Posted: Jun 29, 2011 10:40 PM by Maddie Garrett
Updated: Jun 30, 2011 3:35 PM
New numbers released by the National Oceanic and Atmospheric Administration suggest some parts of Lafayette Parish are sinking.
But at what rate and what this means for residents is up for debate.
Paul Miers, a civil engineer in Lafayette, said an area from the Mall of Acadiana through Scott and Maurice has sunk as much as 18 inches due to subsidence. Subsidence is a gradual settlement of the earth's surface due to techtonic plates moving below, and Miers said it could mean trouble for residents.
Tom Carroll, the Director and head engineer for Lafayette Public Works, has been following the effects subsidence for years. He said he thinks some of the numbers have been exaggerated.
"If the whole earth's surface is moving, everything is pretty much moving at some at least pro-rated rate, maybe more right here than right there. But it's just going to be a very slow, gradual effect," said Carroll.
The problem is that until 2006, elevation bench marks weren't measured very accurately, so it's hard to determine just how much subsidence has taken place. But Miers said recent data from NOAA gives us a general idea.
"There's some points that are moving a quarter-inch a year, and it's verified over a two or three year period," said Miers.
Miers said that some areas in Lafayette have sunk about 18 inches since the 1902's. And this could mean problems for residents in flood zones.
"It's important that people understand that there are places that are less elevation than what they were assumed to be six or seven years ago because the numbers have changed," said Miers.
On the other hand, Carroll said it's not subsidence that's effecting flood maps, but simply FEMA's new technology in updating elevations.
"In Lafayette we even went to the extent to get detailed studies done in many of our channels, to where subsidence really had no bearing, no relation to what was done by FEMA," explaiend Carroll.
Subsidence is something that takes place all the way from New Orleans, to Beaumont and even to Houston. Carroll said it's something to keep an eye on for Lafayette in years to come.
"We're kind of in a wait and see mode to see exactly what the impact's going to be, but I don't think there's been any impact on our facilities yet," said Carroll.