Engineers are getting better at picking up the pieces after hurricanes and reducing the next-flood risk in devastated areas. But places vulnerable to catastrophic events generally must wait until they have been wrecked before significant risk-reduction measures are planned, funded and applied.
As the 2009 hurricane season opens, $14.3 billion worth of levee repairs and new defense construction is roaring ahead in the area smashed by Hurricane Katrina in 2005. Construction began in May on a massive, roughly $1.8-billion surge barrier to protect the southeastern flank of New Orleans, where the Corps of Engineers has pledged to achieve by the 2011 storm season protection against surges with a 1% probability of occurring in any year. A second $500-million-plus barrier of similar size, further south, is in late stages of design.
But planners are looking beyond 2011, when a desperate need to restore vanishing coastal wetlands, which are a significant surge buffer, will run into a funding gap expected to last until the state can begin to tap oil and fuel tax revenue walled off by Congress until 2017. It is the kind of preventive work that falls behind during last-storm damage repair.
In Grand Isle, La., where coastal dunes were wrecked by hurricanes Ike and Gustav last year, Weeks Marine, Cranford, N.J., is working on a $25.7-million, 5.7-mile-long beachfront berm rebuilt around a 8.5-ft-high by 14-ft-wide sand-filled geotube-core. The dune is to be raised to a +13-ft elevation by the end of September. In Galveston, Texas, David Boland Inc., Titusville, Fla., also started work in May on a $10.5-million contract with the Corps to repair rock groins and multiple sites on the city’s seawall in one of the larger contracts for Hurricane Ike damage repairs in the area.
But concepts for building new protections, such as an “Ike Dike”—a surge barrier to protect Houston and its port-side petrochemical complex, which was spared an 18-ft surge last year by Hurricane Ike’s 5º twitch to the north at landfall—remain just that: concepts.
“There is an idea out there. That’s all it is right now,” says D. Wayne Klotz, president of the American Society of Civil Engineers. “Ike Dike is an interesting idea, but it has no official sponsor and no official status. That turn to the north made a difference in about $2 billion or $3 billion worth of damage”—and an immense disruption to the national economy.
However, predictions of climate change and sea-level rise in the next decades are sharpening attention of increased risk to coastal infrastructure from many threats, including storm surge, not only on the U.S. hurricane coast but worldwide. Klotz says the challenge will be to focus public attention there.
The National Oceanic and Atmospheric Administration reports global weather patterns are bringing greater uncertainty to this season’s storm-season forecast than in recent years. It says there is a 50% probability of a nearly normal season, with a 25% margin of error. NOAA forecasts a 70% chance of having nine to 14 named storms, four to seven of them hurricanes, with one to three such storms reaching category 3, 4 or 5 intensity.