New London — At a pace of roughly 200 truckloads of rock and soil a day, the 7 acres of water separating the two piers at the State Pier facility is slowly being displaced.

Filling that space to create one larger pier area is part of one of the biggest construction projects in the city in recent history, helping to reshape an industrial waterfront site on the Thames River that was built more than a century ago.

State Pier in New London is a whirlwind of activity these days, host to dozens of construction workers operating cranes, excavators and dump trucks with the single purpose of completing the estimated $235 million project by next year.

Representatives from the construction and engineering firm Kiewit, construction manager of the project, provided a brief tour of the construction site on Thursday. Progress also can be tracked online at statepiernewlondon.com.

The modernization project is the result of the Connecticut Port Authority’s agreement with port operator Gateway Terminal and joint venture partners Ørsted and Eversource. The project includes widening the pier and a major update of infrastructure to create a facility with heavy-lift capacity to accommodate parts needed to construct offshore wind farms.

While Ørsted and Eversource are contributing more than $70 million toward the project and will lease the facility for 10 years, CPA officials are quick to point out that the updated facility will be better suited to host an array of cargo when not in use by the offshore wind industry.

State Pier is expected to be put to use by the beginning of next year. Ørsted and Eversource broke ground on a 12-turbine South Fork Wind project off the coast of Long Island on Feb. 14. The wind farm is expected to generate 132 megawatts, enough to power 70,000 homes, and be operational at the end of 2023.

It’s the smaller of several wind farm construction projects associated with New London’s State Pier, which is expected to be used for the assembly and delivery of components. A larger project, the 704 megawatt Revolution Wind, is being planned for waters off the Rhode Island Coast.

Connecticut Port Authority Executive Director John Henshaw said dredging started in earnest once the project obtained a federal permit from the U.S. Army Corps of Engineers in December.

Dredging of the silt and organic material from between the two piers, known individually as State Pier and Central Vermont Railroad Pier, was completed on Jan. 20. This was needed to create a stable footing for the 380,000 cubic yards of material needed to fill the more than 7 acres of space between the piers and create one large central wharf area.

During Thursday's tour, there was a constant stream of dump trucks depositing material that was being pushed into the water by bulldozers.

Officials say there are 25 trucks working on the site, each making an average of eight trips per day, or 200 total trips. Some of the material is taken from soil excavated from the property and stockpiled atop the CVRR Pier. Some dredge material also will be used.

The type of fill being hauled to the site is classified as “clean fill” and authorized for use by the federal permit from the Army Corps of Engineers. Officials say it is soil consistent with the physical and chemical criteria established by federal and state guidelines that mandate the material — mostly rock and soil — be devoid of any pollutants.

Waterford-based Kobyluck Sand & Gravel secured the contract for the major part of the fill operation.

Elsewhere, a demolition dust control mister was humming as excavators clawed and jackhammered into a portion of State Pier that is being demolished. Cranes are positioning and driving into the ground large pipe piles that range in diameter from between 30 and 42 inches. The piles are driven into the ground to create retaining walls, known as combi walls, at various places around the piers, including the delivery berth and receiving platform.

More dredging will occur after Oct. 1 in the turning basin area, where ships will maneuver around the pier.

Henshaw said he expects the fill activity to be completed by the end of the summer, when the material in the Central Wharf area will be compacted before a final surface is completed.

While there have been no major delays since the start of construction, there have been hiccups.

The state Department of Energy and Environmental Protection reports that since it issued a permit for work at State Pier in August, it has fielded several complaints — specifically about the dumping of snow and use of a turbidity curtain around the in-water construction area. Those complaints resulted in follow-ups from DEEP but did not require any further enforcement, a DEEP spokesperson said in an email on Friday.

On Jan. 2, a DEEP emergency response unit responded to a report of the release of hydraulic oil from a dredging machine. In response, absorbent booms and pads were deployed to soak up the oil in the river and the equipment was repaired, DEEP said. The case has since been closed.

On Feb. 4, Henshaw reported to the CPA board that a “trespasser,” later identified as port authority critic Kevin Blacker, “breached the site” and caused work to stop while state police responded. Henshaw called the incident the “the height of irresponsibility” and promised an arrest if another incident occurs.

Of the complaints filed with environmental officials, Henshaw said, often “the complaints don’t match the reality on the ground.” The CPA is in regular communication with DEEP and the Army Corps of Engineers about ongoing work, he said.

As for the timeline and cost of the project, Henshaw said challenges to the CPA’s permit applications helped delay the project. He acknowledged that the schedule is closely associated with the cost of the project.

“The dredging permits in-water took a little longer than anticipated. That was a challenge and one we have to overcome,” Henshaw said. “I think we’ve tried to be clear there are repercussions associated with the delays. However, we’re doing our best to try and mitigate those through savings where we can."

The final price of the project still is being negotiated and is expected to be announced in the coming weeks. Henshaw said it's likely the CPA will work on an amendment to the contract with Kiewit prior to the guaranteed maximum price being finalized.

“Ultimately, what we’re trying to do is the best with the budget we can,” Henshaw said.

He said he expects Ørsted and Eversource to begin using the State Pier site by Feb. 1, 2023, when some deliveries are expected. Some work on the pier is expected to continue through April 2023.

g.smith@theday.com