The Anoka County hamlet of St. Francis has embraced the cutting edge of traffic design — the roundabout — but not without some hand-wringing.

Planned since 2011, two roundabouts recently opened along Bridge Street NW. in front of St. Francis High School, replacing dual intersections. The idea was to combat growing congestion, particularly as 1,500 students take to bus and street every school day, and as big trucks rumble across the Rum River onto the busy thoroughfare.

It was a project that prompted concern for some of the city's 7,300 residents.

But it's also a decision mimicked by countless communities throughout Minnesota and across the country, as roundabouts steadily grow in popularity. Engineers say they are safer for both motorists and pedestrians than traditional intersections with traffic signals. The idea is to keep traffic moving — albeit at a slower, more reasonable, pace.

Detractors say the $3.8 million project in St. Francis — fueled by a $1.35 million federal grant — is overkill. Some residents question how police, fire and emergency vehicles will snake through two lanes of Bridge Street traffic between the roundabouts in an emergency.

Anoka County only has two other roundabouts. The northern suburb "was a little slow to the game with roundabouts," concedes County Engineer Doug Fischer. "Before we got into the roundabout business, we wanted others to perfect them first."

The decision to build them in St. Francis came after two previous federal grant applications to rebuild the existing Bridge Street intersections were rejected.

"We looked at some of the other projects that got funding, and we saw that roundabout projects were scoring better," Fischer said. "We didn't do the roundabouts because it's the flavor of the month, we did it because it solves our problems."

The Minnesota Department of Transportation built its first roundabout in 1995; now there are 60 of them on state highways. It's unclear how many roundabouts are located in Minnesota, because the state, counties and cities keep their own tallies. In the city of Blaine, for example, there's a roundabout near a Wal-Mart.

In most cases, engineers opt to install a roundabout for safety reasons. John Hourdos, director of the University of Minnesota's Traffic Observatory, notes that speeds in roundabouts are generally no more than 25 miles per hour, and there's a reduction in conflict points "where one car can meet another."

But motorists are often unsure how to drive through roundabouts. St. Francis is working to educate residents on roundabout etiquette. Its website links to a YouTube video with tips on driving through a roundabout, right next to information about water softeners.

As Cmdr. Brian Podany, of the Anoka County Sheriff's Office, put it: "Look left, go right."

One challenge is that roundabouts are often confused with traffic circles (or rotaries) — their bigger and more muscular cousin. Popular on the East Coast and in Europe, traffic circles are famously known for inspiring aggressive motoring (to put it politely).

Roadway design engineer Andrew Plowman of Golden Valley-based WSB & Associates says that, at 120 feet to 180 feet, roundabouts are smaller than traffic circles (which typically are twice that size) and are therefore easier for drivers to maneuver.

When working with municipalities contemplating roundabouts, Plowman says he likes to do a little "mythbusting" — debunking the notion that roundabouts are crazy traffic free-for-alls.

"We label the myth we anticipate people might be concerned about and state the facts," Plowman said.

At an open house for the public in St. Francis three years ago, Plowman showed a clip from the movie "National Lampoon's European Vacation." It features Chevy Chase (as Clark Griswold) driving endlessly around a London roundabout, laughing maniacally while declaring: "Can't seem to get left! Look, kids! Big Ben! The Houses of Parliament!"

Plowman's work on the roundabout at 66th Street and Portland Avenue S. in Richfield was recently featured in the magazine RoundaboutsNow.

So far, the only real issue to surface regarding the St. Francis highway project has little to do with the roundabouts.

Some residents say the stretch of Bridge Street NW. between the roundabouts, now two lanes in front of the high school, is too narrow to accommodate police and emergency vehicles in traffic.

"It's a huge issue — it's too narrow," said Marsha Van Denburgh, chairwoman of the St. Francis school board, and a candidate for Anoka County commissioner. She said people in the community are worried about overall pedestrian safety in the area, as well.

At 18 feet wide, the lanes meet federal and state highway standards. Still, former mayor (and current mayoral candidate) Jerry Tveit has called for city officials to come up with a plan for emergencies along the narrow patch of road.

St. Francis acting Police Chief Todd Schwieger said police will not activate their sirens or emergency lights on that one-block stretch between the roundabouts if vehicles are present. That way, motorists won't freak out and freeze in the middle of the street while police try to edge around them, eating up precious seconds in an emergency.

"We don't want people panicking," Schwieger said.

It's unclear, however, whether the city's fire department will embrace a similar protocol. Officials did not respond to requests for comment.

Janet Moore • 612-673-7752 @MooreStrib