YouTube Clip: The Long Journey
This was the situation in Freeport, Texas. One railroad bridge, built in 1914, was in advanced stages of deterioration and needed to be replaced. Another railroad bridge, an abandoned structure in Houma, Louisiana, would make a suitable, if not perfect, substitute, provided it could be moved to Freeport.
The first bridge, owned by The Union Pacific Railroad (UPRR), which services the Port of Freeport, Texas, was located on an industrial spur line that crosses the Old Brazos River, a cut-off section of the main river. Although this line is not critical to the commerce of the region - for the majority of the year it only operates twice weekly – it is very busy for a short period of the time helping to transport grain to ships. This UPRR river crossing consists of timber trestle approaches flanking a 1914 thru-truss swing span which is severely deteriorated from prevailing salt mist from the Gulf of Mexico.
The second structure, also owned by the UPRR, was a 258-ft long lift span over the Intracoastal Waterway in Houma, LA. It had been out of service and held in the raised position since the late 1980s, when this spur line was abandoned and the tracks removed. The US Coast Guard requires that all bridges over navigable waterways that are no longer in service – this one was a prime example - be removed.
The UPRR sought to solve both problems with one solution: replace the worn-out bridge with the usable, abandoned bridge. To accomplish that, they needed a bridge engineering firm with the expertise to determine if the move was feasible and how it could be accomplished.
Modjeski and Masters, designers of the Houma Bridge in the early 1980s, had previously been asked to study the feasibility of moving the structure to several other locations, including Shreveport on the Red River, and Amelia on Bayou Boeuf in Clear Lake, Texas.
The prospect of being fined by the US Coast Guard for not removing the Houma Bridge and the need to replace the Freeport swing span prompted the UPRR to make their decision – they hired Modjeski and Masters for the study on this latest proposed move. It was a clear choice given our experience. We had previously performed a similar assignment moving an abandoned railroad vertical lift bridge in Florence, AL over the Tennessee River to Hannibal, MO on the Mississippi River.
The feasibility of the movement was positive due to the following factors:
- The Intracoastal Waterway from Houma all the way to Freeport was found satisfactory for clearances and lock sizes for the transport,
- The Houma bridge can be left in major sections, i.e., lift span, sections of towers, counterweights, etc. and floated on barges to Freeport,
- Heavy lift equipment is available at both sites, and
- The major work items for this relocation include a new electrical system (vandalized), clean-up machinery, and new foundations.
The newly relocated bridge provides a 250-plus-foot channel width with a vertical clearance of 69 feet. The project was funded by UPRR.