DALLAS (CBSDFW.COM) – The most-ridden commuter rail line in Texas still does not have a life-saving braking device Congress ordered all trains to install nearly a decade ago.

The Trinity Railway Express (TRE), which takes on average 8,000 passengers between Fort Worth and Dallas daily, is in the process of installing the safety technology called positive train control.

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The TRE plans to have the technology installed by the end of 2018 but it will likely not be in use until 2020, according to train officials.

In the National Transportation Safety Board’s preliminary crash report on the deadly December Amtrak train derailment in DuPont, Washington, federal investigators noted the accident would have been prevented had the train had positive train control technology.

Amtrak derailment in Washington.

A positive train control system would have automatically slowed down the speeding Washington train. Investigators said the train derailed because it was going too fast on a curve in the track.

Since 2008, according to the NTSB, there have been 23 train crashes, resulting in 52 deaths, that could have been prevented if the trains had this technology.

The way the technology works is computers installed on the trains and along the tracks notify the engineer, using way satellites and radio signals, if the train is going too fast or if there is a problem with the track ahead. If the engineer does not slow down, the system automatically stops the train.

The CBS 11 I-Team has found for the past decade the TRE has been slow to implement this technology.

Weeks after the 2008 train collision in Chatsworth, California that killed 25 people, Congress passed a law requiring positive train control technology to be installed in all commuter trains by 2015.

The TRE, which is a partnership between Dallas Area Rapid Transit (DART) and the Fort Worth Transportation Authority, sent out a memo in December 2009 writing it is taking steps to implement positive train control systems with the plan to have it done by December 2015.

Then just months before that 2015 deadline, a speeding commuter train in Philadelphia jumped the tracks. Dozens were injured. Eight people were killed.

The federal accident report from the Philadelphia derailment noted the crash could have been prevent by a positive train control system.

Federal accident report from Philadelphia derailment.

However, after the fatal crash in Philadelphia, instead of making sure all commuter rails had the life-saving technology, Congress gave railroads three more years to install the technology. Lawmakers pushed back the deadline for positive train control technology to 2018.

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Nine years ago, the TRE said it would have positive train control up and running by 2015. The technology has yet to be installed.

“We are putting it in on the TRE right now,” said Reed Lanham, operations manager for the Fort Worth Transportation Authority.

Lanham said the safety technology is needed on the TRE but added it has been difficult finding the money to pay for it.

“While safety is the top priority and we always want it to be, it was an unfunded mandate so for smaller commuter line agencies it’s tough to come up with that funding,” Lanham said.

The technology will cost the TRE $45 million.

Lanham said there has also been technical challenges that have slowed down the process.

“We were hoping to have it sooner but, right now, no later than the final deadline which is December 31st, 2020.”

Trinity Railway Express

While the federal deadline for this technology is this year, Congress has given the TRE, along with others, an extra two-year extension for testing and implementing the system.

TRE officials say there has not been a single accident in its 22 years of operation that could have been prevented with this new safety system.

The TRE is one of several rail systems across the country that has not yet installed positive train control technology.

The Denton County Transportation Authority, which runs the 21-mile A-train commuter rail from Carrolton, up through Lewisville and Denton, has already installed all of the positive train control equipment and is in the process of training all of its employees on how to use the technology.

The new TEXRail, which will run from downtown Fort Worth up through northeast Tarrant County, will have the technology already installed in the trains when it begins operations later this year.

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DART is a light rail system. The law requiring positive train control only pertains to commuter railroads and freight train systems.