What if Chicago was hit by a giant tornado? Or massive flooding?

How best to evacuate the city in case of such an emergency now will be studied, thanks to a $2.9 million federal grant awarded to Argonne National Laboratory. Researchers at the lab near southwest suburban Lemont will partner with Pace and Metra.

The tools created will let public transit planners run disaster and emergency simulations so they can bolster transit weaknesses, evaluate new technology and develop techniques for getting people around — or out — fast in the wake of a disaster, whether natural or manmade, according to Argonne. They’ll also provide real-time assistance during a disaster by showing officials where trains and buses are and estimates of where people live and work, especially people with disabilities and the elderly who might need more help.

With a wide range of integrated transportation and mass transit systems, Chicago will act as test grounds for new emergency planning and response tools that once completed — expected sometime in 2017 — be shared with other cities.

“In an emergency situation, planning is everything,” said U.S. Sen. Dick Durbin, one of Illinois’ supporter of the grant from the U.S. Department of Transportation. “A lack of evacuation procedures or a failure of coordination among transit systems can have catastrophic consequences during emergency. Using the Chicago area’s multimodal transportation network as a research site, scientists at Argonne National Laboratory will use this federal funding to develop tools that can be used by transit agencies across the country for planning and reacting to emergencies.”

Home to the second-largest public transportation system in the country, Chicago “presents some interesting challenges to transportation planners, due to its proximity to Lake Michigan and its system of rivers,” said Argonne’s Hubert Ley, the project’s principal investigator.

Argonne will use POLARIS, its open-source high-speed computer designed for transportation planning, as well as its vast data sets about every street, waterway and traffic light in Chicago so researchers can study how traffic functions.

Ley said Metra has capacity to move lots of people at once, especially at times when traffic is heavy, though its 240 stations are in fixed areas. Pace, on the other hand, can adapt quickly to changing locations and conditions when moving people around, he said.

The Urban Transportation Center at the University of Illinois at Chicago and the Department of Civil, Architectural and Environmental Engineering at the Illinois Institute of Technology also will be involved.

The grant money is provided by the U.S. Department of Transportation’s Federal Transit Administration as part of a $29 million investment awarded last week to improve emergency response on public transportation in nine states.