Mayor Rahm Emanuel reached an tentative agreement with a Chicago Transit Authority workers union on Tuesday that the city says will speed up construction work — with taxpayer savings to boot. 

The agreement with the International Association of Bridge, Structural, Ornamental and Reinforcing Iron Workers Local Union #1 would cover almost 70 ironworkers, with changes that allow for flexible work shifts.

“This is a sound agreement that protects taxpayer investments and increases efficiency in services provided to the public,” said Emanuel.

The city says the new agreement will allow accelerated rehabilitation throughout the CTA’s elevated track structures, including a major slow zone remediation project on the Brown and Purple Lines between the Merchandise Mart and Armitage Avenue, known as the “Ravenswood Connector,” according to the mayor’s office.

Emanuel said the Ravenswood Connector rehabilitation will begin next spring and run through 2014. The Connector, which was built in the late 1800s, will undergo a $66 million structure and track rehab starting in 2013, the mayor’s office announced.

Local #1 Iron Workers will handle much of the structural ironwork repairs, representing more than half the project — including repair and replacement of components on the steel structure, according to a release.

The city said the Ravenswood Connector project with create about 180 new construction jobs, including 60 for ironworkers, 35 of which will be new hires. The CTA anticipates keeping the majority of the new iron worker positions after the project is completed in 2014 to accelerate preventive maintenance on rail structures.

“Iron workers are critical to the CTA’s operations, and our in-house forces work on nearly all of our capital projects, especially those involving structural work,” said CTA president Forrest Claypool. 

“Local #1 has been a very cooperative partner in reaching a tentative agreement that help us complete projects on time and on budget, while providing the best service possible to CTA customers,” he said.

The iron workers union was not immediately available for comment.