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    Credit: City of Gulfport

    Dark blue represents Hurricane Katrina's storm surge throughout the 64-square-mile city of Gulfport, Miss. A railroad line on an elevated berm that travels the length of the city and parallels the coastline from 1/4- to 3/4-mile inland served as a makeshift, though only slightly effective, levee.

After hitting Gulfport, Miss., on the morning of Mon., Aug. 29, 2005, Hurricane Katrina hammered the Mississippi coastline for more than 17 hours. Winds of up to 150 mph and storm surge levels of up to 30 feet destroyed nearly all structures within a 1/2-mile radius of the city.

Cleanup and rebuilding efforts are still taking place

Being prepared for a natural disaster the size of a category-5 hurricane sounds like a paradox, but from an information services standpoint, Gulfport's public works department was as prepared as possible. In 2002, in an effort to improve its asset and work management system, the operation supplemented ArcGIS with Azteca System Inc.'sGIS-centric Cityworks software program.

"Katrina destroyed our infrastructure - water, sewer, storm drain - for about three to four blocks inland, all along our beachfront," says Ron Smith, assistant public works director for the city of 30,000 residents. "All the utilities that linked to all the businesses and homes in that area were completely wiped out." The recovery effort began midstorm amid chaos as workers labored to plug and cap holes and shut off valves to keep water tanks from completely draining. Much of the damaged lines were underwater or beneath rubble and debris, making their exact location difficult to pinpoint and access. The city's normal water pressure of 60 psi fell as low as 25 psi for a week after the storm hit land. In addition to the water system, debris had clogged and crippled the storm drain and sewer system, which only intensified flooding. "You couldn't have packed concrete into our storm drains any tighter," says Smith.

The GIS server, which had been taken offline and stored in a secure area as Hurricane Katrina approached, was back up and running five days after the storm had passed. In the meantime, though, public works couldn't give cleanup crews accurate location coordinates for its assets; and debris-removal contractors further destroyed waterlines, valves, gas meters, and fire hydrants with bulldozers and excavators. Each time a waterline or fire hydrant was broken, water pressure would once again drop and public works crews would be dispatched to make the necessary repairs. The problem ended when the department was able to provide contractors with GIS-based printed maps marking the locations of fire hydrants, valves, and waterlines.

"We immediately started entering and documenting all the waterline breaks, plugs, and caps," says Smith. "We were also very busy tracking, mapping, and documenting the damage done after the storm." With crews working around the clock, most major roads were cleared and water pressure was restored to 90% of the city within a week. The other 10% were damaged beyond repair. Public works lifted a "boil water" notice three weeks after the storm; by week four the sewer system and traffic signals were working. As cleanup and rebuilding progressed, it was determined that nearly 15,000 traffic signs needed to be replaced. The geodatabase helped managers justify replacement by identifying the attributes and original locations of the destroyed signs.

But that was a small task compared to the estimated 3 million cubic yards of debris that needed clearing from Gulfport's coastal area and the 50 miles of water, sewer, and drainage pipe that needed to be replaced. Early on, EPA had representatives in Gulfport to advise on environmental issues and concerns. Seven months into the recovery process, EPA brought in a team to analyze the storm's entire impact on infrastructure.

"We used our asset management system to show them all the areas in our lines that were destroyed and had water leaks and damage and where they had been fixed or needed repairs," says Smith. "When we looked at all the points on the map, it looked like a shotgun blast. From our GIS maps, the EPA representatives determined that there was no way we could just repair it. They recommended that we replace all our lines near the beach."

The GIS-centric software allowed Smith and his colleagues to generate a highly detailed map of the entire scope of damages. Based on the analysis, EPA recommended that the department receive funding to rebuild water, sewer, and storm drain infrastructure, which would necessitate new sidewalks, curbs, guttering, and asphalt roadwork, near the coastline. Ultimately, the Federal Emergency Management Agency (FEMA) approved the multiyear project at an estimated overall cost of $100 million.

EPA's endorsement was a huge relief because, before the analysis, Gulfport was having difficulty justifying the need for federal relief.The system also served as expert witness, helping residents file insurance claims and receive federal funding for damage done to private property. The mapping functionality in its GIS was used to generate lists and identify the addresses that fell within flooded areas. Because accurate data for infrastructure assets existed before the hurricane, the system has helped show contractors and planners where new valves, hydrants, waterlines, and meters should be placed. "In construction, nothing ever goes exactly the way that you want it to go," says Smith. "Something always needs to be rerouted or redesigned, and when that happens, its new location, size, and material type is getting plotted."

- Matt Freeman mfreeman@esri.com ) is a writer for ESRI in Redlands, Calif.