When the 2011 hurricane begins on June 1, one hundred per-cent of the Greater New Orleans Hurricane and Storm Damage Risk Reduction System will defend against a 100-year storm surge: 97% of the perimeter system will be constructed to 100-year design criteria; 2% of the system will have Engineered Interim Closure Structures in place; and 1% of the system will have Engineered Construction Closures on site to close gaps should a hurricane threaten the area. With hurricane risk reduction keeping storm surges out and SELA projects pumping rainfall out, the goal is to keep South- east Louisiana on dry ground this hurricane season.
From the Jefferson/St. Charles Parish line to the Intracoastal Waterway in Belle Chasse, projects are under way that will provide permanent, or in a few cases, interim risk reduction from storm surges. For example:
1 - A new West Return Floodwall on the St. Charles/Jefferson Parish line will not be completed until December 2011, but the original floodwall, strengthened with earthen berms, will provide interim storm defense this hurricane season.
Jefferson Parish Perimeter Levee Construction
2 - Along Lake Pontchartrain in East Jefferson Parish, all 9.1 miles of perimeter levees have been raised to the 100-year elevation. The new breakwaters at Bonnabel and Duncan pump stations, along with the existing floodwalls, provide a 100-year level of risk reduction. The new fronting protection being constructed at Elmwood and Suburban pump stations will not be complete until late in the 2011 hurricane season but engineered interim measures are being placed to defend against the 100-year storm surge.
3 - Floodwall work at the Causeway Bridge is currently under way and scheduled for completion in January 2012. The existing floodwall, reinforced by sandbags across the bridge decks to minimize wave overtopping, will provide 100-year storm defense for this year’s hurricane season.
Jefferson Parish Levee Construction Work
4 - On the West Bank, substantial completion of the massive West Closure Complex restricts storm surge from entering the Algiers and Harvey Canals. Additional improvements to the detention basin are required to finish the enhanced West Bank project. The Harvey Canal Floodgate, a major risk reduction feature, was completed in 2007. South of the floodgate, approximately 2.5 miles of floodwalls and one mile of levee have been constructed along the Harvey Canal, and the Hero Pump Station Fronting Protection is now complete. The industrial reach along the Algiers Canal has been raised and a stability berm to reinforce the levee is under construction. Three other construction contracts have been awarded to raise levees and increase levee stability along the remaining Algiers Canal levees. Other ongoing construction along the Algiers Canal includes the construction of floodgates and pump station fronting protection in three parishes.
5 - Although it won’t be finally completed until late 2012, the Corps is driving hard to have the most important flood protection features of the massive West Closure Complex in place by June 1. The complex includes a 225-foot sector gated structure, floodwalls, foreshore protection, five sluice gates, an earthen levee, and the largest pump station in the world.
Construction of the 225 foot sector Gate and Pump Station
6 - To protect the Company Canal and Bayou Segnette area from 100-year storm surges, the Corps is building a floodgate/levee/pump station complex, along with fronting protection at the Segnette Pump Stations. Levee enlargement work and fronting protection for the Lake Cataouatche Pump Station will be complete by June 1, as will a floodwall being replaced at Bayou Segnette State Park. An operable interim closure gate across Company Canal is currently providing 100-year risk reduction until that portion of the project can be completed.
7 - The Western Tie-In, a project designed to link the HSDRRS with the Mississippi River Levee, is under construction. By June 1, Engineered Construction Closures will be in place along Highway 90 and at railroad crossings to defend against a 100-year storm event. There will be three closings and one Engineered Interim Closure measure along Bayou Verret.