Hundreds of posts surrounding the new Milwaukee Bucks arena aim to prevent terror attacks

The least-noticed feature of the new Milwaukee Bucks arena might be a line of posts that runs along the north side of the massive structure.

They're called "bollards" and some will include decorative lighting. Yet they all serve the same serious purpose — protecting the $524 million building from a terrorist attack with a vehicle.

The posts are anchored in a deep trench and are the same kinds of structure used in other high-profile settings such as Times Square in New York City, said Greg Davidson, project manager for Calpipe Security Bollards.

The California company has worked with the NBA and the Bucks along with the project’s landscape architects, civil engineers, designer and contractor, said Calpipe spokeswoman Sierra Griffin.

The Department of Homeland Security offered recommendations to the NBA that factored into the arena work, Davidson said.

The demand for bollards jumped following the Sept. 11, 2001, terror attacks when governments took steps to better fortify public buildings and embassies, said Rob Reiter, Calpipe’s chief security consultant.

Another sharp uptick came last year following a string of attacks in Europe where terrorists plowed vehicles into crowds of people.

For the Bucks project, about 200 bollards will circle the arena itself, and another 100 to 200 more will be installed around the plaza and entertainment block outside the east entrance of the facility.

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The bollards are designed to be protective while also providing landscape lighting.

"The challenge is how do we meld those two things," Davidson said.

The result is bollards that blend with the building and its surroundings with "a real understated look," Davidson said. "They don't want to have anything that looks too intrusive."

The most important part of the bollards isn't visible. The posts are anchored in concrete and steel rebar 5 feet below the surface. The steel on the posts is an inch thick and the posts are 10 inches in diameter and filled with concrete.

In some facilities, the bollards are engineered so they can be retracted into the ground to accommodate special events.

The devices are designed to withstand the impact and stop a 15,000-pound vehicle traveling at 50 miles per hour, Davidson said.

The company's bollards are also found at big stores such as Walmart or gun shops to deter "crash and grab" thieves, he said.

Davidson estimated that the bollard business is a $500-million industry in the U.S.

At one time there were three or four companies making the devices and now there are 20, he said. In business 20 years, Calpipe is the second largest bollard-maker, he said.

"We certainly are in growth mode, " Davidson said.