The company said that the crossing meets federal regulations but that it plans to "improve buffer time," which it described as time beyond what is required for the signal system.
"The buffer time is added to further ensure that the signal system always provides the warning time required by the federal government - as it did on the day of the accident that occurred on Nov. 15," Union Pacific spokeswoman Raquel Espinoza said in a statement.
The collision between the train and the parade float occurred at the start of a weekend of festivities to honor veterans wounded in the Iraq and Afghanistan wars. At least 14 people were injured in the crash.
Investigators with the National Transportation Safety Board said the warning bells began sounding and lights flashed at the intersection 20 seconds before the train arrived.
Union Pacific did not say how long before the arrival of a train the new signals would activate.
Two lawyers representing some of the injured veterans and their wives said Thursday that their experts found the problem with the crossing and that Union Pacific agreed to fix it. The group is suing Union Pacific as well as the company that provided the flatbed trailer used as a float.
"Every one of our clients made it very clear that their No. 1 priority in this case is to make sure nothing like this ever happens again," said one of the lawyers, Bob Pottroff. "There are another 100,000 (crossings) or so out there that we need to make sure don't have similar problems."
Union Pacific, citing a National Transportation Safety Board investigation, says that the crash was caused by the truck failing to stop at a red light.
"We would not be having this conversation had the truck not driven through the active railroad crossing signals," Espinoza said.
Smith Industries, the oilfield equipment company that provided the flatbed trailer, has declined to comment. (Reuters)