Exit signs on nearly a dozen major highways in Connecticut are being renumbered as the state Department of Transportation continues replacement of old signs to meet Federal Highway Administration standards.

By the end of the decade, Connecticut's busiest roads will have exit numbers that correspond with CT DOT's mile marker system, basing exit numbers on how far they are from the beginning of the route within the state's border. The system is the same exit numbering system used on most highways in the country.

For example, if your exit is at mile marker 23 of the highway, it will be Exit 23. If the exit is in between mile markers, the number is rounded down to the nearest whole mile. If a new exit is added, the mile is simply marked or a letter is added if it's close to an old exit.

Under the previous, sequential system, adding new exit numbers meant renumbering the entire highway unless the new exit happened to be at the end of the roadway.

The CT DOT said this was not a new project. The federal rule revisions were published in 2009 with no hard deadline for states.

"We timed it with other work that we know is going to be taking place," said Joshua Morgan, spokesperson for CT DOT. He explained that the exit number changes were attached to major highway maintenance projects to save time, money and logistical headaches. "That way when we know a sign is at the end of its useful life, we can tie it to an additional project that's already taking place."

The old highway exits will be noted with "Old Exit" signs under the new numbers for at least two years to help ease people through the transition. Several exits on CT-6 will get exit numbers for the first time in the road's history. The new signs will also be larger, the same color scheme and more wind-resistant than previous signs.

"People call Connecticut the 'land of steady habits' because we turn on a very slow pace when it comes to change," said Morgan. "But I think people will get used to it."

CT DOT has been telling technology companies that provide GPS navigation, like Apple and Google, the dates they expect the exit numbers to change.

"I actually commute on I-691 up to the Newington headquarters every day," said Morgan. "I saw the numbers change on a Monday or Tuesday. But it was only like a day or two later that my Google Maps was showing the new numbers."

Morton stressed that the change was because of longstanding federal requirements.

"We really appreciate the public hanging in with us on this," said Morgan. "Definitely call or email if you have questions or concerns."