Driving Iowa's roadways
The National Cooperative Highway Research Program (NCHRP) Report 500 Series, A Guide for Reducing Collisions Involving Older Drivers, provides recommendations to improve the roadway environment for older road users including the following.
- Advance warning signs that inform drivers of existing or potentially hazardous conditions, such as: speed reduction areas, narrow roadways, potential conflict zones (intersections, bike or pedestrian crossings), construction and maintenance zones.
- Advance guide and street name signs that inform drivers about their location and route and give the driver additional time to make necessary lane changes.
- Increased size and letter height of roadway signs to help older drivers see the information.
- All red clearance intervals at signalized intersections to accommodate older drivers' slower perception and reaction time.
- Protected left-turn signal phases at high-volume intersections to decrease potential conflicts between left-turning and opposing through vehicles.
- Offset left-turn lanes at intersections so that vehicles in opposing lanes no longer obstruct the opposing driver's view of oncoming vehicles.
- Improved lighting at intersections, horizontal curves, and railroad grade crossings to compensate for deterioration in visual acuity.
- Improved roadway delineation to give the older driver better visual cues through pavement markings, raised channelization at intersections and delineators at horizontal curves.
By their nature intersections can be the most dangerous of roadway features. They are the one place where all roadway users come together in a mix that has the greatest potential for conflict.
As you age, left turns become more challenging because you start to lose your ability to judge the speed and distance of oncoming traffic. If you are uncomfortable making left turns, avoid making them. You can sometimes make three right turns to avoid having to make a left.
One way transportation departments have sought to improve safety at intersections is through installation of roundabouts. A modern roundabout is an unsignalized, circular intersection engineered to maximize safety and minimize traffic delay. Roundabouts are sometimes called the safest form of traffic control in the world, and they are also some of the most attractive features in modern roadway design. While roundabouts help eliminate a number of safety problems, they also can be confusing for drivers when they are not familiar with them.
Several roundabouts have been constructed throughout Iowa. The Iowa DOT has a Web site on roundabouts that includes information on the benefits of roundabouts, myths and facts, frequently asked questions, how to navigate a roundabout, etc. For more information, click here or visit the Iowa DOT's Web site at http://www.iowadot.gov/roundabouts.
The following are additional resources developed by agencies to educate drivers on the use of roundabouts.
- The Insurance Institute for Highway Safety (IIHS) has developed a Roundabout Question and Answer Web page and also a two-minute video on "How Roundabouts Work" that can be accessed by clicking here or visit the IIH's Web site at http://www.iihs.org.
- The Florida Department of Transportation has developed brochures on how to navigate through roundabouts. Information on one-lane roundabouts can be found by clicking here or visit the Florida DOT's Web site at http://www.dot.state.fl.us/trafficoperations/Operations.
The Michigan Department of Transportation has information on their Web site about roundabouts, including common misconceptions about this roadway feature plus other articles: http://www.nwconnector.com/education.cfm.
Countdown pedestrian signals
Countdown pedestrian signals improve pedestrian safety by reducing the number of pedestrians stranded in the crosswalk when the light changes. They consist of a regular pedestrian signal with standard shapes and color, and an added display showing the number of seconds left to safely cross the street.
The countdown time period is based on walking speed and crossing distance. For instance, an eight-lane highway would have a longer countdown period than a four-lane road. Once the countdown period starts, a pedestrian should not start crossing the roadway.