GICA Attendees Get In-Depth Look At Brazos Replacement Project
The sheer frequency of allisions at the Brazos River Floodgates on the Gulf Intracoastal Waterway (GIWW) near Freeport, Texas, is astonishing.
Speaking to GIWW stakeholders who gathered in New Orleans July 28 for the annual seminar of the Gulf Intracoastal Canal Association, Rob Dauenhauer with the Inland Navigation Design Center compared the difficulty of navigating the existing sector gates on either side of the Brazos River to driving a car without brakes.
“Brazos would be kind of like this: If your car didn’t have brakes and the concrete was about 6 inches from each edge of the car,” Dauenhauer said. “And that’s on a good day with ideal conditions, right? Here, they’ve got wind, currents, tides, everything else in the world to deal with.”
The existing gates were built in the 1940s and are only 75 feet wide. The floodgates were installed to control flows and sediment from the Brazos River, but “the geometry and the width of the crossings created some really hazardous crosscurrents,” Dauenhauer said.
With a tank barge around 35 feet wide, and two amounting to 70 feet across, that leaves little room to spare going through the existing floodgates.
“We end up with an allision on average about once every five days,” Dauenhauer said. “You look at that, and you’re like, ‘Wow, that’s a lot.’ But if you’ve been through there, you’re like, ‘Wow, that’s not as much as I was expecting,’ right?”
Dauenhauer then detailed the collaboration between the Corps and industry, including extensive modeling in simulators, to arrive at the planned replacement design for both Brazos and the Colorado River Locks to the west. The Corps plans to create a 125-foot open channel on the west side of the Brazos River, along with a new 125-foot-wide floodgate on the eastern side of the river. According to Dauenhauer, the feasibility study for the project started in 2016, with a signed Chief’s Report following in 2019. The Water Resources Development Act of 2020 authorized both Brazos and Colorado, which were taken together as one mega project, for $414 million.
“The current estimate, based on our latest escalated cost estimates in our upcoming cost certification for both projects together is roughly around $844 million,” Dauenhauer said. “Some of the reasons for that cost increase are we’ve got some inflation, some transportation issues, labor issues. Pretty much every estimate done before the pandemic, you can count on it being almost double what it was.”
Cost escalations across the board have put funding for Brazos in jeopardy, with Corps and industry officials advocating for splitting the Brazos project into west and east phases and using $80 million to remove the western gate and establish that 125-foot channel.
Dauenhauer said the western gate is essentially inoperable from so many allisions, so adjusting to a gate-free western side should be an easy transition.
“For about the period of the last year, we’ve actually kept that gate open to help simulate what the open western channel will be,” he said. “Right now, it’s not a huge impact to navigation.”
And since the existing structure will eventually be demolished to make way for the larger channel, the Corps is in no hurry to spend money to fix it.
“We know that, if you can get construction going, if we can demolish the structure, if we can get started, there’s no need for us to do any kind of repair or anything on these gates,” he said. “So we’re trying not to spend those dollars where they really won’t get any benefit from it.”
The Corps had planned to advertise and award the construction contract for Brazos in fiscal year 2024, but with the funding shortfall, the project will have to receive an additional appropriation to proceed.