Traffic could be the single most challenging issue facing the Elementary School Building Committee, with members acknowledging the need for more detailed analysis and communication with the public.

At Tuesday’s meeting, the committee reviewed the various possible design options for Elmwood School either on Elm Street or Hayden Rowe Street.

The sites are designated as “Elmwood Bar,” “Elmwood Village,” Hayden Rowe Pinwheel” and “Hayden Rowe Village,” with different designs marked east and west depicting either Grades 2-3 or Grades 2-3-4 options.

Vertex Project Director Jeffrey D’Amico explained the committee would look at half of the evaluation criteria on Tuesday and the second half at its meeting next Tuesday at 6 p.m.

D’Amico highlighted a color-coded matrix that rated the design options in specific areas.

The codes included red for least advantageous, orange for less advantageous, yellow for neutral, light green for advantageous and dark green as more advantageous.

D’Amico said police and fire personnel were comfortable with all the options and had no issues should a new school be built with three stories. He noted that once a site/design is chosen, those personnel would review floor plans and voice their concerns.

Most of the conversation involved the traffic and district operations categories, including busing and maintenance.

Director of Finance Susan Rothermich said there could be a reduction in the number of buses if Hayden Rowe is chosen as the site. She said that selection could eliminate 15 minutes of cross-town trips to pick up from another school and shorter bus rides for students.

Director of Facilities Tim Persson said it would be more efficient for snow plowing and other maintenance tasks to have a new Elmwood School in closer proximity with the Marathon School rather than having to cross town to pick up equipment.

Board members talked about how the design for Hayden Rowe seeks to pull traffic off the road and have it queue and circulate on-site. However, ESBC chair Jon Graziano noted there still would be more cars on Hayden Rowe Street because of the crossover of kids.

Members tried to determine if it should be rated “neutral” or “less advantageous” ultimately, as it was coded orange on the chart.

School Committee member Jenn Devlin said she saw potential for the traffic to be improved if “a chunk of it is pulled off the street.”

School Committee member Lya Batlle-Rafferty added that they didn’t really know what it would be like when all was said and done.

Graziano said the amount of data that is needed on traffic would be a lot more than what is typically done on an average project. Communication with the public needs to be comprehensive, he said. Answers are required for questions on timing of buses, the number of people dropping off and picking up students, what the town can do to calm down traffic near all the schools and much more.

“It would be easier if this project was in a vacuum and it isn’t from a cost perspective and from traffic if we go to Hayden Rowe,” Graziano said.

Some members were in favor of classifying the traffic impact as “neutral,” which the chair said would be a bad move.

“If we make it yellow, most of the public is not going to believe us,” he said. “We have work to do to tell this story.”

Building Committee member Michael Shepard noted he said from the beginning of the process that traffic would even supersede costs as the main sticking point with townspeople.

He said there is an opportunity for the public to come out when the project goes to the Planning Board. When it gets to Town Meeting for a funding vote, Shepard said, there could be a “pissing match.”

“This guy we hired to do the traffic [study] has got to do his damn job in order to make this work,” Shepard said.

Graziano asked that the discussion on traffic continue at the next meeting and the consultant be brought in after first being briefed on the scope of all he must look at and the considerations he has to take into account to come up with accurate analyses.

Batlle-Rafferty said that like with the budget process, people want to see transparency over time, that the committee is taking it seriously and there is movement forward on the traffic analysis.

“If they can see what’s happening, that will be a huge positive,” she said.

In other categories, both sites initially were deemed neutral for walkability and bike-ability. Following discussion about safety and the ages of children possibly walking if grade changes are made, the Elmwood locations were dropped to less advantageous and Hayden Rowe remained neutral.

For criteria concerning site complexities, D’Amico said while both locations have wetlands that need further study, there is more ledge at Elmwood, and blasting it near an existing building is of concern, he said.

He explained that big rocks can be drilled, separated and crushed, while ledge requires drilling and blasting in a controlled environment. Additionally, abutters of 250 feet have to be notified in the latter situation.

However, D’Amico added that a project in Ashland has had this blasting done with no problems near an existing building.