Round and round and round it goes.

Will motorists embrace the Astoria roundabout? ODOT thinks so.

Local drivers and the Oregon Department of Transportation are entering new territory together with the construction of the circular traffic control device at Smith Point, which starts Monday.

The roundabout, scheduled for completion this fall, will be the first of its kind on an Oregon highway, and the first two-lane roundabout built by ODOT. But state and local officials think it's the best method for easing the chronic congestion at the intersection of U.S. Highway 101 and Oregon Highway 202 at the Astoria end of the Youngs Bay Bridge.

With their combination of slower speeds and continuous movement, roundabouts are considered to be safer alternatives to the standard intersection with traffic signals, according to ODOT Community Relations Coordinator Ed Schoaps.

In a roundabout, traffic revolves in one direction around a central island, with vehicles continually entering and exiting.

"It eliminates a lot of stop-and-go, and eliminates left turns, the most dangerous type of traffic movement at any intersection," he said.

The first portion of the $1.2 million Astoria project will involve installing a temporary stoplight that will control traffic while the roundabout is being built. Crews will work at night to minimize disruptions on that phase, which is expected to take two weeks.

With the light in place, there should be no major traffic restrictions for the length of the project, because the roundabout itself is located away from the lighted intersection, according to ODOT Project Manager Dave True. There will be some delays and closures at the intersection of Florence Avenue, but access to and from Hamburg and Portway avenues should remain unrestricted, he said.

Along with the light, Taylor Avenue, which runs just east of the intersection between Florence and Hamburg avenues and currently provides access to an RV dump station, will be opened up to traffic traveling from Highway 202 to Marine Drive.

The entire project is scheduled for completion by the end of October.

ODOT needed some convincing before it decided a roundabout was the best option for Astoria.

Agency engineers gave a preliminary thumbs-up to the project in late 1998, followed a few months later by the state transportation commission. In June 2000, however, ODOT reversed itself, announcing it was abandoning the roundabout plan and instead pursuing a traditional stoplight intersection at Smith Point.

Agency officials said further review of the plans indicated that the circular system wouldn't work - a one-lane roundabout couldn't handle the traffic volumes coming north on Highway 101, and a two-lane structure would create a hazardous turning situation for traffic turning south off Highway 202.

The Astoria City Council, unhappy with that decision, commissioned its own study by Kittelson and Associates consulting firm, an expert in roundabouts, which reviewed ODOT's design and engineering data and came to the conclusion that a roundabout would work. Based on those findings and some design changes, ODOT changed its mind and endorsed the project.

The primary difference between a standard stoplight and a roundabout - and the roundabout's biggest advantage from ODOT's point of view - is the fact that traffic continues to move at the intersection, albeit at a slower pace, Schoaps said. The design speed of the Astoria roundabout is between 17 and 21 mph - the posted speed will be 15 mph.

And because traffic is moving slowly and in the same direction, if accidents do occur - and ODOT officials admit they do, especially when the roundabouts are first installed - they tend to be minor fender-benders rather than the more serious collisions that can occur at traditional intersections where vehicles are moving faster and turning in front of oncoming traffic.

Left turns, specifically by people turning south onto the bridge from Highway 202, present the biggest hazards at the intersection today, according to Mayor Willis Van Dusen, who welcomes the new project.

"It's very dangerous - people wait so long, and they get impatient," he said. "We've had some accidents there, and close accidents."

The city had hoped to set up a "trial roundabout" at the expansive parking area of North Tongue Point to test out the design, but that proposal proved to be too expensive, and it would not have re-created all the features of the real thing, which will include banked turns, Van Dusen said.

Nonetheless, the mayor is confident that with a bit of practice, motorists will get the hang of the new system without much trouble.

How they work

Motorists approaching the roundabout choose the proper lane for the direction they're heading. They slow down, looking to their left for vehicles already in the circle. If there's an opening, they pull in, following the circle in a counter-clockwise direction until they come to the exit for their route, following it off to the right.

Tractor-trailer rigs and loaded log trucks will have to use both lanes within the circle to negotiate the tight turns. But other large vehicle combinations, such as RVs towing passenger cars, can travel through the circle within one lane, Schoaps said.

The design probably will be unfamiliar to most motorists when it first opens, but "there is not that big of a learning curve," he said. The key is slowing down and yielding to cars already in the circle.

"The first few times, drivers will probably use extreme caution, but as they get used to it, it will become second nature," he said.

True said some Bend residents took two or three trips around that city's new roundabout before they were able to find their way to their desired exit, but overall "it seemed to work well."

The Astoria design includes small islands at the three entrances that will help guide vehicles in the right direction, and the interior of the circle includes a 15-foot apron that will provide extra room for large trucks or cars needing to get out of the lane.

The Bend roundabout is the only one recently built in Oregon, but the systems are catching on in the rest of the country, where about 300 have been built in the last 10 years.

A recent national study found that accident rates at roundabouts are far lower than at traditional intersections, with injury crashes only one-fourth as frequent.

Based on projections, the Astoria roundabout should still be able to handle traffic at the Smith Point intersection 25 years from now, Schoaps said.