Groton — When Ella T. Grasso Technical High School students returned for classes, they were met with a sprawling expanse of fenced-off construction.

But Principal Patricia Feeney said with a laugh that with a lot of planning, the transition has "been really smooth."

She met over the summer with construction manager O&G Industries to plan new bus routes, parent drop-off/pick-up and restructured parking.

"We're trying to make sure everybody's safe," Feeney said.

In June, shortly after school let out, O&G Industries began construction of a new 220,000-square-foot school. The roughly $135 million facility, which includes $98.3 million in construction, is state-funded through bonds.

O&G Industries was hard at work over the summer preparing the ground for construction.

"They had to come in and literally tear up trees and actually dig to get to the level that the school's going to be, take out boulders and then relocate gas lines," Feeney said. Crews also had to restructure fiber optics and electric lines.

With a 62-acre property, Grasso Tech is keeping its existing facility open while constructing the new building on-site. The construction site previously contained the driveway leading to the school, grassy areas and wooded areas, Feeney said.

She noted that the project to replace the current school, built in 1977, was approved in 2004 but was halted several times.

"The condition of our building right now is deteriorating rapidly," Feeney said. It has suffered issues with ventilation and HVAC.

While Grasso Tech has about 485 students now, the new school will be built for a capacity of 800, and Feeney is hoping for an initial increase of about 100 students.

The new building is expected to be open for students in the fall of 2019. It will feature the combination of the hospitality and culinary programs — with a restaurant — and a new welding program, to help meet the needs of Electric Boat and other area manufacturers.

Grasso Tech has refurbished an old welding shop for use by Electric Boat and Three Rivers Community College in the evenings, but there is no welding program for students.

"There's going to be enough space in the new building if we want to expand," Feeney said, "and we have talked about masonry and digital media but, when we open, that will not be part of the project."

The new building will include an auditorium, an asset the current one lacks, and Feeney hopes this will help take Chamber of Commerce meetings held at the school "to the next level."

After construction is finished, the current school will be demolished, and Grasso Tech plans to put a football field and track in its place. Feeney said the school's football team, which is part of a tri-operative with Norwich Tech and St. Bernard, played at East Lyme last year and is playing at Norwich Free Academy this year.

The designer of the new building is Moser Pilon Nelson Architects.

"We're hoping that the community sees this as a positive, and we're very community-driven and we're very connected, so we hope to even strengthen those connections in the new school," Feeney said. "We'll be able to do a lot more with the new school."

e.moser@theday.com