Harris County is looking for a new bridge design engineer after it fired FIGG from the US$1 billion Houston Ship Channel Bridge replacement project.
Last month, Harris County fired FIGG, which had already completed around $400 million worth of work, citing issues with the engineering firm’s design, according to local media reports.
The design by FIGG Bridge Engineers – a company which has won multiple design awards in the past 40 years - was approved in 2017. Work started in March 2018 for completion in 2024, although activity had been low on site since January.
According to a report by local television station KPRC in Houston, Harris County hired engineering firm COWI in March 2019 to conduct an independent review of the 829m-long bridge work. The resulting report cited 21 what it called “significant” design flaws.
FIGG’s problems had started earlier when in March 2018 a pedestrian bridge in Florida that had been designed by the company collapsed onto a highway, killing six people. In July this year, the US Federal Highway Association suspended FIGG Bridge Engineers from participating in federally-funded projects and proposed a 10-year suspension.
The KPRC-TV report said that Harris County Commissioners will likely hire COWI, the firm that conducted the independent review, as the new bridge designer. The contractor is Ship Channel Constructors, a joint venture of Traylor Bros and Zachry Construction.
The Houston Ship Channel, in Houston, is part of the busy Port of Houston. Ocean-going vessels ply between Houston-area terminals and the Gulf of Mexico and the channel has an increasing volume of inland barge traffic.
According to the website of FIGG, the bridge’s cable-stayed main span structure features a 400m-long ree span over the channel. It has more than 57m of vertical clearance for navigation, allowing future widening and deepening of the channel by the Port of Houston. The eight-lane bridge is part of the programme to widen the Sam Houston Tollway (East).
The pylons will be 157m high and the foundations are built outside the waterway to minimise environmental impact as well as enable future channel widening.
A report in the summer edition of the American Segmental Bridge Institute, noted that the design is for 25m-wide and 3.6m-deep precast concrete segmental superstructures that will support four lanes of traffic in both directions. The magazine’s report details the on-site concrete segmental work.