JUNEAU, Alaska (AP) Work has begun in preparation of construction of a new Mendenhall River bridge that will replace Juneau’s historic Brotherhood Bridge.

Plans call for the old bridge to be removed and disposed of by the end of the year. The new, wider bridge that will replace it will be able to handle an expected 50 percent increase in traffic over the next 75 years, KTOO reported Friday.

The work currently being done involves steel pieces that are being driven into the river bottom for a trestle.

The trestle will cross the river and serve as a platform for equipment used in constructing the replacement bridge, said Senior Project Manager John Smithson of Orion Marine Contractors.

The half-century-old Brotherhood Bridge does not meet current code, state Department of Transportation Engineering Manager Greg Lockwood said. The pilings of the bridge, for example, go down only 45 ft. (13.7 m) into deposits that would be subject to liquefaction during a major earthquake.

The pilings of the new bridge will go to the bedrock or as deep as 290 ft. (88 m).

The $25.1 million project also is expected to improve pedestrian and vehicle traffic on a section of Glacier Highway.

On the new bridge, each direction of travel will have two lanes. Also, the roadway on both sides of the bridge will be expanded, Lockwood said.

Before the current bridge is removed in November, the upstream span of two lanes of the new bridge will be built to allow traffic to cross the river, Smithson said. The downstream side will be built after that.

The project is expected to be finished by late October 2015.

The Brotherhood Bridge had bronze medallions that were installed when the original bridge was dedicated in 1965. Those medallions have been recovered and will be installed in the handrail of the new bridge.