Posted on April 19, 2023
Coastal real estate must adjust to climate change and increasingly erratic weather, and Texas is leading the way. Spurred by heavy damage caused by Hurricane Harvey in 2017, the U.S. Army Corps of Engineers and the Texas General Land Office are mounting a $31 billion coastal resilience project on the Texas coast, the most expensive project ever led by the Corps and the largest coast management project ever.
At the ULI Coastal Forum, held in October at the 2022 ULI Fall Meeting in Dallas, about 45 ULI members heard expert panels deliver key insights on the state’s coastal issues and solutions to bring about greater resilience.
With a coastline over 3,300 miles (5,300 km) long and the greatest number of annual federally declared natural disasters of any state, Texas also has the country’s fastest-growing population, and 6 million of Texas’s 29 million people live along the coast.
To protect billions, perhaps trillions, of dollars of real estate and the threat to human life and infrastructure, the state of Texas conducted a six-year, $20 million Coastal Texas Protection and Restoration Feasibility Study and environmental impact statement, which yielded a plan: the Coastal Texas Resiliency Improvement Plan. Released in March 2019, the plan offers an integrated and comprehensive coastal resilience strategy for the Texas coast.
In September 2021, Scott Spellman, commanding general of the U.S. Army Corps of Engineers, signed the Chief’s Report—the largest single investment recommendation to the U.S. Congress in Corps history. As part of the Water Resources Development Act of 2022, it is anticipated that Congress will formally authorize advancing the Coastal Texas Program into design and construction, pending appropriation of funds.
The project is being led by Kelly Burks-Copes, project manager for the Corps of Engineers, Galveston District, and nonfederal partners, the Texas General Land Office, and the Gulf Coast Protection District. It is estimated that every day of delay in beginning the projects adds $3 million to overall project costs. In addition, once constructed, it will cost $130 million to $140 million per year just to operate.
The coastal resilience plans feature two principal intersecting elements:
• The Coastwide Ecosystem Restoration Plan, along nearly the entire Texas coastline from Galveston to Corpus Christi, to improve resilience using mostly nature-based solutions; and
• The Galveston Bay Storm Surge Barrier System, an elaborate battery of coastal defenses surrounding Galveston Bay using extremely robust manmade heavyweight engineering solutions, to protect the Houston Ship Channel and the Port of Houston.
Restoring the Coastal Ecosystem
Natural solutions to coastal water-related events, such as storm surge, tidal erosion, and sea-level rise, have an increasingly important role in ensuring that coastal areas are resilient. “Nature-based solutions that are designed with a view to the whole system—meaning both the natural and human-made environments—can be key for improving resiliency of an area or region over the long term,” Taylor Nordstrom, a coastal engineer for AECOM, said in an interview.
Natural solutions involving ecological restoration to create “living shorelines” are increasingly found to improve resilience against rising waters. Such solutions slow, hold, and absorb rainwater, mitigate flooding and erosion, capture nutrients, and filter water. They also provide habitat connectivity and biodiversity, store carbon, moderate temperatures, improve air quality, and provide access and recreation. Natural solutions can replace, or supplement, traditional hard engineering solutions.
Natural solutions are normally much lighter weight than many typically concrete-based engineering solutions. Seventy percent of coastal and marine structures are concrete based, says Karin O’Brien, technical director for business development for ECOncrete. Concrete barriers are problematic because they can be so heavy that they cause the land on which they are constructed to sink.
Jim Blackburn, chief executive officer of BCarbon, noted at the Coastal Forum that the Texas coast is a low-lying area. Because it is relatively flat, during a flood event, floodwaters penetrate far inland, giving nature-based solutions an important role to play.
Risks and Concerns
The Coastal Texas Resilience Plan identifies eight priority concerns—encompassing risks and threats to the viability of coastal communities, habitats, and industries—that can be addressed by nature-based solutions: altered, degraded, or lost habitat; gulf beach erosion and dune degradation; bay shoreline erosion; existing and future coastal storm surge damage; coastal flood damage; impact on water quality and quantity; impact on coastal resources; and abandoned or derelict vessels, structures, and debris.
To address these concerns, the Corps and General Land Office are conducting landscape-scale acquisitions at both South Padre Island and Bahia Grande; promoting living shorelines through coastal restoration and management; restoring and managing oyster reefs; and assessing the viability of introducing coastal wetland projects to the voluntary blue carbon market, among other actions.
Mangrove trees, for example, can act as natural soil stabilizers. In general, plants reduce wave energy as water passes through them, preventing erosion. Protecting wetlands in turn protects their capacity to sequester and store carbon.
Concepts addressing floodplain issues are also shifting toward restoring the natural floodplain. Previously, engineers sought to fill in floodplains in order to move water away from cities quickly. Now, engineers focus on leaving at least enough of the floodplain that some surface water can percolate into the groundwater.
