A New York company has finalized its purchase of an Old Town engineering and natural resource consulting company.

Treadwell Franklin Infrastructure, a project development and finance company, bought the James W. Sewall Company, which was started 138 years ago. The company will operate out of Sewall’s Portland and Old Town offices, Proposal and Communications Manager Diane Vatne said.

The two companies have worked together on project planning since 2015.

Vatne said that last year “Treadwell Franklin, being a good partner and it seeming very symbiotic, started to get the idea of purchasing Sewall.”

The Sewall Company has worked on numerous projects throughout Maine over the years, from commercial developments along Bangor’s Stillwater Avenue to creating digital maps for towns including Houlton.

Sewall offers engineering and geospatial services as well as broadband and telecom consulting and planning, land appraisal, survey and mapping. Treadwell Franklin, founded in 2015, develops and oversees installation of large-scale infrastructure, including transportation projects, industrial centers and municipal and educational campuses.

“Why Sewall is so important is it gives us depth to oversee projects,” said Brewer native and newly named Sewall President George Campbell, who is Treadwell Franklin’s former advisory board chairman.

“It gives us depth to oversee projects. I think even more importantly, it gives us the ability to assess the efficacy of a project,” he said. “They have the strength of service that we need, and yet because of their size, they can be very nimble.”

Eventually Treadwell Franklin intends to separate Sewall’s forestry practice into a separate subsidiary, according to a press release.

The purchase was completed May 1. Sewall employs about 60 people in offices in Old Town, Portland, Caribou, Gardiner, as well as in Minnesota and Georgia.

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