How would local transportation be affected if a metropolitan area experienced 140 million miles of additional heavy traffic in a 28-month period due to an explosive construction boom or a major disaster? New Orleans is about to find out.

The U.S. Army Corps of Engineers and state and city officials may be writing a primer on how to manage that kind of scenario. “They certainly had traffic impact with the Big Dig and the cleanup after the destruction of the Twin Towers, but never has a whole city been so affected by a construction project,” says Gib Owen, the Corps’ New Orleans District chief of ecological planning and restoration. “This will impact everybody.”

Photo: Tom Sawyer/ENR

Borrow trucks line up to support construction on a New Orleans levee.

In 2009, the Corps will award about 100 construction contracts worth $3.2 billion in the $14.3-billion push to bring the Greater New Orleans Hurricane and Storm Damage Risk Reduction System to “100 year” levels of protection by 2011. Contractors will haul 29 million cu yd of borrow, 822,000 tons of steel and 972,000 cu yd of concrete. “The scope at its peak is approximately 8,800 daily deliveries of borrow, 135 daily deliveries of steel and 130 daily deliveries of concrete,” says Col. Alvin Lee, commander of the Corps’ New Orleans District.

In a normal year, the five-parish area south of Lake Pontchartrain has an average of about 21 million miles of daily traffic, says Jeff Roesel, director of planning for the Regional Planning Commission of Southeast Louisiana. The additional 140 million miles does not include other construction traffic hauling aggregate over the Lake Pontchartrain Causeway from St. Tammany Parish to the north, transportation of construction workers and other support activities or the hauling of 30 million cu yd of levee material in Plaquemines Parish, which begins after the storm-protection work’s estimated traffic peaks. The Louisiana Dept. of Transportation and Development estimates there also will be up to $400 million of unrelated transportation construction under way at the same time.

The Corps brainstormed with state and local officials on July 30 on how to mitigate the traffic impact. The Corps plans to provide details on construction and traffic congestion via local media, the Web, Facebook and Twitter. It also hired a traffic engineer and plans to embed personnel in the Louisiana Dept. of Transportation and Development’s new traffic-control center to provide real-time signal coordination in areas with heavy traffic.

Bruce Terrell, chief of the New Orleans District’s construction division, says contractors will pick their own delivery routes, but the Corps and local authorities will manage traffic flow and may establish turn lanes or install message boards.

The Corps also will team up with environmental agencies and DOTD to monitor emissions and road wear and tear, respectively.