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Updating highway signs, even simple ones, is more complex than it seems

  • The former State House sign near Exit 14 on Interstate 93 in Concord. Courtesy of the N.H. Department of Transportation

Monitor staff
Published: 9/16/2019 1:37:15 PM

For those who are close observers of signage on Interstate 93, rest assured that downtown Concord is still historic and the Museum of New Hampshire History still exists.

They’re just not on the State House signs at Exit 14 anymore.

Welcome to the more-complicated-than-you-might-think world of highway signage, where the overriding authority of the Federal Manual on Uniform Traffic Devices runs into the messy complexity of real life.

“The whole purpose is the word ‘uniform.’ We try to be sure we are consistent across the state when we make changes,” said said Bill Lambert, state traffic engineer with the Department of Transportation. “But there’s a lot of gray area.”

Consider the State House signs in question, which anybody living or working in Concord has seen so many times that we’ve practically stopped noticing them. The two signs, one each on the southbound and northbound side of Exit 14, have white letters are on a brown background, which is a color (signified by hex code #660000) that indicates “points of recreational or cultural interest.”

That’s compared to the more common signs whose background is green (hex code #009900) and are officially called guide signs, or the blue (hex code #0000FF) background of “services information signs” letting you know what commercial services are available near the next exit. If you’re wondering, the government has also established specific uses for signs with backgrounds that are red, purple and even fluorescent pink. Officials haven’t yet decided what to do with “coral” (#CC0033) backgrounds, however.

The old signs said “Historic Downtown / State House / Museum of N.H. History / Exit 14” but the new ones just say “State House / Exit 14.”

The wording was altered when the signs were replaced because they were at least 15 years old and needed an upgrade, Lambert said.

“Sign sheeting doesn’t last forever. We replace it as part of routine maintenance, make sure signs are reflective, meet current standards,” said Lambert.

Although the signs are relatively small by highway standards they’re a lot bigger than it may seem when you’re zipping past – 12 feet wide and 5 feet tall for the new sign, several feet more in both dimensions for the older, wordier sign.

When replacement time came, the state Traffic Bureau had to decide what the new sign would, and wouldn’t, say. Changes about the best way to alert people to what’s ahead moved off mentions of the downtown and the museum, Lambert said, shifting them to blue services information signs.

“Both of those things are the types of tourist designation now eligible for specific service or logo sign program – blue signs – so we took them off,” said Lambert. “Of course, the State House is a tourist destination, too, but it also fits the category of cultural/recreational locations” suitable for brown signs.

“Shaker Village would have been on a brown sign in the past. The Audubon Society in Concord was a brown, now we have an attractions program where it belongs,” he said.

As you can guess, making such a decision isn’t always straightforward.

“Oftentimes, when we’re having discussions about taking certain things off the side of the highway, we’ll reach out to stakeholders to let them know that it’s on the table,” said Lambert. Chambers of commerce and tourism officials often have opinions about what they want to highlight.

It is complicated to the point that alerting drivers to a hamburger joint can require legislative action. This isn’t a joke: The blue signs telling people which services are available at an upcoming exit on I-93 can only mention attractions when you’re north of Concord, but the Legislature has tweaked the law to allow mention of upcoming food, gas, lodging or camping facilities when you’re south of Concord, presumably because the less pristine surroundings won’t be tainted by this extra commercialism.

Virtually all of the major interchange and highway signs in New Hampshire are made of foot-wide aluminum planks, cut to length and bolted together, then coated with a reflective sheeting and a separate reflective border and words. The work is done either by private contracts or the DOT sign shop on Route 106, said Lambert.

Those aluminum panels, by the way, are no-nonsense.

“When we tear down signs, some of the patrol sheds will use the panels as shelves, or ramps to bring mowers onto trailers, things like that,” said Lambert.

The coatings are also interesting. They have tiny prisms embedded in them to reflect headlights.

“The older material had glass beads but now it’s prismatic, which means light returns to the source at a wider angle so you see the brightness from a wider angle and side to side,” said Lambert.

Despite the importance that highway signs have in our car-centric lives, Lambert said the bureau doesn’t get a lot of complaints or suggestions from the public – perhaps, he says, because everybody uses their phones to figure out how to get around these days. That’s in contrast to another type of road sign, he said.

“Speed limits! There are a lot of self-proclaimed experts on speed limits out there,” he said.

(David Brooks can be reached at 369-3313 or or on Twitter @GraniteGeek.)

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