The bridge that carries Monroe Street over the Buffalo and Pittsburgh Railroad tracks in Butler will be replaced this year.

The project was reviewed May 1 by the Public Utility Commission, and after a 20-day period for comments, it can be put out to bid.

Construction could start at the end of July and the new $2.1 million bridge could be open in the spring of 2009, said John Evans, the city's zoning officer.

It will be funded with 80 percent federal money, 15 percent state, and 5 percent, or $105,000, will be divided among the city, county and railroad. The city will be in charge of the project, Mr. Evans said.

The bridge is at least 60 years old and hadn't been inspected by the county before 2004, he said.

The Buffalo and Pittsburgh Railroad maintained the bridge, and the city believed it needed some maintenance. The city sought the help of the PUC, which oversees railroads, and the PUC recommended that the bridge be inspected.

The city hired Widmer Engineering, the Butler County engineer, in 2004. Widmer found the piers holding up the bridge were unsafe, and the bridge was closed for a few months. The railroad repaired the bridge and it was reinspected and reopened with a 5-ton weight limit.

Mr. Evans said the city has been trying to get the Monroe Street bridge replaced in time for the state Department of Transportation's next construction project in the city. Monroe Street will be a major detour when PennDOT replaces the Wayne Street bridge. Construction on that bridge will begin in August.

Mark Hillwig, PennDOT community relations coordinator, said PennDOT is moving ahead with both projects and has developed traffic control plans for both bridges. He said a detour for the Wayne Street bridge will not be needed until next spring when the Monroe Street bridge replacement is expected to be finished.