MIAMI -

Construction crews started demolishing an out-of-service flyover ramp connecting I-595 to the southbound lanes of Florida's Turnpike on Saturday.

The demolition is part of the $1.2 billion reconstruction of the two major roadways. Drivers are already using the new ramp used to connect Westbound I-595 to the Southbound Turnpike.

Northbound is shut down until 1 p.m. Sunday to keep drivers safe. Until then, drivers are being rerouted.

VIEW: Florida's Turnpike closures

The detour will take drivers eastbound on I-595, where they can get off on 441 and head north to Sunrise Boulevard. There, drivers will be able to hop back onto the Turnpike. The southbound lanes are expected to be open with a single lane. 

A contractor, who specializes in bridge demolition, has been brought in to do the job. All told, it will take two dozen crew members some 10 hours to bring down the old ramp. The carefully choreographed demo will include more than a wrecking ball. 

"It’s a steel girder bridge, so they'll be demolishing the concrete deck and taking down the steel beams one-by-one,” said Paul Lampley, the project manager. "They'll be using specialized equipment for the demolition.”

Construction crews laid out a bed of sand on the Turnpike going in both directions. A cover on the northbound side should keep the debris from flying eastbound.  

Once the debris is hauled off, the sand will be swept and the lanes will re-open.

Be sure to check traffic and road conditions before heading out this weekend.