There has been good news over the past 24 hours for Baton Rouge and New Orleans.
Diversion of rising Mississippi River waters though the Morganza Spillway northwest of the cities and into the Atchafalaya River basin appears to have helped lower the chances that the urban areas will be swamped.
Major tourist attractions and historic sites seem likely to be spared, including a necklace of Antebellum-era plantations along the Great River Road. A few, including the white-pillared Nottoway Plantation, posted assurances of their dryness online, along with photos of nearby levees keeping water contained.
But what's good for Plantation Country and the Big Easy has required sacrifice in the rural, swampy area west of the Mississippi. And the toll includes not just homes, displaced residents and the swamping of vast acres of cropland.
It also includes historic and archaeological sites that will likely be underwater for weeks to come. And state officials are bracing for damage that the diverted water could wreak on those sites.
Indian Village and War Sites
"The primary concern for damage is relatively close to the spillway and near the channels, where silt could harm sites," says Chip McGinzie, Louisiana's state archaeologist.
Louisiana's Historic Preservation office has also been compiling a list of which of the state's more than 1,200 sites listed on the National Register of Historic Places — ranging from buildings to designated districts and landscapes — may be affected.
State officials, however, have noted that the area affected by floodwaters released through the spillway is sparsely populated and, while important, is not chockablock with properties on the National Register. The Morganza release is the first in 38 years.
The vast majority of the area has not been surveyed, McGinzie says, and there's little development in the basin because, bottom line, it's a swamp.
He estimates that there are about 530 known archaeological sites, ranging from a quarter-acre to up to about 10 acres, in the area where floodwaters will be diverted.
Sites affected include remnants of a Civil War fort in Butte La Rose, as well as scores of Native American burial mounds and campsites, and early Acadian campsites. Many of the Indian campsites, he says, are represented by what are known as shell middens, archaeological sites that contain discarded shells and other detritus of domestic life.
There are likely thousands more such sites in the areas not surveyed.
The Civil War fort, where earthen embankments are still visible on the ground, will certainly be inundated, officials say.
Fort Burton, which once stood at the site, was captured by the Union Army in 1863. It was described by one Union soldier at the time as a "grand rendezvous of mosquitoes, fleas, woodticks, lice, lizards, frogs, snakes, alligators, fever bacteria, dysentery microbes, and every conceivable type of malarial poison."
But the area being intentionally flooded is no stranger to floods.
"The Atchafalaya River used to flood annually — that's what rivers do," McGinzie said.
And the drowning of archaeological sites, he says, doesn't necessarily hurt them; it often protects them by burying them in silt.
Officials say they simply don't know what they'll find when the floodwaters recede: The interesting part, they say, is going to come afterward, when they start assessing the effect.
On The Register
State historians have identified two sites on the National Register that will — or could — be affected by the spillway release: a lighthouse and a Civil War battlefield.
"Fortunately, we don't have too many properties that could be impacted," says Jacques Berry, spokesman for Lt. Gov. Jay Dardenne. "It's not an area that has a lot of anything other than wildlife and flora."
The historic Southwest Reef lighthouse on the banks of the Atchafalaya River in Berwick is likely to be affected by the diversion of floodwaters. The circa-1856 structure, which once stood in Atchafalaya Bay, was moved upriver in 1987.
There are more historic structures in next-door Terrebonne Parish, where backwater flooding is a concern, Berry says, but most are surrounded by levees.
Rising water is also a concern at the Port Hudson battlefield, Berry says, the National Historic site of an 1863 Civil War battle, part of the key struggle for control of the Mississippi River.
Located upriver from Baton Rouge, the site now includes the battlefield and cemetery, as well as hiking. Those trails, in the lower part of the site, have already been closed.
Though nothing is certain, Berry says that officials don't expect the battlefield, now the site of Civil War reenactments, to go underwater — "especially with the river cresting earlier than expected."
Early reports that historic floodwaters carried the potential to inundate tourist attractions and cities spooked visitors.
And that has alarmed those in the state's tourism industry.
"A lot of people have heard that Cajun country is underwater, and that's not the case," says Lauren Bodin of the Louisiana Travel Promotion Association, a member organization.
"The Morganza Spillway hasn't been opened since 1973, so it's hard to predict what will happen — but we're doing business here as usual," she said.
A conference call the association held with many members the day before the Army Corps of Engineers began opening spillway doors revealed anger at the media, and a handful of reports of expectations of some backwater flooding.
Some companies providing swamp tours have had to adjust because high waters prevented them from getting into tributaries, Bodin says, and there have been scattered reports of hotels closing.
"But not many had to take precautionary measures," she says.
The federal government doesn't typically take lightly actions or activities that have the potential to affect historic sites.
Typically, an action such as the spillway release would, under federal law, have required a review of the action's effect on historic and cultural sites — and that can take up to 30 days, says Caroline Hall at the federal Advisory Council on Historic Preservation.
In emergencies, however, the review process can be bypassed if there's a demonstrated threat to human health, life and safety.
"We obviously care about the protection of historic properties," Hall says. "But the importance of health and safely far outweighs other considerations.
"It's a reality that these types of laws are very important under normal circumstances," she says. "These are not normal circumstances."
Federal officials will get involved again after the water recedes, and once local officials determine what needs to be done to stabilize historic properties, or to demolish them, if damage dictates.
The good news is that floodwaters released through the spillway are moving south much more slowly than expected, according to Berry, of the lieutenant governor's office.
The Army Corps has also said they'd likely open no more than 25 percent of the 125 gates at the Morganza Spillway, Berry says, meaning volume and velocity of water will likely be far less than once anticipated.
The area is technically in a drought, so the land is absorbing more water. And, Berry says, the proliferation of crawfish farms and vegetation is also slowing the flow.
"The water will get there, but it's not moving as quickly as expected," he said — a better case scenario than most anyone was envisioning just a handful of days ago. Copyright 2011 National Public Radio. To see more, visit http://www.npr.org/.