While nature-based solutions are catching on, they must be scaled up to achieve the most widespread acceptance and impact. To do that effectively, the state of Texas must provide local government staff, planners, and communities with decision-making knowledge and tools to enable use of these solutions.
Regional stakeholders must develop and facilitate a planning process to create a prioritized portfolio of nature-based solutions throughout the relevant area. Finally, governments at all levels must encourage the adoption and implementation of the applicable portfolio of nature-based solutions by providing technical assistance and supporting capacity building.
The Corps has created an assessment tool that facilitates cost estimates of natural-based options, Nordstrom said in an interview. “Ecosystem restoration can be an effective option to improve resiliency to hazards like coastal flooding, especially when it is done as a hybrid solution along with traditional engineered structures,” she said.
The Coastwide Ecosystem Restoration Plan also integrates measures included in the Galveston Storm Surge Barrier System to protect the shoreline from erosion and restore marshes and oyster reefs, which will enhance the resilience of the adjacent structural, natural, and nature-based risk-reduction measures.
Environmental mitigation will be needed to offset the direct and indirect environmental impacts of development and construction of the mammoth Galveston Bay Storm Surge Barrier System. As currently envisioned, more than 1,300 acres (500 ha) of habitat are proposed to be created or enhanced for such mitigation.
Storm Surge Barrier System
The Port of Houston includes both public terminals and private terminals for companies like Exxon Mobil and big container companies, Rich Byrnes, chief infrastructure officer of Port Houston, said at the forum.
He put the annual economic impact of the Port of Houston at 1.23 million Texas jobs, 3.2 million jobs nationwide, and $339 billion of economic impact just in Texas—one-sixth of the annual gross state product—as it handles about 16 percent of all U.S. port cargo.
Unless protection is provided by the Galveston Bay Storm Surge Barrier System, a major ocean storm surge could pass from the Gulf of Mexico through the channel of the Bolivar Roads strait into Galveston Bay, then up the Houston Ship Channel to the Port of Houston—obliterating everything in its path and wreaking devastation on property, infrastructure, and human life.
As Hurricane Harvey demonstrated, if the Port of Houston shuts down for any length of time, it will cause catastrophic interruptions to the global value chain and could ignite a global recession, Byrnes said.
A big storm hits the Galveston area every seven years, Burks-Copes noted at the forum. The proposed Gulf defenses separate the Gulf of Mexico from Galveston Bay to reduce ocean storm surge entering the bay and to provide direct protection for communities on the Galveston barrier island.
The largest single component of both the Galveston Bay Surge Barrier System and the Gulf defenses will be the Bolivar Roads Gate System, a two-mile-long (3.2 km) ocean storm surge closure structure with two pairs of vertical gates, corresponding to two deep draft navigation channels, one for ships entering Galveston Bay and another for those exiting. The massive gate will span the east–west “strait” between Galveston Island to the south and the Bolivar Peninsula to the north, through Galveston Bay and west to the entrance to the Houston Ship Channel.
The multipart Bolivar Roads Gate System is intended for severe storm surge emergencies only and will remain open unless the region is threatened by a tropical storm. At all other times, it will allow normal navigation and environmental flows, including allowing fish to move in and out of Galveston Bay.
The Texas coast and port will also be protected by 43 miles (69 km) of beach and dune segments on Bolivar Peninsula and Galveston’s West End that interlink with the Bolivar Roads Gate System to form a continuous bulwark of defense against ocean storm surge, preventing or reducing surge volumes that would otherwise enter the bay system. Yet another defense will consist of improvements to the existing seawall on Galveston Island to complete the continuous line of defense against Gulf storm surge.
The bay defenses will enable the system to manage residual risks from the run-up of water already in the Galveston Bay system, plus any additional storm surge that overtops the Bolivar Roads Gate System or other parts of the Gulf line of defense. The bay defenses also will provide further resilience against variations in the storm track and intensity, and relative sea-level change.
The Coastal Texas Resiliency Improvement Plan embraces balanced integration of both the latest natural solutions and traditional heavy-duty engineering solutions, culminating in the Galveston Bay Storm Surge Barrier System, which masterfully combines the two.
This integration of the widest variety of solutions into an optimal operating plan is in turn made possible by the collaboration of a wide range of open-minded stakeholders, including private sector–related organizations like Port Houston, federal government agencies like the Army Corps of Engineers, Texas state government agencies like the General Land Office, and environmental nonprofits like the Nature Conservancy—as well as a strong process for collaboration through technical advisory committees and community work groups.
What the Army Corps of Engineers and Texas General Land Office are doing on the Texas coast to combat storm surge and the impacts of climate change demonstrates on a grand scale that practical solutions to complex coastal resilience and climate change issues can be designed and implemented, and that these vital issues can be managed.