A tradition that started 60 years ago in downtown Denver and became commonplace in intersections around the world is about to end in its city of origin as city traffic engineers give last call to the “Barnes Dance.”

The maneuver that stops traffic in all directions and gives pedestrians unfettered access — allowing people to briefly dance in the streets as they meet in the middle and dodge and weave to get by — will end May 14 as the city reconfigures its traffic signals.

“It’s going to definitely make it less convenient to get from point A to B,” said Pierre Bruce, who works as a software engineer downtown and was standing at the corner of 16th and Stout streets.

The move is necessary because of transportation changes that will affect downtown beginning next month, including longer Regional Transportation District light-rail trains and longer crosswalk intervals.

Also, signal cycles — the time it takes for a signal to change from green to yellow to red and back to green again — also will be increased to 90 seconds from the current 75 seconds.

Any change in modes of transportation in the tightly controlled downtown core ripples through the system, creating an interesting dilemma for engineers who had to use high- powered computers to figure out how to make it all work.

“Our goal is to balance everything,” said Brian Mitchell, Denver’s chief traffic engineer. “We want downtown Denver to be a multimodal system for pedestrians, cars, transit and bicycles. We want all of them to be part of the system.”

The “Barnes Dance,” or more specifically, the ability of pedestrians to cross diagonally in 45 of downtown’s 235 intersections, had to be sacrificed, Mitchell said.

The city will maintain “all- walk” signal operations but won’t allow people to cross diagonally.

Next week, city crews will begin to dismantle the signals and striping for diagonal crossings.

“If they want to bolt across the street, they probably still can, I suppose,” Mitchell said. “But it won’t be legal.”

It’s an end of an era for Denver, where the “Barnes Dance” or “pedestrian scramble” was invented 60 years ago by the city’s first traffic engineer, Henry Barnes, who came to Denver from Flint, Mich., in 1947 to unclog the city’s tangled traffic problems.

Barnes came up with the idea of stopping all traffic at intersections and allowing pedestrians to cross in any direction.

Denver became a model of urban traffic management as the system was adopted worldwide, and Barnes went on to tackle gridlock in Baltimore and New York. He died in 1968.

One of the top reasons for the changes in the system is because RTD will be moving to four-car light-rail trains from the current three to accommodate increased ridership. That means the trains will need slightly longer blocks of time to get through the intersections.

On short blocks, a train with four cars would not fit without blocking traffic on other streets.

“That happens one time, and that would gridlock all of downtown,” said Matt Wager, assistant director of Denver’s traffic-engineering services, describing the problem of a train pulling into the light-rail platform at 16th and Stout streets.

Scott Reed, RTD spokesman, said the three-car trains were getting too crowded during peak times and special events such as Denver Broncos games.

“With a four-car train, you can carry so many more people,” Reed said.

Chris Streiff, who works for a nonprofit group downtown and who rides the D-line throughout the week, said he sees a need for more rail cars.

“During the rush-hour times in the mornings and afternoon, the light rail is packed,” he said. “I’ve stood the whole way from downtown to my stop in Littleton. It’s crazy. More cars are needed in rush hour.”

Also, the changes are required because the city must begin allowing pedestrians more time to cross the street to conform to new federal standards.

Apparently, walkers in the United States have slowed down, and federal standards have been adjusted to reflect our more slothlike ways.

The Federal Highway Administration’s Manual on Uniform Traffic Control Devices in 2009 said crosswalk signals should be calibrated for 3.5 feet per second instead of a jauntier 4 feet per second.

“It’s probably due to the baby boomers,” said Mitchell. “We’re the cause of everything.”

Jeremy P. Meyer: 303-954-1367 or jpmeyer@denverpost.com

Reporter Kurtis Lee contributed to this report.