STOP and read our guide to traffic control methods new to Iowa

CEDAR RAPIDS — Too many cringe-worthy near misses involving kids and vehicles have occurred at a crosswalk near Pierce Elementary over the past five years, says Tammy Long, a crossing guard at the school.

Cars bottlenecked, vehicles struggled with turn radiuses and traffic controls hid in blind spots near the crossing at the intersection of 42nd Street and Marilyn Drive NE. Long voiced concerns to anyone who'd listen. This fall she felt a sense of accomplishment when 42nd Street NE reopened after construction with a new system in place.

The crossing had moved 60 feet west and had a new traffic control device called a pedestrian hybrid beacon, which is similar to an overhead traffic light but has three lights that form a triangle and remain dark unless activated by a pedestrian.

'It's a new system and drivers aren't used to it yet, but I like the idea,' Long said. She thinks in the long run kids are going to be safer and traffic flow is likely to improve.

New traffic controls are popping up all around Cedar Rapids and throughout Eastern Iowa. In some cases, changes may be so subtle or intuitive, drivers hardly notice, such as flashing yellow left turn arrows. Other examples, such as roundabouts, road diets or pedestrian beacons, come with a learning curve.

Research, data and new technology have created new techniques for traffic control, which transportation planners say reduce collisions, improve congestion and may boost fuel economy.

'Data will reveal a certain issue and then a researcher will look for solutions. Then, they are rigorously vetted,' said Darian Nagle-Gamm, a senior transportation engineering planner for Iowa City. 'It takes a while for new tools and practices to become available for use.'

Here is a closer look at seven new traffic control measures you may have encountered:

— Pedestrian Hybrid Beacon —

When activated, motorists first see a flashing yellow light, then a solid yellow, and then solid double red lights giving full right of way to the pedestrian.

After about 10 seconds, the red lights alternate flashes or 'wig wag' similar to a railroad crossing, telling the driver to stop and then proceed if the crosswalk is clear. Several seconds later the lights dim. The default setting is dark, which means the driver has the right of way.

'This will grab motorists' attention,' said John Witt, assistant traffic engineering manager for Cedar Rapids.

This control reduces traffic delays compared to a traditional signal by up 50 percent, and reduces crashes involving pedestrians by 69 percent and total crashes by 29 percent, he said.

These are installed in four Cedar Rapids locations, including on 42nd Street NE just west of Marilyn Drive NE, 76th Avenue SW just west of Prairie Hawk Drive SW near the Prairie Schools campus, C Avenue NE at Huntington Ridge Park, and 12th Avenue SE just east of 10th Street SE.

— Flashing Yellow Left Turn Arrow —

These control a 'permissive' left turn, such that a turning driver yields to oncoming traffic but can proceed if no cars are approaching. It replaces the solid green light in a left-hand turn lane, which some motorists misinterpret thinking they have the right of way, Witt said.

'It is more easily understood,' Witt said. 'This grabs your attention and reminds them to yield to oncoming traffic.'

These signals have been installed at 15 intersections around Cedar Rapids, including at the north and southbound 42nd Street NE entryways to Interstate 380 and along Sixth Street SW at Third Avenue SW and Eighth Avenue SW.

— Road Diet —

A four-lane road shrinks to two lanes with a center turn lane and bike lanes on the outside of the motor vehicle lanes.

Iowa City recently installed road diets on First Avenue as part of a railroad underpass project and on Lower Muscatine Road. Next spring, the road diet on First is slated to be extended from Highway 6 to Bradford Drive near South East Junior High, and on Mormon Trek Boulevard from Highway 1 to Melrose Avenue.

'Lane reductions and road diets came about, as with most of the new technologies, as a safety measure,' Nagle-Gamm said. 'In recent years, we realized four lane roads have inherent safety issues.'

Left turning vehicles on a four-lane road cause congestion and create blind spots for other motorists, she said. Research shows road diets reduce crashes by eliminating conflict points, and carry the same amount of traffic despite fewer lanes, Nagle-Gamm said.

— Roundabout —

Roundabouts are becoming increasingly prevalent in Corridor cities and more are on the way.

Cedar Rapids planners have proposed a roundabout at Kirkwood Boulevard SW right outside Prairie Point Middle School. North Liberty recently installed its first roundabout at Dubuque Street and North Liberty Road NE near the new Liberty High School. Vehicles enter roundabouts from multiple directions. There's no stop signs but entering traffic yields to traffic coming from the left.

'With high school drivers there's a concern of them blowing through stop signs or red lights,' said Nick Bergus, a spokesman for North Liberty. 'The types of collisions you get there, a car t-boning, are very severe. Collisions with a roundabout are a much safer variety for an inexperienced driving force.'

Nagle-Gamm, citing research, said roundabouts reduce fatal collisions by nearly 90 percent, injury collisions by 75 percent and collisions overall by 37 percent, improve fuel economy and reduce traffic backups.

— Stop Signs Replacing Traffic Lights —

Last month in Cedar Rapids, an all-way stop replaced the traffic signal at 34th Street and Cottage Grove Avenue SE.

The same thing happened at the Center Point Road and J Avenue NE intersection.

City officials have been re-evaluating intersections when construction work occurs to see if traffic volumes still warrant a signal, Witt said. Safety and traffic efficiency are the dominant considerations, but stop signs are much cheaper to install and maintain than a signal, which has recurring costs, he said.

— Rectangular Rapid Flash Beacons —

These are diamond shaped street signs, such as on First Street SW in front of the Ingredion plant and A Avenue NE in front of St Luke's Hospital, that flash yellow warning lights when a pedestrian is present. They are designed to be placed mid-block when other traffic controls aren't present.

This approach has proved successful at grabbing motorists' attention and getting them to yield at crosswalks for pedestrians, Witt said. Plus, these solar-powered devices cost $10,000 to $15,000 and require little maintenance, while pedestrian hybrid beacons can cost $75,000 to $100,000 to install, he said.

— Larger Street Signs —

Cedar Rapids is replacing its street signs with larger signs intended to be more visible and easier to read.

The signs continue to have a green background with white lettering. Thus far, the signs have been installed in various locations in downtown, and a scattering of blocks elsewhere around the city.

'New, larger signs are phased in as old ones reach the end of their shelf life, or if they need to be replaced as part of a project,' Emily Muhlbach, a city spokeswoman, said.

l Comments: (319) 339-3177; brian.morelli@thegazette.com