East Lyme — Worries that ongoing Costco-related roadwork at the Interstate 95 Exit 74 interchange will extend through September have prompted a Department of Transportation project engineer to schedule an "all-hands-on-deck meeting" Monday with the town, Costco developers and DOT.

Brent Church, the engineer responsible for ensuring roadwork in the Exit 74 Interchange area is being carried out properly, said by phone Thursday that communication among the town, DOT and Costco developers has been inadequate since the roadwork began earlier this summer. Drivers traveling through the area have experienced significant delays in recent weeks, with Church concerned that the project will continue on as the school year approaches and as a Route 1-Boston Post Road bridge replacement begins.

“The communication between the developer and the town needs to be much clearer, and there needs to be constant communication going across the board on a daily basis,” Church said. He said he was forced to shut down “Costco’s entire operation” Wednesday because southbound vehicles trying to get off I-95 had to stop on the Exit 74 off-ramp due to the construction. The backed-up traffic extended all the way onto the highway, which is two lanes wide there. “These projects are very difficult and this is a very difficult area to do work in. It’s the summer crowd, there’s a lot of people moving through that area. So we have to do what’s right for the town and the people that live there.”

Church said Thursday that he doesn’t believe Costco work will be finished until early October “at best.” He said that’s because Costco developers have not yet submitted final “signalization plans” outlining how and when they will install signal lights to control traffic traveling along the exit’s southbound off-ramp.

According to Costco’s plans, the southbound on-ramp and off-ramp will be extended into a T configuration on a frontage road running by Pools Etc., allowing drivers coming off the interstate to either turn left toward Costco or right toward Route 161 after a stop light. The northbound on-ramp entrance also is being altered.

As part of the work, Church said that the exit’s northbound on-ramp will need to be closed for 14 to 16 hours over a night in coming weeks to finish its reconfiguration, while the southbound ramps will need to be closed for three to four days. Church said those closure times have not yet been scheduled because of planning delays on Costco's end, stalling the entire project through September.

“This needs to legitimately be straightened out before the schools start their bus schedules,” he said. “It needs to be clear that the town is responsible for getting on top of the developer, who should be getting on top of his engineering and inspection firm out there to de-stem this congestion. It is up to the town, its police force and the developer to coordinate to keep traffic flowing safely along Route 161, while I'm responsible for the interchange and the highway.”

The ongoing Exit 74 work comes as Costco plans to open its East Lyme store in the coming months and is not part of a more extensive Route 161 widening and Exit 74 bridge replacement project being planned by DOT. Construction for that project is anticipated to begin in summer or fall 2021, and is expected to last approximately three to four years, DOT spokesman Kevin Nursick said by email last month.

Costco developer Newton Brainard, vice president of development and acquisition for The Simon Konover Co. of West Hartford, which is developing the Costco site with KGI Properties of Providence, was not immediately available by phone for comment by Thursday’s deadline.

Public Works Director Joe Bragaw said Thursday that Costco developers haven’t been updating the Public Works Department on a regular basis and until now, he thought they were running on time to finish roadwork by September.

“I think we have to wait for Monday’s meetings to know for sure what is happening,” Bragaw said. “I think it’s too early to say anything, and once we hear from the developer, we will know more about where we are.”

m.biekert@theday.com