Environment Issues In New Orleans

By Richard Campanella

Participants at the ELCA Youth Gathering may recognize many of New Orleans’ environmental challenges as similar, in form if not in magnitude, to those facing their home cities. At another level, however, they are like no other in the country. Within city limits, New Orleans’ environmental problems indeed resemble those found in other old American port cities:

o Inner-city neighborhoods, for example, suffer from high levels of heavy metals in their soils, caused by traffic congestion and lead-based paint and shown to have adverse health affects on children.
o Old industrial sites and dumps leave behind contaminants and potentially harm residents of nearby neighborhoods build decades later.
o Suburbanization displaces forests and wetlands, diminishing wildlife habitat while increasing impermeable concrete surfaces.
o Drinking water for the entire metropolis comes from the Mississippi River, which collects across its million-square-mile basin pollutants such as coliform bacteria and the weedkiller atrazine, not to mention those spilled in the river itself. (A vessel collision in July 2008 shut down navigation traffic and water intakes for days when 400,000 gallons of oil leaked into the Mississippi.)
o Numerous petrochemical plants and other industries along the nearby River Road release millions of pounds of toxins annually, leading some to call the New-Orleans-to-Baton-Rouge corridor “Cancer Alley.”
o Louisiana’s semi-tropical climate and coastal environment also allow a disproportionate number of invasive species to establish themselves here, including Formosan termites, which threaten the city’s historic housing stock and graceful live-oak trees.
o Poverty, inadequate education and health-care systems, and other social problems leave the New Orleans population ill-prepared to deal with, let alone solve, these environmental challenges, problems of urban sprawl and air, soil, and water pollution facing most American cities.

Beyond city limits, however, the premier environmental challenge is anything but familiar to the rest of the nation. It represents the single most serious threat a region can face: the disappearance of its very geological base. Southern Louisiana has lost over 2000 square miles of coastal wetlands since the 1930s.The loss has claimed vast expanses of productive ecosystems and forced rural Louisianians to tear up centuries-deep roots. Now the erosion threatens urban areas: approximately every 2.7 linear miles of wetland loss allows one extra vertical foot of seawater to surge inland toward the metropolis in front of a tropical storm. A number of interrelated factors drive coastal erosion.

o First, flood-control structures — namely artificial levees — erected along the lower Mississippi River since the 1700s have succeeded in preventing springtime floods, but inadvertently starved the region of annual deposits of replenishing freshwater and flood-borne sediments.
o Second, an extensive network of navigation, oil, gas, and drainage canals increased the extent of land/water interfaces and saltwater-intrusion routes, and thus opportunities for erosion and swamp die-off.
oThird, soils drained of their water content, through municipal drainage or flood-control projects, sink under their own weight. Metropolitan New Orleans has subsided by as much as eight to twelve feet in some areas, such that roughly half the city now lies below sea level.
o Fourth, gulf waters are gradually rising, as global temperatures increase and ice sheets melt.
o Finally, saltwater marsh grasses die off because of salinity, drought, or invasive rodents (nutria), rendering the delicate marshes even more vulnerable to wind and water erosion.

When Hurricane Katrina struck in August 2005, eroded wetlands and manmade canals allowed high gulf waters to reach low-lying populated areas. Poorly constructed federal levees failed, and salt water poured into subsided urban neighborhoods. The very levee system designed to keep water outended up trapping water therein, for weeks. In a matter of hours, Hurricane Katrina revealed the folly of a century of environmental neglect, and over 1500 people perished in the process.

There is hope; this is a solvable problem.

River diversions and siphons must be deployed to re-create the historical tendency of the Mississippi to overflow and replenish the coastal wetlands with fresh water and sediment, without the deleterious effects of flooding. Sediment-mining operations are needed to supplement the inadequate quantities of sediment now in the river. Coastal wetlands and barrier islands must be rebuilt to buffer southern Louisiana from future Katrina-like storms.

New Orleans is blessed with the world’s greatest land-building machine, the Mississippi River. What is needed is the national will to restore its natural geological function of building up the deltaic plain.
Human beings are capable of amazing things when they share a common vision and confront a shared problem. Your work here in New Orleans represents the sort of commitment and willpower required to restore Louisiana’s environment and save the national treasure that is New Orleans.

Richard Campanella is a geographer at Tulane University