reflooded part of eastern New Orleans. November and December The Corps continued work into November and December 2005 on filling the breaches in the London Avenue and 17th Street canals, as water continued to seep through the temporary breach repairs into streets. Completion of temporary repairs By January 2006, the Army Corps of Engineers announced that temporary repairs of the Industrial, London Avenue, and 17th Street Canals had been finished. A project for more permanent repairs started. Future improvements In January 2007, the Army Corps of Engineers, after having visited the extensive "Delta Works" levee system in the Netherlands, awarded a $150 million contract to a group of Dutch engineering companies for the evaluation, design and construction management of levees and floodwalls, special closure structures for protection of the communities adjacent to the Inner Harbor Navigation Canal, major pumping facilities and planning studies for improved levels of flood protection for New Orleans and southern Louisiana. The Delta Works are a series of constructions built between 1953 and 1997 in the southwest of the Netherlands to protect a large area of land around the Rhine-Meuse-Scheldt delta from the sea. The works consist of dams, sluices, locks, levees, and storm surge barriers. The works were initiated after the North Sea flood of 1953 in which 2,170 people were killed. Since Katrina, the US, through the Army Corps of Engineers, has made a $14.45 billion investment in the area around New Orleans. Some of the projects include: The world's largest water pump station (Gulf Intracoastal Waterway West Closure Complex) which can pump per minute and will cost $1 billion. Hundreds of levee and pump station improvements. The IHNC Lake Borgne Surge Barrier, the longest storm surge barrier in the United States The Seabrook Floodgate, a floodgate at the connection of Lake Pontchartrain with the Industrial Canal Bridges, Roadways, and Railways Approximately 45 bridges were damaged by some aspect of the hurricane. Several major bridges were among the worst damaged, with the I-10 Twin Span Bridge as the most catastrophic failure with over 470 spans separated from their supports and nearly 65 fallen completely into the water. Other vital bridges damaged enough to impede traffic included the Pontchartrain Causeway, St. Louis Bay Bridge, and Biloxi Bay Bridge. Mississippi railways and roads, when not affected by bridge collapsing, were disrupted due to heavy debris. Removal costs are estimated at $200 million for that area. Damage