The historic Eads Bridge is now fit to carry MetroLink and motor traffic over the Mississippi River until at least the year 2091 with the completion of a four-year, $48 million rehabilitation project.

Modernizing the Victorian-era structure included sandblasting about nine coats of paint off the bridge’s ribbed arch spans and replacing about 1.2 million pounds of steel, said John Nations, president and CEO for Bi-State Development which co-owns the bridge with the city of St. Louis.

Extending the bridge’s lifespan also required sealing its cantilever steel structure with a protective coating, in addition to replacing track supports, track and rail ties, and patching masonry.

“When we originally started, we thought that it would extend the life of the bridge for at least 50 years,” said Nations, explaining that, during the project, crews discovered much of the bridge was still in exceptionally good condition.

Nations said working on the project, while continuing to run about 300 MetroLink trains across the bridge each day, presented major logistical challenges. In addition, work crews had to contain portions of the bridge while stripping paint and corroded metal for environmental purposes.

Credit Carolina Hidalgo | St. Louis Public Radio The public is invited to a celebration of the Eads Bridge on its top deck, starting Friday morning at 10 a.m.

The project was initially expected to begin in 2009 with $24 million in federal stimulus funding, but labor disputes between contractors and unions, and the project’s price tag, which inflated to $36 million, kept the work from getting started.

Nations said project planners originally anticipated the cost could be as high as $52 million due to the many “unknowns” about the bridge that would be uncovered during the renovation work.

“When you start blasting off 140 years of corrosion and paint, you’re not always sure what you’re going to find,” he said.

Credit Carolina Hidalgo | St. Louis Public Radio MetroLink trains make about 300 trips across the Eads Bridge each day.

Ultimately, 91 percent of the project was covered by federal money, including $27 million of federal stimulus dollars. The city of St. Louis chipped in a $4.8 million federal grant to the project with local sales tax dollars covering the rest of the costs. Nations said the cost of replacing the Eads Bridge with an entirely new structure would amount to more than $250 million.

The public is invited to walk out on the top deck of the bridge on Friday to celebrate the structure. Officials from Bi-State Development, Metro Transit, the Federal Transit Administration, as well as elected and civic leaders from Illinois and Missouri were to take part in the gathering. Food trucks are offering food and drinks for purchase. Festivities on the top deck of the Eads Bridge begin at 10 a.m.

Follow Joseph Leahy on Twitter: @joemikeleahy