Outline
- Introduction
- Discussion
- Description
- Types of roundabouts
- Using roundabouts
- Factors to Consider during Construction
- Advantages of Roundabouts
- Roundabouts vs. traffic lights
- Limitations of Roundabouts
- Conclusion
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Roundabouts instead of Traffic Lights
Introduction
Roundabouts and traffic lights are both used as controls on the road. Some people prefer roundabouts while others prefer traffic lights. Many people prefer roundabouts because they consider them safer and more efficient than traffic lights. When using traffic lights drivers have to stop and idle for some time as they wait for the lights to change, even if there are no cars from the other directions. This is time consuming, and it wastes fuel. Roundabouts do not need constant maintenance, and this saves the state authorities money. Traffic lights have to be managed to ensure that they are working correctly. They also consume a lot of energy during operations. They have to stay on whether there are cars on the roads or not. Once the drivers understand the rules of using roundabouts, they become more efficient, and this saves them money.
Discussion
Description
Roundabouts are the circular road intersections whereby the people drive in a counterclockwise direction around a center island. The center island is significant as it controls the traffic direction and ensures that drivers slow down. The design of the roundabouts and the inclusion of the island ensure that drivers do not collide. Modern roundabouts do not have any traffic signals or any form of stop signs. Instead of stopping on the roads, drivers yield at an entry point before entering the intersection. Once they are in the intersection, they exit at their preferred exit. All types of vehicles can use roundabouts regardless of their size (WSDOT).
Types of roundabouts
Most of the modern roundabouts are single lane. However, some roundabouts in the country have two lanes. Some people have successfully experimented with three-lane roundabout. Some neighborhoods use mini roundabouts to control traffic. They are especially effective in urban environments that encourage low speeds. The mini roundabouts are used in place of stop signs and traffic signals. The design of mini roundabouts is different from that of modern roundabouts on the roads. The center island is designed in such a way that larger vehicles can pass over it. The diameter is smaller because there is limited space. The splitter islands are not raised. The crossing distance is small and the vehicle speeds used are low. These features are aimed at improving safety (IIHS).
Using roundabouts
To avoid confusion when using roundabouts, signs and markings on pavements indicating directions and the action to take guide the drivers. This ensures that the drivers use the right path when entering. Drivers need to check the signs and arrows so that they can enter the proper lane in the roundabout. Roundabouts have truck aprons, which makes it possible for truck and trailer drivers to use them. Truck aprons are areas that are raised slightly in the center island that create additional room, which enables large vehicles to navigate (FHWA). Large vehicles use their rear wheels to pass through the truck aprons. The aprons are specifically meant for larger vehicles such as trucks and buses. They contain materials that have a different texture from that used on the main road on the roundabout, and this ensures that smaller vehicles do not use them (IIHS). Roundabouts are dissimilar from traffic circles or rotaries. The traffic circles have stop signs, and they are larger compared to the roundabouts. The rotaries can become congested since drivers do not have to yield once they enter an intersection (WSDOT).
Factors to Consider during Construction
Many people are opting to construct roundabouts as a way of enhancing efficiency on the roads. When deciding on a traffic control, the engineers have to consider the traffic history at the intersection. This includes examining and analyzing details concerning the accidents that have happened in the area. Such information would include the speed at which the cars were traveling, the type of crash that occurred, and the number of accidents that have happened in the area. In addition, the engineers have to consider how the intersection operates. They have to consider how traffic operates, as well as the backups experienced on each lane. Those making the decision concerning the type of traffic control to use have to consider the type of vehicles that will ply the route. Large trucks require more space than smaller vehicles and this will affect the way engineers design and construct the roundabouts (WSDOT).
Advantages of Roundabouts
Constructing roundabouts can seem more expensive in the short term compared to installing traffic lights. However, in the end, the investment is recovered and one realizes that roundabouts are cheaper. This is because the operating and maintenance costs are lower compared to the traffic lights. Constructors do not have to worry about installing any equipment. Any cost incurred after the construction of the roundabout would involve landscaping, which is inexpensive. In addition, roundabouts offer services for a longer period compared to other traffic controls (FHWA).
Many government authorities and other organizations support the use of roundabouts because they help to reduce motor vehicle accidents. Drivers have to slow down when using roundabouts. Speeds are often low, and this reduces the chance of major accidents. Whenever an accident happens at a roundabout, it is often minor and does not lead to injuries or fatalities since it occurs at low speeds (Williams). Roundabouts are designed for continuous driving and traffic continue to flow at intersections. Drivers save time since they do not have to stop when there is no traffic.
Roundabouts help in beautifying the environment, since they can be landscaped. The central and splitter islands can be landscaped using different trees, flowers, shrubs, and grasses. This adds more green to the environment, and it enhances livability in the community. In addition, they contribute to a greener environment. They do not have to use any fuel to operate efficiently. They reduce the time that drivers take on the roads. This means that the drivers consume less fuel, and this reduces the emissions such as carbon monoxide and hydrocarbons released to the atmosphere. Many vehicles in a traffic jam can cause some level of noise pollution. The additional screeching and immediate stops as drivers navigate sharp turns and hurry to avoid changing lights increases noise. Roundabouts eliminate this since the drivers do not have to worry. Moreover, the drivers do not stay in one lane for a long time since there are no traffic jams.
