As demonstrated in the above photo, the GAO report noted that having the old road adjacent to the new one and documenting impacts to both is a good start in moving towards understanding the benefits of investments in adaptation.
A new federal report recognizes the 11-mile stretch of elevated LA Highway 1 between Leeville and Port Fourchon as a shining example of resilient infrastructure projects designed to withstand future sea level rise. The report, issued to Congress by the U.S. Government Accounting Office (GAO), also calls attention to the continued vulnerability of Hwy. 1 north of Leeville to rising water and subsidence, and its critical importance to the U.S. energy supply.
“Louisiana State Highway 1…demonstrates in near-real time the benefits of specific adaptations in design,” cites the GAO. “Having the old road adjacent to the new one and documenting impacts to both is a good start in moving towards understanding the benefits of investments in adaptation as opposed to investing in disaster recovery.”
Climate Change: Future Federal Adaptation Efforts Could Better Support Local Infrastructure Decision Makers details the threats posed to our nation’s highways and bridges by climate change impacts, and provides specific examples of infrastructure at risk and efforts that have helped protect America’s infrastructure assets. A team of analysts conducting research on LA Highway 1 visited the corridor in May and September 2012 to evaluate the highway for inclusion in this report.
“A coalition of state and local officials worked together to obtain funding to raise an 11-mile segment of the highway (LA 1) by 22.5 feet to protect the road from 100-year flood events. To further protect the road from storm surge, bridge designers used restraining devices and anchor bolts to prevent the road deck from dislodging from the rest of the structure in the event of a large storm surge,” the report explains.
The research team’s September 2012 visit followed Hurricane Isaac’s landfall in southeast Louisiana, and noted the elevated highway’s resilience following the storm.
“The raised segment of Louisiana State Highway 1 was largely unaffected by Hurricane Isaac— the first major hurricane to hit since the raised segment was open to the public… the raised section’s superstructure, which includes the girders, was unaffected despite the approximately 6.5-foot storm surge measured at Port Fourchon… In contrast, the unraised sections of the highway both north and south of the raised road were damaged,” states the report.
“Sections of Louisiana State Highway 1…are… in a particularly vulnerable location near the Gulf of Mexico… The highway provides the only road access to Port Fourchon, which services virtually all deep-sea oil operations in the Gulf of Mexico, and the Louisiana Offshore Oil Port, the nation’s only deepwater oil port capable of unloading very large crude carriers… LA Highway 1 currently supports 18 percent of the nation’s oil supply. Flooding of this road effectively closes the port,” according to the GAO report.
The GAO utilized the inundation data from the National Oceanic and Atmospheric Administration (NOAA) to advise federal policy makers of the continued risks faced by at-grade LA Highway 1 from Leeville to Golden Meadow and how soon the road will experience repeated closures due to subsidence and sea level rise. According to a 2012 NOAA study, relative sea level rise near LA Highway 1 is one of the highest levels in the world at approximately three feet over 100 years. The impacts to our infrastructure, economy, and energy supply are significant.
As cited in the report, “Currently, Louisiana State Highway 1 is closed an average of 3.5 days annually due to inundation. However, within 15 years, NOAA anticipates that the at-grade portions of Louisiana State Highway 1 will be inundated by tides an average of 30 times annually even in the absence of extreme weather. Because of Port Fourchon’s significance to the national, state, and local oil industry, the U.S. Department of Homeland Security, in July 2011, estimated that a closure of 90 days could reduce national gross domestic product by $7.8 billion.”
LA 1 Coalition Executive Director Henri Boulet says recognition of LA Highway 1 in this impressive federal report reinforces the Coalition’s efforts to garner federal support to elevate the vulnerable Leeville to Golden Meadow highway segment.
“It is significant to have a federal agency of the Government Accounting Office’s magnitude issue a report to Congress that commends our local and state effort for designing our elevated highway resilient to 100-year flood events and the storm surge these events bring. The report’s recognition of the continued vulnerability of our at-grade sections of LA Highway 1 is also important,” says Boulet. “This report clearly demonstrates why we must move forward to complete the second phase of the LA 1 Improvement Project -- to reduce the impacts of relative sea rise and subsidence on this critical energy infrastructure, and ultimately secure our nation’s energy supply.”
U.S. Senators Sheldon Whitehouse and Max Baucus announced the release of the GAO report to Congressional colleagues, advocating for climate change adaptations in national infrastructure planning. The Senators mentioned LA Highway 1 in a joint statement, noting, “Louisiana State Highway 1, which provides access to a port servicing 18 percent of the nation's oil supply, is expected to be at greater risk from flooding as a result of rising sea levels.”
The complete GAO report, Climate Change: Future Federal Adaptation Efforts Could Better Support Local Infrastructure Decision Makers, can be viewed at www.gao.gov /products/GAO-13-242.
The LA 1 Coalition is a 501(c)4 non-profit corporation working for highway improvements from U.S. Highway 90 to the coast in Lafourche Parish, Louisiana, along the Louisiana Highway 1 corridor. For more information, visit www.La1Coalition.org.
Posted on Fri, May 17, 2013