But slowly, residents and businesses began finding their way out to discover what was left.
Each company called itself lucky. All of their workers survived.
But some of them - like their companies - were left homeless.
At USMI, Dreyfus adopted an attitude that Katrina would not kill the firm his father started. Less than two weeks after the storm, the company found a new home in Gulfport, in a series of buildings originally intended for a boat storage business.
Employees dug out anything usable from their New Orleans site. They used a bulldozer to drag molds from nearby levees where they had been dumped by the storm. They retrieved from the muck and standing water 145 of 150 raydomes - covers for radar equipment - that had been ready to go before Katrina. And they also found 15-16 snakes per day.
``You had to look at the bright side of things, or you could get lost,'' Dreyfus said. ``Every time you got something done, it was a victory.
``One of my guys came back one day and said he wasn't able to find anything. I said, `Nothing?' and he said, `Well, I did find some chain.' `Well then,' I said, `you found some chain. We needed some chain. That's great.' ''
Oreck collaborated with Precision to track down molds left in the wreckage, wading in with boots and a Bobcat to pry them out of mud and damaged machines. They managed to find them all, and repair them all, though it was difficult.
Dickten & Masch took on the repairs for some of the tools.
``We'd open them, and water would just come pouring out,'' said Jesse Smith, business development manager. ``It's amazing what sewage and sea water can do to highly polished tool steel.''
At Oreck, Ross dodged downed trees and power lines a day after the storm to discover everything still fairly intact.
At First American - where Vice President Bob DePerro was on vacation in Italy - President Bill Bartlett loaded up a truck with relief supplies and generators and drove to Ocean Springs from First American's sister company in South Beloit, Ill. He set up a camp outside the building, where he could watch over the site and also distribute water and supplies to employees. He even made breakfast on a propane stove.
And employees were coming in - many of them anxious to find out if they still had jobs, then sticking around to help with the cleanup.
Oreck set up a temporary human resources office in the guard shack at the entrance to its property. From there the firm could track hours for people who were helping clean things up or just collect names and contact information so they would know how to reach workers once they had the power back on and were ready to relaunch production.
Firms that were still standing took quick action to clear off debris and patch holes. Engineers picked up downed limbs.
At Dickten & Masch, Phillips and his crew did hand counts of the work in progress to bring inventory numbers up to date. In the mold room, they packed up tools to ship out to working facilities to ensure customers still had a steady supply of parts.
First American sent tools to its facility in Illinois and never missed a delivery, DePerro said.
``We managed to pull that off with a skeleton crew,'' he said.
``These are really tough people,'' said Scott Campbell, plant manager for Wellman. ``Their homes were destroyed, and they're still showing up, working to restore the plant.''
DePerro asked one woman how she made out. She called herself ``blessed,'' he said.
``I said, `So your house is all right?' and she said, `Oh no, it's totally gone.' '' he said. ``Turns out she was living in her truck with her two brothers, and both of them had lost their homes as well - and she called herself `blessed.' ''
The aftermath of Katrina has shown just how tight the interdependent bonds are between employers and employees.
Each business working to rebuild needed its employees, but many of the employees were left homeless. Oreck estimates 35 percent of its 500-person workforce had homes either badly damaged or destroyed by the wind and water. Wellman estimates 20 percent of its 200 workers were left without homes.
Dreyfus and USMI not only had to deal with damaged housing but also had to persuade employees to move about 75 miles to a new location.
Even workers without the catastrophic devastation of a missing home faced obstacles. With no steady supply of power in some regions of Hattiesburg for weeks after the storm, gas stations were closed. Workers had no access to gasoline to get to and from work - even after power was restored at Dickten & Masch.
They also had hungry families and, if forced to choose, would spend eight hours a day standing in line to get groceries at one of the few open stores, rather than commit the time to work.
So manufacturers also became relief agencies.
Wellman put 24 trailers from the Federal Emergency Management Agency on its property to provide housing for workers - doing battle with federal regulations that the site not harm any endangered species.
``I told them, it's a gravel parking lot. What kind of endangered species do you think are living there?'' Campbell said.
The company pumped waste water into a tank - and arranged for the tank to be pumped out each day - so its workers had access to working toilets and showers long before the sewage lines were working.
Intralox set up its own FEMA trailer park on its property, while USMI brought in three- and four-bedroom trailers for its new Gulfport site.
