It’s all there including the area’s importance to the petroleum industry. The Baltimore Sun did an article with the same geologist just before the storm hit.
For historic city, a fateful forecast
Disaster modeling indicates storm such as Katrina could flood low-lying city, killing tens of thousands
By Frank D. Roylance
Sun Staff
August 29, 2005
baltimoresun.com.
With Hurricane Katrina bearing down on the Gulf Coast yesterday with the threat of a 25-foot storm surge and 15 inches of rain, the city of New Orleans could hardly be in greater natural peril.
The city, founded by the French in 1718 on what seemed relatively safe high ground beside the Mississippi River, is now situated 6 to 8 feet below sea level, in a saucer of silt, sand and clay.
The river and Gulf of Mexico are held back by a system of levees and storm gates. And every inch of water that seeps in, or rain that falls, must be removed by one of the world's largest pumping systems.
That system could undergo its biggest test today as New Orleans faces one of the most powerful storms ever to threaten the United States.
Disaster modeling suggests that the consequences of a Category 5 storm such as Hurricane Katrina could be dire -- pumps disabled by flooding, 20 feet of water in the streets and tens of thousands dead. Experts have warned that the city could be left paralyzed for months by water, debris, demolished buildings, and a hazardous soup filled with sewage, petrochemicals, alligators and fire ants.
"Everyone keeps saying, 'This is the big one. This is the one that could tell us how leaky that hurricane protection system is,'" said University of New Orleans geologist Shea Penland. "I hope not. I hope the risk won't be counted in body bags."
Penland sent his family to Shreveport, about 280 miles away. Most have left New Orleans, but he is staying. He and his golden retriever are holed up with a generator in his century-old Victorian home, built on one of the city's levies.
"I'm in the business, and this one's coming right to me," said Penland, director of the university's Ponchartrain Institute for Environmental Science. A longtime student of hurricanes and their effects, Penland has often warned that the city is ill-prepared for a storm of Katrina's power.
"I had planned to leave," he said in a telephone interview. Then he told his wife he'd changed his mind. "I said to her, 'I want to stay.' She said, 'You're nuts. Call me every hour and let me know how you're doing.'"
Hundreds of thousands of New Orleans' 462,000 residents had left by yesterday afternoon.
"This place is a ghost town," Penland said.
Category 5 storms
It should be. Hurricane Katrina was a fearsome Category 5 storm on the Saffir-Simpson scale, capable of catastrophic damage.
Only three other Category 5 storms have made landfall in the United States since record-keeping began: An unnamed storm hit the Florida Keys on Labor Day in 1935, killing 409 people. Hurricane Camille struck the Mississippi coast in 1969, killing 259. And Andrew ravaged South Florida in 1992, killing 15 and leaving $26.5 billion in losses -- the costliest hurricane on record.
Category 5 storms have sustained winds in excess of 155 mph, enough to cause complete roof failures and some building failures. Mobile homes are demolished. Buildings within 500 yards of the shore and 15 feet of sea level suffer major damage to lower floors.
Katrina was intensifying, with peak sustained winds yesterday over 160 mph.
"This looks like the worst I've ever seen professionally for New Orleans," Penland said.
Atmospheric pressure in the hurricane's eye was 902 millibars (26.64 inches of mercury), the second-lowest barometric reading ever recorded in the United States after the Labor Day storm's 892 millibars.
A vulnerable city
New Orleans' vulnerability stems from several factors. First, the soil the city was built on has been settling for 300 years, and drainage for development has made it sink faster. It's still sinking by a third of an inch per year, and sea level is rising. Ships passing along the levee float yards above streets in the French Quarter.
Flood-control projects upstream have cut the flow of sediment, leaving the Mississippi Delta south of the city without natural replenishment.
"That natural buffer of marshes and barrier islands has diminished by 40 to 50 percent since the middle of the 20th century," Penland said. "Anyone who lives down there will tell you that [what were once considered] small storms have become big storms in the last several decades."
The city responded after 1910 by building a system of levees, floodgates, 22 pumping stations and 180 miles of open and buried canals. It is still being enhanced and enlarged, at a cost of hundreds of millions of dollars and with a goal of protecting the city from Category 3 storms.
New Orleans was pumping water yesterday from its drainage canals into Lake Ponchartrain to the north, making room for storm water. Heavy steel floodgates in the levees were closed and sandbagged, sealing off the roads that pass through them.
"If the rain rate exceeds 4 inches per hour, the pumps can't pump it out fast enough," Penland said. "The area inside the levy starts filling with rainwater." Katrina was expected to dump 5 to 10 inches of rain in New Orleans, with 15 inches in places.
The next threat is storm surge -- 18 to 22 feet of sea water pushed by the wind.
The levees along the Mississippi at New Orleans are 27 feet high. The greater risk lies along Lake Ponchartrain. Levees there are supposed to be 17 feet above sea level, Penland said, but subsidence has left some only 14 feet above sea level.
"Historically, the city has always flooded from Lake Ponchartrain," he said.
Hurricane Betsy in 1965 topped the levees in places and left 6 to 8 feet of water in the city. "People were driving boats in the streets of New Orleans," Penland recalled.
Betsy is the storm longtime residents always name as the worst in memory. It was a Category 3 hurricane when it struck 70 miles east of the city.
If the Ponchartrain levees are breached by Katrina, water will pour into the city. Under worst-case scenarios, it would flood and disable many of the city's pumps and rise 20 feet -- to the rooftops in many sections.
Disaster modeling suggests that the death toll from a Category 5 storm that floods the city could be in the tens of thousands.
"The people who couldn't leave are the poor, people who don't own cars, ... people in nursing homes," Penland said. Estimates of their numbers run to 100,000. Shelters cannot accommodate all of them.
What could happen
Survivors would return to an urban nightmare.
"Think of all the mixtures of chemicals and sewage, the whole storm brew," Penland said. Even in good weather, "every canal has its own pollution problems, with lead, human sewage and industrial chemicals."
Rescue crews and engineers would go in first to search for the dead and injured, to restart the pumps and install auxiliary pumps to drain the city. They might have to breach levees to let the water out, Penland said.
Property damage would be in the billions of dollars. Some buildings would collapse, falling amid huge piles of trash, storm debris, ruined appliances and other belongings thrown to the curb by returning residents.
Officials have contingency plans to relocate operations to a site north of Lake Ponchartrain until the city can be rebuilt. That could take years, in light of the shortages of labor and materials that have frustrated recovery from last year's storms in Florida.
The city's best hope, Penland said, would be a change in Katrina's path that would take it ashore 60 miles farther east.
"New Orleans would be spared if, all of a sudden, this storm turned toward the Biloxi-Mobile area," he said. While devastating to those communities, the turn would put New Orleans in the storm's northeast quadrant.
"It would still be windy, and we would lose power," he said. "But then the winds are blowing offshore and we don't get the water piling up in Lake Ponchartrain, against the city.
"If we take the hit west of the city, then it's a huge [storm] surge, coupled with the wind event and the rain," he said.
Yesterday, it wasn't clear which way Katrina would go. But Penland said he was ready.
"As a scientist interested in storm impacts and storm geology, I'm hoping for it," he confessed. "This one's for the city, and I think I've got enough smarts -- between the big house and the boat and the truck and several fellow scientists -- that we're going to go through it, and we'll learn a lot from it."
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