Bridgewater Associates won quick approval from the Planning and Zoning Commission Thursday night to expand and renovate parts of its Glendinning campus.

Site plans and a special permit to modify the hedge fund’s office compound at 1 Glendinning Place and 25 Ford Road were unanimously approved with no debate by the commission or comment from the public.

“I think we’ve been very lucky for this town to have an owner to come forth with such a green and intelligent plan,” P&Z Chairman Skip Stephens said.

An additional 22,000 square feet of space is planned on Bridgewater’s 21.7-acre site, including a two-story addition to one building. Plans also call for constructing an underground parking garage, which will ultimately increase total on-campus parking capacity from 250 spaces to 341.

The current Bridgewater complex, which includes a 100-year-old mill off Ford Road that was converted to office space years ago, now encompasses 60,734 square feet.

“The size of the buildings are fundamentally remaining the same,” said architect Jim Cutler of the Washington State-based firm Cutler Anderson Architects. “The amount of use will fundamentally remain the same.”

Last year, the P&Z paved the way for the project when it passed an amendment to allow increased coverage in a Design Development District zone, which imposed strict limits on the size of corporate development.

Some redesign work with the entryway off Weston Road is designed to facilitate having more employees enter the property via Weston Road (Route 57), versus from Ford Road. According to Mark Vertucci, a traffic engineer with Fuss & O’Neill, there will be about 60 more people arriving each day from Weston Road.

“You will have some more left turns turning into that driveway than you do today,” he said.

“It just seems that there’s a lot of capacity for congestion,” noted P&Z Commissioner Andra Vebell. “That’s a major focal point in traffic.”

“The road is about 16 and a half feet wide in the northbound direction today …” Vertucci said. “Most vehicles would be able to squeeze by on the right side, (but) the DOT will be looking at that and if they want us to add another foot or two on the outside, that’ll be part of the process.”

While a number of trees will be cut down along Ford Road, and requests have been filed with the tree warden for approval of their removal, the modern design of the new septic system will allow an irrigation area within the forested section to the north of the property without having to clear any land, planners said.

“The proposed septic is really going to be hand-dug, so you’re not going to get big machines in there,” said Eric Bernheim, the lawyer representing the applicant.

“I think this is a great project,” he said. “It’s great for the site and it’s great for the town of Westport.”

The headquarters of Bridgewater Associates, the world's largest hedge fund, has been located in town for the past 17 years. It had announced plans last year to move its corporate offices to Stamford. Despite $115 million in state incentives for the firm to move to a new waterfront headquarters in that city, the project became mired in local zoning disputes and Bridgewater ultimately pulled out.

However, to accommodate the renovations on its Glendinning campus, Bridgewater does plan to temporarily relocate several hundred workers to Stamford.

The hedge fund plans to lease more than 100,000 square feet of space in one of the office buildings at the waterfront development owned by Building and Land Technology. The 14-acre peninsula where the firm had originally planned to build its new headquarters remains vacant.

Bridgewater Associates was the town's fourth largest taxpayer on the 2014 grand list, with holdings assessed at $22,053,470.