The funding is uncertain and some of the technology is untested, but it appears a federal deadline to install an automatic braking system is definite, Metra officials said at a Friday meting.
That means the commuter rail agency will keep working to meet a Dec. 31, 2015, mandate to equip its lines with Positive Train Control, despite multiple obstacles.
"It's the largest unfunded mandate we've ever seen," Metra board Director Jack Schaffer of Cary said.
So far, Metra has set aside about $43.5 million in capital dollars for the program, which is estimated to cost $234.7 million.
The pricey technology, which can stop a train when a collision is imminent, has been in the news this month following a fatal crash in the Bronx that killed four passengers in a commuter train Dec. 1. The engineer apparently did not realize he was speeding on a curve, according to officials.
The crash also put PTC on the front burner for lawmakers. "Positive train control would have prevented two derailments on Metra trains in 2003 and 2005," Sen. Dick Durbin wrote in a letter to Metra last week, referring to two collisions on the Rock Island Line.
But there are also counter arguments that PTC isn't worth the extensive investment.
"Metra is committed to implementing PTC, but we also are committed to maintaining our bridges, tracks and other infrastructure critical to the safe operation of the railroad," Metra Chairman Jack Partelow replied to Durbin.
Metra will also face additional operating costs when it hires new signal operators and other employees to maintain the system.
Meanwhile, the software to run PTC is still being developed and an entire infrastructure of communications hardware will need to be installed in train locomotives and along tracks.
"I don't see how we will get it done by 2015," Acting Executive Director Don Orseno said.
"What happens when all the (commuter rail) agencies can't comply?" asked board Director John Zediker of Naperville.
Officials said the Federal Railroad Administration has indicated it will look at such situations on a case-by-case basis to see if a good-faith effort was made to comply.