Roundabouts can be constructed in different types of roads. Engineers have constructed them in urban and suburban areas, interchanges, and high speed rural roadways. They can also be constructed on state roads. Roundabouts are suitable in many different intersections. They can be constructed in areas where the geography is complicated and in regions with many left turn movements. They are also suitable at freeways and areas with congested arterials (IIHS). However, it is essential to note that the type of road and the traffic expected can determine the design applied in the construction of roundabouts. Good design ensures greater effectiveness of roundabouts (FHWA). In some cases, the space is limited and the topography of the region discourages the construction of roundabouts. Traffic balance matters when constructing roundabouts. It is not recommended to build roundabouts in areas where traffic flows are highly unbalanced. In such areas, the main streets have high traffic volumes while the side streets have light traffic (IIHS). The designs applied are different, and engineers have to consider many different factors. Roundabouts require less space in the approaching roads than they do near intersections.
In addition to reducing accidents by driving at slow speeds, roundabouts also increase road safety by enhancing pedestrian safety. Roundabouts do away with the sharp turns that are present at other traffic controls. Pedestrians have a short distance to cross because of the splitter islands. They only have to cross one direction at a time, and this reduces any chance of encountering an accident. This added feature is also noteworthy for people who use bicycles to travel. They can use the splitter islands just like the pedestrians. They do not have to worry about cars coming from different directions and they can cross the road safely.
Roundabouts vs. Traffic lights
Traffic lights are not as safe as many people would like them to be. Some people are not patient, and they do not wait for the traffic lights to change (Roundabouts USA). This is a clear traffic violation, and it can cause injury and death. For instance, when a driver passes a red light, he or she could hit someone who is crossing the road. Children may not always understand the meaning of traffic lights. They can cross the road when they are not supposed to, and this can be dangerous. Some drivers speed off in an attempt to beat a traffic light. They do not want the traffic light to turn red when they have not passed their intersection. This has encouraged dangerous and speedy driving. Such incidences often lead to accidents. In addition, traffic lights often lead to driver irritation, especially if one is in a hurry (Williams)
Roundabouts are efficient in different ways. They save resources in the sense that they do not use any form of energy and they do not require maintenance. Power outages affect traffic lights. Whenever there is a power outage, the intersection at the traffic lights acts as a four-way stop, which slows down traffic. In some cases, police have to control and direct traffic. However, this is not necessary when using roundabouts. Traffic continues to flow irrespective of the power situation. Roundabouts are able to handle more traffic because of the continuous movement. When using traffic lights, cars have to line against each other as they wait for the lights to change. This creates traffic jams and drivers end up spending more time on the road and consuming more fuel.
Limitations of Roundabouts
Although roundabouts improve road safety, they are not immune from accidents. Some drivers are careless on the roads, and they can cause accidents regardless of the type of control used. Other drivers are not knowledgeable about roundabouts. They do not know how to drive on different intersections, and this is a leading cause of accidents. People driving at high speeds end up colliding at the central island. The main crashes that happen at roundabouts are sideswipes, run-off-road, entering-circulating, and rear-end. These are less risky than the head on collisions that are common at other traffic control intersections. The head on and right angle collisions, which are common in signal-controlled intersections, have more damages. In addition to causing property damage, they also lead to injuries and loss of lives. Collisions at roundabouts are more common entrances than exits. Collisions at roundabouts mostly cause damage to property. The low speeds are especially helpful in reducing damage (IIHS).
Conclusion
Roundabouts are a form of traffic control. They are used to direct and control the flow and direction of cars on the roads. They have become one of the most preferred traffic control choices because they increase safety. Unlike other traditional methods of traffic control, the drivers have to reduce their speeds at intersections. The low speeds ensure a reduction of accidents. Roundabouts are preferable to traffic lights. They encourage safety, can be used in different types of roads, and they are relatively cheap to maintain. In addition, they enhance and improve the environment since they can be beautified through landscaping. They also ensure less noise and air pollution by reducing emissions. They have reduced the number of accidents and fatalities on the roads. Despite their many advantages, roundabouts are limited in certain ways. Many drivers are inexperienced, and they do not know how to use the roundabouts properly. This causes many accidents on the roads. In addition, construction of roundabouts is not possible in some areas because of the geography of the region.
Works Cited:
FHWA. “Modern Roundabouts: A Safer Choice.” Federal Highway Administration. n. d. Web. 28Jan. 2014.
IIHS. “Roundabouts: These Circular Intersections Promote Safe and Efficient Traffic Flow.” Insurance Institute for Highway Safety. April 2013. Web. 28Jan. 2014.
Roundabouts USA. Roundabouts vs. Signals and Stop Signs. n. d. Web. 28Jan. 2014.
Williams, Stephen. “MALTA: Solution to Busy Corridor Debated.” The Gazette. 2013. Web. 28Jan. 2014.
WSDOT. “Driving Roundabouts: Roundabout Benefits.” Washington State Department of Transportation. 2014. Web. 28Jan. 2014.