Firefighters lacked sufficient water.

Hydrants failed; stream couldn’t reach roof of blazing warehouse.

As multiple explosions and fire ripped through a Marietta chemical warehouse, firefighters ultimately could do little more than watch. They didn’t have enough water to fight the massive blaze.

The stream from a fire hose couldn’t reach the roof of the burning warehouse. Hydrants stopped working as water pressure dropped. Firefighters turned to using water from one of their trucks, to no avail.

In reports filed by the Marietta firefighters who fought the May 23 blaze, one engine company says its water supply was “extremely soft and intake pressure bordering on zero

the entire time during pumping operations. ... (Firefighters) lost pressure two more times during these operations, and when pressure returned it appeared to be lower than previously being received.”

Trucks from Dobbins Air Reserve Base and Lockheed Martin’s fire departments dumped several hundred gallons of fire suppression foam, but that also had limited success because of problems reaching the blaze.

Eventually, crews were pulled back and didn’t return for hours, after the fire had burned down to a manageable size.

The findings in the fire companies’ reports expose new concerns about vulnerabilities at the Amrep complex, which keeps volatile and toxic chemicals on its site and has had fires in years past. The size and configuration of the water mains in the area limited the amount of water that could be deployed, according to the reports, and early on supplies dwindled. And Amrep lacked its own water supply for firefighting, although that is an industry standard when a municipal water system isn’t adequate for the hazards that a company may face.

As a result, the reports indicate, firefighters narrowly avoided a catastrophe at the complex. As the fire burned for more than eight hours, other Amrep buildings with hazardous chemicals were endangered, and firefighters were worried that the blaze would spread to nearby businesses in the industrial area.

The reports describe harrowing scenes. At one point early on during the May 23 fire, with the water supply growing less stable and wind blowing toward one fire crew, it appeared that some firefighters could become trapped. They were pulled back to Marietta Industrial Boulevard.

But an Amrep employee told firefighters that if the fire spread to anoth- er building at the site, “he did not advise any units being located on Marietta Industrial.”

Amrep workers were allowed to go into one building at the complex to turn on a deluge system so water could cool pressurized tanks storing propellants. The worry was that fire reaching the tanks would create an even more dangerous conflagration. The reports don’t say what was in the tanks. But officials previously have said that pressurized tanks near the warehouse held heptane and butane, which burn explosively.

As it was, fire spread from the warehouse, which didn’t have sprinkler systems, to two tank trailers and pressure tanks on two sides of the warehouse, as well as to a nearby business, the report says. No information was available Friday on any damage to that business, at 978 Industrial Park Drive.

Ultimately, 75 to 100 firefighters from four departments fought the fire.

With water resources failing and multiple explosions, though, fire departments had to pull their crews back a half mile for their safety and focus on sparing other properties.

The reports don’t state what time the crews were pulled back but indicate they weren’t able to return for several hours.

Eventually, as the warehouse fire burned itself down, firefighters were able to go back. One of their tasks was to cool large vertical tanks outside the metal warehouse. An Amrep representative told them the tanks were not to exceed 120 degrees. But even after firefighters cooled the tanks for several hours, they were at 150 degrees.

Firefighters also found that a pile of 50-gallon drums was still smoldering and needed to be cooled off. And Amrep representatives found that leaks were coming from two large, upright tanks. The report doesn’t say what chemicals were in the tanks or how much they leaked before the company repaired them.

Officials with Zep Inc., Amrep’s parent company, did not respond to an AJC interview request.

Commander Tim Milligan with the Marietta Fire Department said firefighters everywhere deal with uncertain water supply for major fires. “We hook to a hydrant, and what we have is what we have,” he said.

Milligan also said that Amrep was up to code on fire safety.

National standards, however, make it the responsibility of the owner of an industrial site to determine how to get needed water, said Matt Klaus, a principal engineer with the National Fire Protection Association. If a municipal water system can supply enough flow per minute, for a stated duration, to deal with the hazards a company may face, the company can rely on that.

“If they don’t have the pressure and they don’t have the flow, it doesn’t mean the owner can say, ‘Well, I don’t have to do anything,’ ” Klaus said. The owner must supply that water, he said, and many store water in tanks on site.

Georgia has adopted the 2012 International Fire Code, which has a similar requirement, said Glenn Allen with the state Office of Insurance and Safety Fire Commissioner. But it says that policies of the jurisdiction determine the means by which water is supplied to a premises.

Amrep drew from the same water system that firefighters were using, Milligan said. The deluge and sprinkler system elsewhere on the site dumped 3,000 gallons of water per minute, while outside crews set up six “master streams,” sprays so powerful that firefighters can’t control them without some mechanical or hydraulic assist. They used 6,000 gallons a minute.

While there was water, Milligan said, “with a fire that size we need to flow copious amounts.”

Reports from some crews at the scene indicate water problems began early on.

The area near the Amrep plant has an adequate number of fire hydrants, and they are checked periodically to make sure there’s good flow, said Bob Snelson, Marietta water director. A 10-inch water line, put in about 25 years ago, feeds the Amrep area. “That’s a pretty large line in our system,” he said.

The Amrep plant, which produces aerosol automotive and cleaning products, has had two previous fires. A 1997 fire burned two workers, one of whom died about a month later; and a 1999 fire severely burned another employee.

When the fire last month started, alarms at the warehouse alerted the evening shift to get out quickly, Milligan said. When firefighters arrived shortly after 8 p.m., employees had evacuated, reports say. One was hospitalized after inhaling fumes, the reports say. The reports show that the fire was declared under control at 4:59 a.m.

The fire’s cause had not been determined, although fire officials say they have ruled out foul play or arson. The reports estimate losses at $20.5