Traffic roundabouts once drew skepticism. Now Caltrans is among their biggest fans

In the tiny town of Plymouth, gateway to Amador County’s growing wine tourism area, road crews recently ripped out the four-way stop on a busy section of Highway 49 to replace it with a traffic approach that literally will have drivers going in circles.

Plopped in the middle of the intersection where Main Street crosses the highway, the big oval forces drivers to slow to 15 mph but doesn’t require them to stop. Instead, traffic from four directions merges and flows in a choreographed, counterclockwise direction.

Roundabouts have suddenly become one of the state’s trendiest traffic calming devices. After shying away from them for years, the state Department of Transportation is on a roundabout building spree, constructing 37, most in the last few years, with 100 more on the drawing boards.

The Federal Highway Administration has given its blessing, saying studies show roundabouts are substantially safer than “conventional stop-controlled intersections.” But it is also because communities like Plymouth have overcome initial opposition to the unusual “European-style” traffic calming devices and have pushed Caltrans to join in giving them a try.

The city of Sacramento installed smaller versions of roundabouts, called traffic circles, in midtown 20 years ago, and officials say they have worked well. New suburban developments now often employ roundabouts instead of stop lights to keep traffic calm but also to keep it moving.

Advocates say the devices reduce traffic jams and pollution by allowing vehicles on two different streets to flow continuously through a major crossroads. No one has to stop and wait. Caltrans engineers say the circles notably reduce the number of “points of conflict” in intersections where cars most often crash. In particular, vehicles do not have to cut directly in front of oncoming traffic to make a left turn, a maneuver that leads to broadside hits, one of the deadliest intersection crashes.

John Liu, a Caltrans traffic operations official and the agency’s leading advocate for roundabouts, says his agency was slow to embrace the devices, but has become a believer, when built in the right places.

“We were just very cautious,” Liu said. “Now, it’s proving to be one of the best tools in our toolbox.”

The state typically employs the circles where narrow rural highways run through little towns and criss-cross local streets, or where two highways intersect. Caltrans also has been building roundabouts at the base of freeway ramps, where they replace stop signs or traffic lights that can cause stalled traffic to back up dangerously onto freeway lanes.

In Plymouth, where wine tourism has increased traffic on local roads, new businesses are arriving and a housing subdivision is under construction on a nearby hillside, promising more cars in the future. Plymouth City Manager Jeff Gardner said be believes the roundabout will help keep vehicles flowing and cut down on crashes.

“We don’t even have the striping done yet and it is just working like a dream,” he said last week, watching as cars flowed down Shenandoah Road from the winery loop, merging with vehicles on Highway 49.

In some places, however, residents are still unnerved by them and contend that they cause, rather than solve, traffic woes.

On the north shore of Lake Tahoe, Kings Beach residents complain that two new roundabouts have added to congestion by slowing traffic through town. State and local officials say they meant to do that. When they added the roundabouts, they narrowed the highway from two lanes to one in each direction west of town to reduce vehicle speeds to make the area more pedestrian friendly.

A few miles away, in Tahoe City, state and county officials have the opposite goal in mind as they plan to build several larger roundabouts and realign and widen Highway 89. Those roundabouts should help speed traffic and unclog an area where summer weekend traffic often resembles a big city traffic jam.

Roundabouts, though simple looking, can be elaborate and costly. The budget for the one in Plymouth has crept to about $6 million, Gardner said, partly because it involves some street widening and a lot of curb and gutter work on the approaches to the intersection.

He said putting in traffic signals instead could have cost more, $9 million by his estimation, because it would have required even more widening to make room for numerous turn lanes. That would have required purchases of land and a possible tear-down of some adjacent businesses.

In Plymouth, the evolving public debate over the roundabout suggests that Californians are accepting them. When the idea for a roundabout at Plymouth’s main intersection first came up more than a decade ago, a local restaurant polled its customers and found they hated the idea. Some residents complained that the concrete intersection with curbs, gutters and sidewalks erases some of the area’s rural charm, which includes dirt shoulders.

Others initially find them confusing. Last week, as town manager Gardner stood on the sidewalk, a pickup driver slowed briefly to shout a sarcastic comment: “How many laps do I have to take before I get out?” And Sandra Sanders, who runs the nearby Plymouth House Inn, saw a driver go through the wrong side of the roundabout the other day.

Sanders initially opposed the roundabout. “I wanted to keep Plymouth the way it was. I liked the old Plymouth with the rural look, no sidewalks. Why are we having to look like Napa?”

Now, she says she loves it. “It’s cleaned up this corner. It’s going to help commerce.” It’s easier and safer, she said, for her guests to walk to Marlene and Glen’s Diner and the Amador Brewing Co. tasting room on the other side of the highway.

Tracey Emery Berkner, who operates Taste restaurant and Rest Hotel with her husband, also approves. She knows several people who have been in crashes at the intersection, and she has almost been hit by cars that seem to show up around the turn at the last minute.

She’s driven through roundabouts while traveling in France and thinks they work well. “I think it makes us look grown up,” she said.

The roundabout will be finished in the next two months. Its first real test will come later this year when tourism picks up, and when The Big Crush Harvest Festival and the Behind The Cellar Door events occur.

City Manager Gardner and Caltrans official Liu both say they think the roundabout will keep traffic flowing well for years without further expense.

“We are not going to have to come back in 10 years and tear up and expand the intersection,” Liu said. “We don’t have to re-time signals every year. We have less operational costs.”

The roundabout could soon prompt a new debate in town. The slightly elevated center of the island appears to be a prime spot to place something that makes a civic statement about Plymouth and Amador.

Gardner got the Plymouth City Council’s OK to temporarily install some old mining ore carts. But he said he wants public input on what should be there permanently, possibly decorative plantings, other Gold Rush memorabilia, an art piece or something reflecting the area’s wine region.

“Amador is up and coming,” Gardner said. “We’re still a rural community, but we are having to embrace new things. We’re moving forward.”

Tony Bizjak: 916-321-1059, @TonyBizjak