AUBURN – The company has been as discreet as the block-letter logo stamped on the bottom of the blueprints stashed in the Twin Cities’ planning departments.

For 26 years, Technical Services Inc. has prepared site plans for most of the major developments within Lewiston and Auburn, whether retail, industrial or residential. Now that logo will change as owner Michael Gotto announced Thursday that TSI is being sold to Sebago Technics, a Westbrook-based engineering company.

“They approached me, and it got me thinking that some day, I might like to retire,” Gotto said with a laugh. TSI offers surveying, land use and civil engineering services.

The motivation for the acquisition was clear, according to Mark Adams, executive vice president of Sebago Technics and a former planner for both Twin Cities. “This is the second most active market in the state,” Adams said. “In terms of growth and momentum, it could be No. 1.”

The move instantly gives Sebago Technics a greater presence in the L-A market, and the connections that Gotto has built over two decades in the business. Clients include developers Gendron & Gendron and George Schott, as well as dozens of smaller developers in the area.

They, too, will benefit from the acquisition, Gotto said. Sebago Technics offers specialized services such as geotechnical engineering and traffic engineering that is beyond TSI’s scope. Clients who need the additional specialty services will be able to get them in-house, saving time.

“Everybody wants to move fast,” Gotto said. “Now we’ll be able to move projects quicker, plus you get the additional strength and knowledge of their staff.”

The deal should close on Jan. 1; the purchase price was not disclosed. Adams said the 10 TSI employees will be asked to stay on with Gotto leading the Center Street-based team.

It’s likely, however, that the office will move to a bigger location sometime in 2007, since Sebago Technics plans to add to its 80-person staff and expand the L-A-based operation.

That’s welcome news to Gotto, who has been working seven days a week for more than the past four years.

“It’s been extremely busy,” he said. “And I don’t see it letting up here.”

Among the projects: the Wal-Mart Distribution Center, the stores in the Mt. Auburn Avenue area, warehouse and manufacturing facilities in industrial parks.

“There’s been some serious ground work done by the cities, putting them in a position to attract commercial development,” he said.

Mark Adams agrees, and cites it as one of the reasons Sebago Technics made the offer.

“We want to be part of that,” he said.

Sebago Technics typically handles 500-600 jobs per year across the state, but the bulk are within a 100-mile radius of Portland. TSI handles between 100 and 150 projects a year, mostly in the L-A and western Maine area.

“It’s very exciting for us,” Adams said. “We’ve been looking to break into this market in a bigger way.”