James B. Nelson and Sarah Hauer

Milwaukee Journal Sentinel

Workers blasted the massive steel roof off the Bradley Center in spectacular fashion Sunday morning, leaving debris scattered in the street and a large dust cloud drifting in the air.

The loud, violent blast — actually a series of dozens of small simultaneous explosions — took place just after 9 a.m.

It was one of the most remarkable steps related to the closing of the Bradley Center, the Milwaukee Bucks' home for 30 years, and the opening of their $524 million Fiserv Forum next door.

The Bucks declared the controlled demolition a success.

"The Bradley Center roof structure removal went as planned," said Barry Baum, Bucks chief communications officer. "We are one major step closer to complete demolition."

Onlookers gathered on the street around the Bradley Center and on various downtown parking structures in anticipation of the demolition.

Two series of warning horns were issued before the detonation of explosives that ringed the interior roof and were strung along the rooftop. One warning came about 8:55 a.m. and the second came at 9.

Explosives set along the roof on the outside went off with flashes and loud concussions and the structure swiftly became a swirling cloud of dust and debris.

Some pieces of debris soared into the air, but, as planned, the bulk of the structure collapsed into and was contained by the old arena's structure.

Even for those who knew it was coming, the event was startling, sudden and violent. Onlookers felt the sidewalk shake and their clothes press against their bodies.

Debris carried by the wind rained onto West State and North 6th streets and a dark dust cloud drifted slowly toward the southwest past the Police Administration Building and MacArthur Square.

The operation blew a large hole through the wall high on the south side of the building. That wall of the building appeared cracked and damaged. Crews spent several hours late Sunday afternoon removing granite panels from that area that were dislodge by the blasts.

State Street will remained closed overnight and is expected to reopen Monday morning.

Crews are expected to further inspect the building in the morning.

Contractors and the Bucks have said "ancillary damage" to other parts of the Bradley Center – a structure already being demolished – is not a surprise with a roof removal operation.

Workers are expected to remove the granite panels in the damaged area later Sunday afternoon.

After the blasts, debris was scattered along State Street. Workers using sweeping machines patrolled surrounding streets.

Four windows were damaged at Historic Turner Hall across 4th Street from the Bradley Center atrium.

There were no other reports of other damage in the area.

A few dozen onlookers gathered near West Highland Avenue and Old World 3rd Street to catch the big bang.

Mark Mattes, who helped construct the Bradley Center, watched with his wife, Kelly. For him, it was a sign of changing times. The sidewalk shook as the roof fell into the arena and clouds of dust filled the sky.

"We were freaking out," said Katie Landry of Milwaukee, who came with her parents and boyfriend to watch.

"I have never seen anything like that before. I didn't think it was going to be that high, big and loud".

Chris Theis and Keith Brzozowski watched the explosion from the parking structure next to the Hyatt.

"It was over a lot faster than we thought it was going to happen," Theis said. "All of a sudden there was a big boom and then it was just gone." The longtime Bucks fans wanted to see the stadium come down.

"We saw a lot of cool stuff in that arena — playoff games, Bucks games, Admirals games," Brzozowski, of Waukesha, said. Next up for the fans: celebratory beers.

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Workers have spent months clawing apart the Bradley Center from the inside. That work will now move to the outside and accelerate in the months ahead.

In advance, the Bucks downplayed the roof demolition, in part to reduce the number of onlookers. In a news release, they simply said that the Bradley Center "roof structure will be removed" and made no mention of the use of explosives.

The Bucks want the Bradley Center site cleared as soon as possible so that it can be redeveloped. A hotel, grocery store and other ideas have been mentioned as possible new uses for the 7-acre site.

The roof was collapsed to make it easier for ironworkers to take apart the structure, without having to work 100 feet in the air.

Fiserv Forum opened in late summer. Demolition of the Bradley Center is expected to be completed this summer.

"I've been in the Bradley Center many times and work on the bar on the corner (Pub Club)," said Steven Rosenberg of Brookfield, who watched from along Highland Avenue.

"I figured to see something so close to us, a piece of Milwaukee history, I kind of wanted to see it come down.

"It was a lot louder than I thought it would be."