When Hurricane Katrina struck New Orleans on Aug. 29, 2005, more than 50 levees and flood walls gave way, sending tens of billions of gallons of water roaring into the city, causing horrific death and destruction.
Could that happen in another city protected by levees and flood walls — Hartford?
It seems unthinkable, but to officials who've been meeting on it for several months, it isn't. The levees and flood walls protecting Hartford and East Hartford from Connecticut River flooding are old and in need of repair. As in New Orleans, the levees in some places are being undermined by seepage.
Although Hartford and East Hartford have undertaken levee repairs in recent years, there are still serious deficiencies that must be addressed. Engineers have laid out a project list that would cost about $100 million. U.S. Rep. John Larson, who has convened meetings with local officials and the U.S. Army Corps of Engineers, said he will ask Congress for the money. "We're going full bore on this," he said.
It's a lot of money, but it is a pittance compared to the costs if the levees fail.
Hartford was hit by massive floods twice in the 1930s. The Great Flood of 1936, a 500-year-flood, inundated much of the city, left 14,000 residents homeless and caused millions of dollars in property damage. The 1938 flood was almost as bad.
That prompted the construction of one of the most elaborate flood-protection systems on the East Coast, consisting of seven miles of levees (earthen embankments and concrete flood walls), six storm-water pump stations and more than five miles of major underground conduits on the Hartford side; and four miles of levees, three pump stations and other equipment on the East Hartford side.
The system, mostly built between 1938 and 1944, has worked well and spared both communities from major river flooding. But it is now up to 75 years old, and maintenance was sometimes deferred over the years. There has been development along the dikes on both sides of the river, including highway construction and the lowering of part of I-91 on the Hartford side. The hydraulics of the river have changed.
In recent years, both Hartford and East Hartford have invested millions of dollars in improvements to the levee system to satisfy mandates from FEMA and the U.S. Army Corps of Engineers, which both have levee oversight responsibility. Both municipalities went through the arduous process of getting a FEMA letter of accreditation for the system, important because without it, those in the levee-protected area — about 20 percent of Hartford — would have to buy flood insurance, and public investment in the area would be curtailed.
But accreditation came with caveats that major capital improvements be made. The FEMA certification was that the system could withstand a 100-year flood. The Corps of Engineers wants the system brought back to its initial design capacity, which was to withstand a slightly-greater-than-500-year flood. In the era of climate change, that would be wise.
The list of projects includes the mitigation of seepage under flood walls and the upgrading or replacement of conduits, pump stations and toe drains. It all must be done; another Katrina lesson is that all components of a flood protection system must function for the system to work.
If the levees failed in a major storm, the flooding would cause loss of life and incapacitate the downtown business district, the Interstate 91 and 84 interchange, the sewage treatment plant, the trash-to-energy plant, Brainard Regional Airport, etc.
The two municipalities already have borrowed tens of millions to make levee repairs and don't have another $100 million. Mr. Larson believes it is a federal responsibility, and said it could help demonstrate the multiple benefits of putting the country back to work repairing its infrastructure.
Levee maintenance is essential. As East Hartford Public Works Director Tim Bockus put it,"You can't not do it."Copyright © 2015, CT Now