CHICAGO — A water tank that toppled from the top of a landmark eight-story building near Diversey Harbor Wednesday morning injured three people, one critically, and rattled a city that has worked to preserve the wooden rooftop structures.
It wasn’t clear what caused the tank — one of fewer than 200 left in the city — to fall from the 120-year-old Brewster building. Neighbors and witnesses described hearing a loud roar as the tank crashed to the ground, spewing a wave of water and debris.
The most seriously injured was a woman in her 30s who was hit by splintered pieces of wood. Officials said she is expected to recover.
Once a key part of firefighting technology but now cherished mostly for their gritty architectural charm, water tanks are seen by many as a symbol of rebirth and resilience after the Great Chicago Fire in 1871. The stout silhouettes are such an iconic feature of the skyline that measures have been taken to preserve those that remain.
The Brewster’s black wooden water tower, about 8 feet in diameter and 10 to 12 feet tall fell off the northwest corner of the building shortly before 10 a.m.
Kathy Rawley was walking nearby when she heard shrieks behind her and turned around to see the tank, which could hold between 500 and 600 cubic feet of water, fall to the ground.
“It looked like a tidal wave, because water and debris shot everywhere,” Rawley said. “It was the scariest thing I’ve ever seen.”
An investigation into what happened will be led by the city’s Department of Buildings, said department spokesman Larry Langford.
“Was any maintenance done recently? Did anyone check the mounts recently? Obviously the wind didn’t blow it over,” Langford said.
Water tanks are inspected every five years, in conjunction with inspections of fire escapes, said buildings department spokesman Bill McCaffrey. Officials will discuss whether the city should initiate an immediate inspection of all existing water tanks in response to Wednesday’s incident, McCaffrey said.
Langford said the age of the structure is not necessarily a factor.
“The building’s 120 years old and it’s not falling apart. Age alone isn’t an indicator of longevity; it’s a matter of upkeep.”
Wooden water tanks rarely fall, but when they do, the cause is usually a failure by the support structure holding the tank above the roof, said Andy Rosenwach, manager of Rosenwach Tank Co., which builds and maintains rooftop tanks in New York City.
“If you don’t monitor the condition of the steel … you could have steel that’s becoming like tissue paper, and it becomes a very serious situation,” said Rosenwach, who spoke in general terms and not about what happened in Chicago. “Nothing’s dangerous as long as it’s maintained.”
Tanks with support systems that aren’t properly maintained are “timebombs that are ready to go,” he said.
Rosenwach said he recalls only one or two similar incidents in New York City since he began working in the business about 40 years ago, and he said he did not remember any injuries being reported.
Records posted on the city of Chicago’s web site indicate that the Brewster building was cited in 2010 for code violations that included misplaced steel bands around the water tank, and was ordered to submit a structural engineering report about the water tank.
McCaffrey said the ensuing report “deemed that the water tank and its support structure were in a safe condition.”
“This building has undergone a number of inspections in 2013 and in previous years, and while there have been building code violations, the number and extent of violations do not suggest that this building is neglected or poorly maintained,” McCaffrey said.
The building’s property manager did not respond to requests for comment.
Rosenwach said that while some modern-day tanks are made of steel, many are still made of wood, just like they were more than a century ago, because wood serves as natural insulation and becomes watertight as it is saturated by water.
Some tanks supply water for fire suppression only, while others supply water for both fire suppression and household use, he said. At the Brewster, the tank was still in use and provided water for residents, Langford said.
At one time there were thousands of water tanks in the city, but the need for them dwindled with the advent of electric-powered water pumps. As late as the mid 1990s, there were still 373 wooden tanks around the city. By 2006, the city estimated that only 178 were left and the City Council voted to make it harder for building owners to tear them down.
The 2006 ordinance imposes a delay of up to 90 days on demolition permits for rooftop water tanks so that the Department of Housing and Economic Development can consider ways to preserve the tanks.
Since then, 23 tanks have been demolished, McCaffrey said. He said there are currently “more than 150 water towers on rooftops throughout the city that are examined as part of routine inspections.”
