May 25, 2013 § Leave a Comment
[MAP OF LAKE BORGNE SURGE BARRIER PROTECTIONS WITH NEW ORLEANS EAST AND ST. BERNARD RISK REDUCTION SYSTEMS. IMAGE COURTESY OF ENGINEERING NEWS RECORD]
The images that follow document a visit to arguably the most critical piece of American infrastructure built in the last decade, the Inner Harbor Navigation Canal Lake Borgne Surge Barrier. Straddling Bayou Bienvenue from the Gulf Intracoastal Waterway (GIWW) to the abortive Mississippi River-Gulf Outlet canal or MRGO (“Mister Go”), the surge barrier represents a strange kind of monstrous mea culpa from the Army Corps writ in infrastructure. While civil courts have found the Corps work in constructing MRGO did not contribute to interior flooding, independent hydraulic analysis has shown that the eroding banks of the disused canal created a wide superhighway for flood waters to access into the interior of New Orleans. Some allege that the four levee failures and considerable loss of life along the Industrial Canal–into which MRGO feeds–were directly attributable to the so-called “MRGO Funnel.”
Despite the Army Corps’ formal deflection of responsibility in court, MRGO has drawn quite a bit of the Corps attention after Katrina. In 2007, they announced that MRGO would be closed to through traffic and blocked by an earthen dam. Still other environmental advocacy groups want the entire Outlet restored to wetland habitat. Since its construction in the 1960s, MRGO’s width has nearly tripled. As vital wetland habitat is eroded, New Orleans loses a key element of its natural hurricane protection. The dilating Outlet is also introducing greater quantities of salt to intrude into marshland, further depleting delicate marsh ecosystems.
Arguably, no American city’s fortune is bound tighter to a piece of infrastructure as New Orleans is to the Surge Barrier. The largest design built project in the Army Corps history was lightly tested for first time as Isaac descended on the Crescent City. With NOAA forecasting an active hurricane season, the Corps won’t have to wait long for a a more rigorous trial.
LAKE BORGNE SURGE BARRIER , a set on Flickr.
“Recovering Together” Naturally: The Case for Natural Flood Protection in South Jersey’s Coastal Zones
February 1, 2013 § 1 Comment
Over at Design Observer, the preeminent geographer of New Orleans, Richard Campanella makes a strong plea for a balancing of the nation’s “sediment budget”, an inequality that some of our Jersey shore communities feel most acutely in the wake of Sandy. As Campanella has pointed out, the anthropogenic changes to our coasts and waterways have laid the foundation for the unprecedented economic growth of the nation:
“We routed water from wet to dry places via aqueducts, canals, pipelines and reservoirs, to be used for hydroelectricity, irrigation, municipal and industrial purposes, and upon these systems we built the world’s largest economy.”
Similarly, Atlantic City’s resort economy is built on a series of man-made infrastructural interventions: from the railroads in the 1850s to jetties and groins to the partially private-funded AC-Brigantine Connector tunnel, Atlantic City survives due to a series of public infrastructural umbilicals.
Many of these landbuilding structures currently in use by the US Army Corps along the Jersey Shore–jetties and groins primarily–do little but augment and reinforce natural depositional patterns. They’ve served to extend Atlantic City’s northern section further into Absecon Inlet; though there is not much density occupying this space. As Campanella has also expertly noted, the successes of large scale landbuilding infrastructure projects often directs development into areas of muted danger. Only during storms like Katrina and Sandy does the “obscured relevance” of these natural processes become violently apparent.
Though not a levee or a floodwall the 3,727’ Absecon Inlet jetty on the east side of the waterway is a piece of this quietly reassuring infrastructure. Designed and built in 1948 for what the Army Corps calls “channel control,” the jetty functions by creating a hard edge to capture the fleeing sands of northern Brigantine Island from entering Absecon Inlet and blocking this vital thoroughfare. Sitting 8’ above the mean high water mark, it’s also a formidable barrier which invited development along Brigantine’s Ocean Drive and Sunset Court.
[LOCATION OF ABSECON INLET JETTYS]
Yet during Sandy, the inlet crested both Absecon inlet jetties, flooding Atlantic City and severely scouring and undermining the bulkhead along Ocean Drive. According to the Atlantic City Press, a beach replenishment project amply protected the Atlantic side of the city, but the inlet and back bay sections were notoriously porous. The City and the Army Corps will soon open bids for constructing a section of seawall between Oriental and Atlantic Avenues, with another section proposed but neither designed nor funded further north.
[NOAA AERIAL IMAGERY SHOWING INLET CRESTING EASTERN JETTY 31 OCTOBER 2012]
A near constant commitment to new flood protection infrastructure has a predictable impact on development in both Atlantic City and Brigantine. Despite the proximate danger of a swollen Inlet, a new residential complex at Rum Point has just broken ground–after extensive litigation with NJ Department of Environmental Protection. Arguably, the people pay doubly when the Federal government subsidizes risky residential building through infrastructure and generous national flood insurance programs.
Yet options do exist for “softer” flood protection. One of the rare “successes” of Superstorm Sandy was found in Jersey’s protected marshlands. According to the American Littoral Society’s report on Sandy’s impact on coastal habitats, coastal restoration projects like the south Cape May Meadows (a project developed by the Army Corps, the Nature Conservancy and NJDEP) “fared very well during the storm and achieved its goal of flood protection.” Salt marshes and dune systems also blunted traumatic storm surges and waves.
The dialogue around the failures of rigid flood control systems and the embrace of more adaptive natural systems is becoming increasingly robust. Increasingly, cities in littoral areas across the globe have developed fraternities to exchange more natural techniques for combating rising sea levels. In these dialogues, ‘combat’ perhaps connotes the wrong mentality; rather many of these urban modifications allow water to coexist within cities.
Immediately after Sandy, billboards along the AC Expressway urged Jerseyans to bounce back with “Jersey Strong” vigor. One simply said “Recovering Together”. What if this was an exhortation to rebuild together with natural processes? With Atlantic City’s lack of density, wouldn’t it be interesting to see an entire northern area riven through with salt marshes, tidal creeks and–instead of simply allowing north Brigantine Island to become south Brigantine Island–we balance the sediment budget and create an extensive urban dune system?
January 15, 2013 § Leave a Comment
[BE SURE THE TRACK IS CLEAR BEFORE YOU ENTER]
[Historic benzene formulae (from left to right) by Claus (1867), Dewar (1867), Ladenburg (1869), Armstrong (1887), Thiele (1899) and Kekulé (1865). Dewar benzene and prismane are different chemicals that have Dewar’s and Ladenburg’s structures. Thiele and Kekulé’s structures are used today.]
January 5, 2013 § Leave a Comment