In the blink of an eye, one of the tallest spaghetti-style ramp bridges of the I-59/20 interchange with the Red Mountain Expressway was dropped 50 feet to the ground Sunday morning.

Just before 8 a.m. Sunday, contractors working for the Alabama Department of Transportation detonated controlled explosive charges around the columns supporting the old ramp that led drivers from the RME (U.S. 31/280 Northbound) onto I-59/20 headed south and west, toward Tuscaloosa.

The charges obliterated the support columns, and the bridge immediately dropped straight down to the ground below, splitting in a few places and buckling in others. ALDOT said the ramp section that came down was 880 feet long in total.

Traffic was stopped on I-59/20 beginning at around 7:45 a.m. for the demolition work, and some local city streets, including Carraway Boulevard, had been closed since Saturday night.

33 Implosion of Red Mountain Expressway ramp to I-59/20 in Birmingham

The demolition of the old ramp was part of the $475 million project to rebuild the I-59/20 interstate bridges through downtown Birmingham. A one-mile stretch of I-59/20 downtown closed on Jan. 21 for an estimated 14 months as the old bridges are demolished and rebuilt between the interchanges with Red Mountain Expressway and I-65. The demolition phase is expected to last about two months, although construction and installation of the new bridges will be going on concurrently.

Most of the demolition for the project is being done without explosives, but ALDOT East Central Region Engineer DeJarvis Leonard said the ramp that was brought down Sunday morning was taller than the main interstate bridges and so mechanical demolition would have created safety concerns.

“The concerns they had with trying to mechanically remove it were, the bridge was so high and they’d have to put equipment on top of the deck and they were afraid that could cause a safety issue,” Leonard said.

For the main interstate bridges, contractors use heavy machinery sitting on the bridges themselves to chip away the concrete before removing the metal frame and knocking down the support pillars.

Less than five minutes after the charges were detonated, crews were chiseling away at the felled ramps with heavy equipment, breaking up the concrete from the old bridges. Within 15 minutes of the implosion, at least eight different pieces of heavy machinery were working to dismantle the old bridges before the dust had cleared from the initial implosion.

Subcontractor Lindamood Demolition, along with Controlled Demolitions, Inc. planned the detonations to drop the bridges to a contained area near the intersection of Richard Arrington Jr. Boulevard and Carraway Boulevard, just blocks away from Top Golf and the Uptown entertainment district.

Carraway Boulevard will be closed beginning at 9 p.m. Saturday night and will reopen by 5 a.m. Monday.

Carraway Boulevard is expected to reopen by 5 a.m. Monday for commuter traffic.

Leonard said the overall project was mostly proceeding on schedule, with one exception. ALDOT had planned to open both on- and off-ramps to I-59/20 from 25th Street North on Monday.

However, Leonard said, only the off-ramp to 25th Street from I-59/20 South will be opening Monday. The on-ramp will likely open next week.

Once the 25th Street ramps are operational, it will add another option for detour traffic going around the closed section of I-59/20 on the east side of town.