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PennaGroup strongly supports the Coastal Barrier System (also known as "Ike Dike") which is a proposed coastal barrier that, when completed, would protect the Texas coastal cities.

Specifically, the project would dramatically enhance the existing Galveston Seawall, complete with floodgates, and would protect more of Galveston, the Bolivar Peninsula, the Galveston Bay Area, and Houston. The barrier would extend across Galveston Island and the Bolivar Peninsula and would provide a barrier against all Gulf surges into the bay.


Category 5 Storm. The proposal, as the name suggests, is motivated by the damage caused by Hurricane Ike in 2008 (a Category 4 storm) that wreaked havoc on infrastructure, agriculture, and refineries across Texas, resulting in $37.5 billion in damages and causing 195 deaths.

The purpose of Coastal Barrier System is to prepare against a Category 5 storm. Historically, the worst storm Texas suffered was a disastrous Category 4 storm called the "Great Galveston Hurricane" of 1900 that left 12,000 Texans dead. A Category 5 storm would be exponentially worse.


Notably, the Coastal Barrier System would be able to withstand a 10,000 year storm.


National Security Threat. Beyond the severe and unacceptable loss of life and property, a Category 5 storm presents an extreme national security risk. The Houston area (particularly the Bay Area) is home to the largest and most important concentration of petroleum refining and petrochemical processing plants in the United States, and most of these plants are on the coast or on the ship channel.


Almost Happened. Most experts agree that had Hurricane Ike made landfall about 30 miles to the west, it would have sidelined 40% of U.S. jet-fuel production including serious setbacks to the production of gasoline and other chemicals. Notably, the Port of Houston is the second-busiest port in the nation. Hurricane Ike was headed on a direct collision course with the Port of Houston, but changed course at the last minute.


Luck, Not Planning, Won the Day. With Hurricane Ike, we dodged a bullet. But we cannot simply cross our fingers again hoping for another miracle. Not with so much at stake.


Russian Roulette. A major hurricane hits the Texas Gulf Coast every 15 years on average. It's been a while since the last devastating storm, Hurricane Ike in 2008. So every year that goes by without an additional coastal barrier is like playing Russian Roulette. As bad as Hurricane Ike was, people who live and work in Galveston and Houston understand we dodged a bullet.

We were looking at possibly a $100 billion hurricane, that could have killed hundreds, left thousands homeless and jobless and devastated the nation’s largest petrochemical complex and crippled its busiest port. 


Worst Case Scenario Prevention. Thankfully, the technology exists to prevent this terrible scenario. The Ike Dike team at Texas A&M University, Galveston Campus has proposed a plan that includes best practices and existing technologies used in the Netherlands and New Orleans to protect our region.

The coastal spine concept is the approach the Dutch used after their 1953 surge disaster. They shortened their coast by combining barriers and gates to keep surge out of internal waters. They shared their methods with New Orleans after Hurricane Katrina, and today New Orleans has the Greater New Orleans Barrier that protects the city from storm surge. We are using that knowledge here as a solution to protect the Galveston-Houston area.


Becoming a Part of the Solution. PennaGroup has exhausted many resources to become a part of the solution. To that end, we have sought out the best advice from the top experts in the field, including hydrologists, structural design engineers, and manufacturers of gabion baskets and mattresses all of whom share our common belief in fortifying the existing coast and creating a sorely-needed coastal barrier.


Coastal Spine. In order to prevent the coming devastation (which is a matter of "when", not "if"), Bill Merrell of Texas A&M University at Galveston calls for a "coastal spine" which includes building 55 miles of dune barriers and gates at the mouth of the Houston shipping channel, stretch from Bolivar Peninsula to the San Luis Pass. As Merrell says, "The concept is easy. You stop the storm surge at the coast so that you protect everyone."


PennaGroup's Design Proposal. PennaGroup has teamed with its vendors to propose their ideas on building the "coastal spine" system which includes 17-foot high sea wall that would be disguised as sand dunes. Based on the beautiful Netherlands dune systems (as proposed by Bill Merrell of Texas A&M University at Galveston), PennaGroup's dune barriers would be invisible at the surface, but made of modular gabion baskets and mattresses underneath. With PennaGroup's beautiful dune system, it would be impossible to tell which dunes are real and which are artificial.


USACE Project/Florida DoT, State Road 196 (Bayfront Parkway) - Construction Phase USACE Project/Florida DoT, State Road 196 (Bayfront Parkway) - Post Construction

Twisted Wire vs. Welded Wire Gabion Baskets. Used successfully by many U.S. Army Corps of Engineer Districts, modular welded wire gabion baskets have several distinct advantages over twisted wire gabion baskets including (1) installation cost savings; and (2) lifecycle cost savings. The difference means millions of dollars of revenue spending saved annually on public works, flood control, channel rehab, and coastal barriers, such as the Coastal Barrier System.


Installation Cost Savings. While the cost of modular welded wire gabion baskets is slightly higher than twisted wire gabion baskets, the project labor installation costs savings are significant. In most cases, modular gabions can be installed in half the time. This fact is borne out by the U.S. Army Corps of Engineer - Philadelphia District's side-by-side study for the Cape May Canal Project - Phase V (compared welded wire gabions side-by-side with twisted wire gabions). See article here.

The Results. As stated by Megan Coll, the U.S. Army Corps of Engineers Project Manager, "There was a definite installation time advantage to the welded wire gabions." According to the Phase V - Daily Project Logs, it took approximately:

  • 55 working days to install 350 LM (1,148 LF) of hexagonal twist wire gabion revetment, and
  • 34 working days to install 370 LM (1,214 LF) of the welded wire gabion revetment.

That equates to 6.36 LM/day (20.87 LF/day) for the twist wire versus 10.88 LM/day (35.7 LF/day) for the welded wire - a substantial 71% faster installation rate.


Experienced Installers. It should be noted that the prime contractor in this 1996 study, Trevcon Construction Company, Inc., was a first-time installer of the welded wire gabion baskets. Experienced modular welded wire gabion basket installers can further reduce the installation rate to 100% of the time on average.


Life Cycle Costs Savings. In addition to the significant reduction in installation time, modular welded wire gabions will not suffer complete failure when even slight changes occur in their foundations. As anyone who has ever been tasked with maintenance of twisted wire gabion failure (natural or in some cases vandalism), the compromise of a twisted wire system is like pulling on a thread of a tapestry, the entire section can become compromised and in need of replacement.

Modular Advantage. Unlike the twisted wire system, a failure of a modular welded wire gabion system will be, as the name suggests, "modular" in nature. In other words, when a twist wire system fails, often the customer will need to replace the entire section - but with a modular system, only the specifically failed modules will need replacement. This replacement/maintenance advantage translates into millions of dollars savings to the customer.


Modular Welded Steel Wire Mesh Gabions Welded Steel Wire Mesh Gabion Mattress

PennaGroup Selection. Based on these established advantages, in addition to being far more aesthetically pleasing, PennaGroup selected modular welded wire gabion baskets for its design-build bank stabilization projects. Other examples of modular gabion baskets and mattress are as follows:


Note - images courtesy of C.E. Shepherd, PennaGroup's manufacturer of all modular welded steel wire gabion products.


For more information about any of our past or current projects, please contact us via email or call us at (817) 546-7250.


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