbinding straw poll. Following that, approval will be needed from the State Board of Education.

“I’d love to have approval this fall,” Webster said. “There are a lot of things to be put in place,” including the design of the school. “The design is very site-specific.”

According to state regulations, the site for an 800- to 900-student school should be about 29 acres. In other districts, schools of that size have been built on 15 acres, Webster said.

“We’ll see how this all shakes out,” he said.

Lewiston has won state funding for the construction, which means local property taxpayers would pay about 5 percent of the new school, the state 95 percent. Typically, an elementary school of that size would cost about $40 million.

The school’s expected enrollment is far less than 1,200 students officials thought would be necessary last year. The higher number was based on the School Department’s internal forecast. “We brought in an outside consultant who said enrollment has peaked at the elementary level and will slowly taper off,” Webster said.

He said he’s concerned about the accuracy of that projection. When the last two schools opened — Farwell in 2007 and Geiger in 2010 — both were full on opening day despite enrollment studies.

And, “we get reports from the city about people moving into Lewiston. Those numbers continue to grow,” Webster said. “I’m going to be very interested where it’s going to be.’

Spring registrations show that kindergarten classrooms will meet the 20-1 student-teacher ratio. Webster said he’s concerned that more registrations “will come out of the woodwork in August, almost until the first day of school.”

There are 450 registered kindergarten students. In some years, as many as 50 new kindergarten registrations came at the last minute, Webster said.

Martel and Longley each has 350 students, far more than the buildings were designed for. Another 100 students live in the Martel and Longley neighborhoods but attend other schools.

Counting those students, the new school population would be 800, plus students from other crowded schools.

Lewiston voters will have the final say on approving a new school in a referendum, which could be held in 2016.

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