Oreck bought 50 trailers and paid to place them at a campground near Gulfport.
``Oreckville'' became home to lab technician Larry Boggs and his wife for five months.
The storm had flooded their apartment, leaving behind an invasion of mold. The rooms weren't livable, but with no other choice, the couple sealed off all but one room with plastic film and tried to hold back the mold with bleach in an effort to have at least one room to call home.
Boggs said he wondered if it was worth the effort.
``I'm 50 years old,'' he said. ``How am I supposed to start over again?''
He was debating whether to give in and move back to Ohio where he had family and a job offer. He was handed a key to a trailer in Oreckville an hour after the company heard about his living conditions.
Last month, he and his wife bought a new house.
``I would not have been able to do that if it weren't for Oreckville,'' he said. ``Every month, the money I would have had to spend on rent or utilities went into the bank. My check from the Red Cross went into the bank. My check from FEMA went into the bank.
``If it had not been for Oreck, I would have packed up and gone back to Ohio.''
And companies stepped in with smaller efforts as well.
Dickten & Masch's corporate office in Nashotah, Wis., sent a trailer filled with relief supplies: bottled water, canned food, diapers, formula.
The interdependence also spread between customers and suppliers. In the overwhelming number of cases, parties helped one another. But there were exceptions.
Intralox's Paul Horton recounted how a major resin supplier, which he declined to identify, refused to ship resin to the firm's Harahan plant after the storm because it had not yet received payment for the materials from the molder.
An angry Intralox official promptly advised all in his company to avoid using any of that supplier's material in future products as soon as possible.
Most others were much more supportive. Dickten & Masch customer Kohler Co. - located in the same industrial park outside Hattiesburg - was ready to launch production of its engines but needed D&M to provide parts.
To help Dickten & Masch employees get the fuel they needed, Kohler arranged to share gasoline from a tanker truck sent for its own supply.
With power on and the company's water and sewer working, Dickten & Masch opened its showers and break rooms to employees' families, who had gone through a week of 97Ã¸ F heat with no access to air conditioning or baths.
``Your whole perspective has to be that your business is built around your people,'' Phillips said. ``You are your people, so taking care of your people becomes the No. 1 priority.''
Intralox brought in catered hot food - sometimes the only hot meals employees could get in the weeks after the storm.
In a sense, the job became a place of emotional refuge from the turmoil and destruction outside.
``It was some kind of normalcy,'' said David Lowry, production manager. ``When you're in the building, things are just as they've always been. People would joke around about how good it was coming to work because at home they've got 20 people crowded into one room.''
A week after Katrina hit, Dickten & Masch ran one shift and told workers to spread the word that they would launch full production the next day and that relief supplies and gas were on hand for everyone. Nearly everyone made it to work.
Oreck had power back nine days after the storm and began cycling on a few machines. Two weeks after Katrina, it relaunched full production.
Intralox began making its modular plastic conveyor-belt systems 11 days after Katrina. Fourteen days after the storm, it ran its first night shift, despite having to work around the city's curfew.
In the new Gulfport headquarters of USMI, work resumed three weeks after the storm, beginning with the hull on which Mejia completed structural work prior to the storm. At the end of March, its first wholly Mississippi-made boats went into service.
The impact of Katrina will not stop the growth of the plastics business along the Gulf Coast.
In the midst of the cleanup at MPT, Solvay announced its acquisition plan for the company, making it part of its Solvay Advanced Polymers unit. The letter of intent let employees know Solvay would not abandon them, Hearin said.
Wellman will have its latest expansion at the park operating during the second quarter of this year - only slightly behind schedule because of the hurricane.
Intralox is adding space and presses.
First American has been working to bring more business back into its Ocean Springs operation, but recently launched its first post-Katrina new contract, making the housing for a garage door opener.
And in Hattiesburg, USM is launching a specialized industrial park on its former golf course, with a special emphasis on new plastics companies that can take advantage of the support from the university and the polymer institute.
Disasters are not unique to the Gulf Coast, Horton said. A company on the West Coast could have to deal with the aftermath of an earthquake. There are tornadoes in the Midwest and floods all over. Maybe a storm cuts off the supply line. The biggest lesson out of Katrina has been that good people make a difference.
``You can plan all you want to, but when it comes to something of this magnitude, all you can really do is hire people who can think on their feet,'' Campbell said.