The Martha’s Vineyard Regional High School committee approved money this week to hire an engineer to take the next steps toward connecting the school to the town of Oak Bluffs’ wastewater treatment plant — a project estimated to cost the school $1.5 to $1.8 million.

Although the school committee will not officially give the green light to the project until the engineer verifies its viability, the money approved — $100,000 from the excess and deficiencies fund — will cover the engineering plans and the permitting from the Department of Environmental Protection.

The plan involves putting down more than two miles of pipe between the high school and Oak Bluffs’ treatment plant. It is the alternative solution to a plan in which the high school would build its own package treatment plant, which is estimated would cost $1.5 million.

The school’s wastewater plan is also expected to incorporate the yet-to-be-built YMCA building across the street, which was the catalyst for the regional high school project.

The high school is now at its capacity for its number of bathrooms and faucets. A bathroom is required by law in the building for the Rebecca Amos Institute, the school’s alternative learning program, but the school cannot add one.

“About a year ago, the Y and Martha’s Vineyard Commission brought together a group of people to talk about wastewater issues on the campus,” superintendent James H. Weiss said yesterday. “We’ve known we had a problem, but when it came front and center, we realized we need to do something.”

Three weeks ago, the Martha’s Vineyard Commission approved the 48,000-square-foot YMCA building to be constructed across the street from the regional high school, with the understanding that the YMCA would join the school in a joint wastewater treatment solution. The commission had reviewed the YMCA building as a development of regional impact (DRI).

At present, no agreement between the YMCA and the regional high school has been negotiated, but Mr. Weiss has kept the Y informed of the school’s plans.

“We are working this out on our time frame, not theirs,” Mr. Weiss said. “But if we can work that out so the timing works [for the YMCA too], that would be great.”

The wastewater committee voted unanimously last month to allow the regional high school to connect to the treatment plant, although the school is outside of the geographic area that the treatment plant is authorized to service.

The town of Oak Bluffs would benefit from the high school’s tie-in by gaining access to the school’s large leaching field for overflow during the summer, when school is closed and the town is at its peak water use. The town’s main leaching field at Ocean Park is nearly at capacity, so use of the school’s leaching field under the track would increase the town’s wastewater capacity.

The school’s leaching field is rated for 20,000 gallons of wastewater per day. The school is only allowed to use 8,000 gallons per day and typically uses only 4,000 to 5,000 gallons per day during the school year.

According to the superintendent, the school would have sole responsibility for paying for the installation of the pipes and pumps between the high school and the treatment plant. The school would then pay a metered charge for the number of gallons it used. Based on the number of gallons the school currently uses per day, that would probably cost the school an additional $25,000 to $30,000 per year, Mr. Weiss said.

“The cost [of tying in] is very similar to building a package treatment plant at the high school, but the advantage is the high school doesn’t have to go into the wastewater business,” Mr. Weiss told the land use subcommittee at their meeting on Monday, before the start of the regular school committee meeting. “Also, this keeps the neighbors happy,” he added.

Neighbors to the regional high school voiced opposition to a package plant early on. Further, school administrators, including Mr. Weiss and principal Margaret (Peg) Regan, have expressed reservations about running their own plant, which would require hiring a licensed wastewater treatment operator and could cost more annually than tying into Oak Bluffs’ treatment plant.

In April, Oak Bluffs voters turned down contributing any money toward a package plant that would service the high school, the future YMCA, Martha’s Vineyard Community Services, Island Elderly Housing and adjacent resident home site properties.

For the YMCA to tie into Oak Bluffs’ treatment plant, the organization would pay for the piping installation going from its facility to the high school across the street, Mr. Weiss said. Then the YMCA would incur a metered charge. Mr. Weiss estimated the YMCA will generate 1,300 to 1,500 gallons of wastewater per day.

The Martha’s Vineyard Commission’s written decision in favor of the YMCA project states that the YMCA would pay a share of the cost of construction and operation of the joint wastewater treatment solution equal to its share of the combined wastewater flow, or a minimum of 10 per cent.

Following the land use subcommittee meeting on Monday, Mr. Weiss informed the school committee of the subcommittee’s recommendation to approve using the $100,000 set aside for an engineer. The school committee approved the use of the money.

School committee member Roxanne Ackerman of Aquinnah questioned why the school would embark on a $1.5 to $1.8 million project to gain a bathroom or two, when enrollment is continuing to decrease.

The principal, Mrs. Regan, replied that the school should have additional wastewater capacity because it is the community’s go-to facility in case of an Islandwide emergency. In addition to needing a bathroom in the Rebecca Amos Institute, she noted that the school would also like to add a bathroom to the small building used by MVTV.

At the close of the subcommittee meeting, it was not clear whether the school would put the engineering work out to bid. Mr. Weiss had tentative plans to hire Schofield, Barbini and Hoehn in Vineyard Haven. But when he made it clear that whatever engineer designed the project should execute it as well, some subcommittee members suggested that Mr. Weiss first speak to the town of Oak Bluffs and the Martha’s Vineyard Hospital for their assessment of the company.