This Corps of Engineers publication from June, 2003 describes what was recommended to protect New Orleans against flooding from a large hurricane.

...Engineers determined that the levees bordering the Mississippi River as it passes through the city were sufficient to withstand any surge produced by an SPH. So the idea was to create a rough semicircle of hurricane levees along the boundary of the lake that would start at the Mississippi River levee west of New Orleans and end at a point to the east of the city. Additionally, levees, floodwalls, or both would have to be constructed around each of the area’s drainage canals, as well as around bridges crossing those canals and around the pump stations emptying into the lake.

As the program continued, one project spiraled into another. In 1986 Congress authorized the Corps to build a system of levees around the southern half of the city, also forming a rough semicircle extending to and from the Mississippi River levees. In the mid-1990s Congress continued to expand the southern protection zone, requiring a total of about 65 mi (105 km) of levees and thereby protecting tens of thousands of homes.

"People live their entire lives in an area that is below sea level and it just becomes a fact of life,” says Al Naomi, the project manager for all of the Corps’s hurricane protection levees in southeastern Louisiana. "They just keep taxing themselves for drainage and levee improvements to make sure they can stay here. Staying dry is very important in this city. People will vote for improving drainage before they’ll vote for improving schools."

Naomi was in high school when the Corps began constructing the levees bordering Lake Pontchartrain. And he will probably retire long before the barriers around the southern part of the city are completed—in 2018 if all goes as expected. In the next few years he will also oversee the beginnings of three Corps levees that are now being constructed around less populated areas outside of New Orleans: Venice, Grand Isle, and Larose. About $900 million has already been spent on Louisiana’s hurricane protection program, and before the current projects are complete more than $1.4 billion will be required.

In 1999 the Corps was authorized by Congress to study the feasibility of various proposals for protecting the city against such devastating storms. An obvious possibility would be to raise the current levees to a height deemed acceptable by an AdCirc analysis. That, however, would also require widening the levees, which may not be possible in many areas because of the proximity of homes. Among other alternatives, Naomi will investigate the possibility of creating an immense wall between Lake Pontchartrain and the gulf to keep water out of the lake during a severe storm. Such a project would involve constructing massive floodgates at the Rigolets and Chef Menteur passes, where storm surge would enter the lake.

According to Naomi, any concerted effort to protect the city from a storm of category 4 or 5 will probably take 30 years to complete. And the feasibility study alone for such an effort will cost as much as $8 million. Even though Congress has authorized the feasibility study, funding has not yet been appropriated. When funds are made available, the study will take about six years to complete. "That’s a lot of time to get the study before Congress," Naomi admits. "Hopefully we won’t have a major storm before then."

Boldface mine, pointing out some dates and schedules. Add six years to 1999, and what do you get for the year the STUDY would have been completed when or if funding was provided? Names like the "Coast 2050 Plan" speak for themselves. We aren't talking short-term solutions, here.

To make it clear, if Bush had supplied every nickel the Corps of Engineers had asked for from the day he was first inaugurated, we would still have been years away from completion of the levees when Katrina struck. The idea that the development of wetlands that has occurred since 2003 would have made any difference is utterly ridiculous. Blumenthal is full of shit, to put it mildly, and it wouldn't be the first time.