New London ― More than two dozen contractors hoping to take part in the construction of the National U.S. Coast Guard Museum attended a “robust” bid opening event earlier this month, museum association leaders said Monday.

“We had contractors there representing nine trades, including those specializing in subterranean work and steel, along with those that provide emergency generators for these types of buildings,” said Wes Pulver, association president and a retired Coast Guard captain. “Those companies represented about 50% of the overall construction work we plan.”

Pulver said 70% of the project’s anticipated $150 million price tag ― which includes the creation of a pedestrian bridge projected to connect the downtown museum to the Water Street garage and building finishing work ― will be dedicated to construction of the main museum building.

The April 3 bid opening at the Garde Arts Center will now be followed by a second submission round on April 17 in which a small number of contractors – mainly those who handle wall-related work ― are slated to submit their bids, Pulver said.

Bids for construction of the 89,000-square-foot, six-story museum building and its associated interior systems were requested in late February by North Stonington-based A/Z Corp., which is overseeing the work.

The scope of the work at 1790 Waterfront Drive includes concrete foundation, skeletal steel and flooring, as well as exterior metal panel, glass curtain wall and roofing components. Companies are also invited to bid on elevator, fireproofing, plumbing and electrical work.

The project is being handled through a phased construction approach that began with site preparation behind Union Station about 20 months ago and is continuing with the installation of roughly 240 micropiles on which the museum will sit.

Bids for construction of the main museum building are expected to be awarded within 90 days, Pulver said. He said the association is holding off on releasing prospective bid figures for now.

“We want to make sure the bidders understand the full scope of the project first,” he said. “But those numbers are coming in similar to our cost estimates.”

The project is being funded through a combination of federal, state and donated funds. Approximately 6,000 donors so far have contributed $46 million in private money toward a $50 million capital campaign.

The walking bridge and interior museum finishing work portions of the project will be bid out separately later this year in the hopes of awarding those contracts by early summer.

A project timeline calls for the museum building to be completed in 2025 before being turned over to Coast Guard officials who will set an official opening date.

The bridge will likely not be completed until 2026.

Museum boosters, including city officials, are touting the facility as a tourism generator estimated to bring 300,000 annual visitors to the region along with up to $20 million in associated tourism revenue.

j.penney@theday.com