The Portland Board of Education voted unanimously Tuesday to authorize the superintendent to enter into negotiations with a project architect for the renovation of three elementary schools.

Harriman Associates, which also designed the renovations for a fourth school currently underway, was chosen over three other firms that submitted proposals for the renovations of Longfellow, Presumpscot and Reiche elementary schools.

The four school renovations, known collectively as the Buildings for Our Future project, will be paid for with a $64.4 million bond authorized by voters in November 2017.

The cost of the design contract with Harriman will be part of negotiations, according to board documents. Once the contract is negotiated the district will move ahead with developing a timeline for the projects, Superintendent Xavier Botana said.

The other firms who submitted proposals were: Lavallee/Brensinger Architects, Oak Point Associates and PDT Architects.

During the meeting, Botana also addressed a significant drop in enrollment for the coming school year at Deering High School, which in recent years has enrolled a freshman class of around 220 students but this year has just 127.

The enrollment drop comes at the same time Portland High School has seen a spike in its freshman class numbers.

Some members of the school community contacted for an article in the Press Herald attributed the shift to a handful of incidents last fall that generated concerns about the school climate.

“As myself and other administrators acknowledged in the article, we are concerned with the conditions that led to this enrollment shift and we will be working to put in place structures to prevent that from happening again,” Botana said.

He also said Deering is one of the most diverse high schools in New England and has had successes not mentioned in the article including expanding Advanced Placement programming and student achievements in the arts and athletics.

There was no public comment on the issue or comment from board members.