A fourth sinkhole has opened up as a result of construction on the Evergreen Line in Port Moody, and a major road in the city has been shut down.

Clarke Road is closed to traffic at Seaview Drive while crews work to repair the damage and assess the strength of the surrounding ground. No announcement has been made as to when the road will be reopened.

Businesses along the road say the ongoing construction has been hurting their bottom lines. Sadi Jalilian, who owns Melika Hair Salon on Clarke Road said she had 14 of 15 clients cancel their appointments on Saturday because of the road closure.

Next door, Hilltop Market owner John Yoo told CTV News he’s had to throw out perishable items like milk because of a lack of customers buying them before their expiration dates.

“In the last seven months, business has slowed down,” Yoo said. “I compared this year to last year. This year, by almost 20 per cent, is lower.”

Evergreen Line project director Amanda Farrell said construction in the area has taken longer than expected because of the “challenging ground conditions” underneath the roadway.

“We absolutely understand the frustration of the neighbours in this area,” she said. “It has been longer than we anticipated.”

Some local business owners say they would like monetary compensation for the business they’ve lost during construction.

Farrell said she couldn’t comment on whether that would be possible, but she said the managers of the project have regular meetings with the local community and would do everything they could to help.

Construction crews first noticed a dip in the pavement at roughly 6:30 Friday evening. The depression soon became a sinkhole four metres deep and three-to-four metres wide, Farrell said.

This latest sinkhole opened up when crews entered the tunnel boring machine chamber to change some of the machine’s equipment. When they did so, some of the ground outside the machine fell in, leaving an air pocket that caused the hole, Farrell said.

“The contractor did very extensive ground improvement work in front of the face to prevent that happening,” she said. “Unfortunately, there must have been a flaw in that ground improvement work and some of that material has come into the machine.”

The tunnel boring machine was also blamed for sinkholes that swallowed up ground along the Evergreen Line route in October, January, and April.

Eastbound traffic is being rerouted along Glenayre Drive and Mount Royal Drive, and westbound traffic is being rerouted down Cecile and Angela drives to Glenayre Drive.

The 11-kilometre Evergreen Line is an addition to the SkyTrain system that will connect the existing Lougheed Town Centre station to downtown Coquitlam. It is expected to open in 2016.