Can Continuous Flow Intersections Prevent Collisions?

Published on Aug 14, 2020 at 7:07 pm in Car Accidents.

Empty road on a hazy day

Our intersections in the United States mostly follow a traditional model. This means that all the roads meet and face a signal with four phases—two for left turns and two for going straight through the intersection. These signals can cause traffic to back up, and also create accidents when drivers run red lights for both turns and through movements alike. Is there a way to reduce traffic and prevent collisions? Continuous Flow Intersections, or CFIs, could be a solution.

Implementing Continuous Flow Intersections could reduce accidents, but there aren’t many CFIs in the United States yet. In fact, there are fewer than 50 across the nation. There are at least three in Illinois, but could be more eventually.

In a Continuous Flow Intersection, traffic signals are reduced to only two or three phases, and there is traffic constantly flowing through the intersection, which is where it got its name. These models for intersections can accommodate more vehicles because there is less time waiting to pass through the main intersection. Let’s take a look at what makes CFIs effective and how they can prevent collisions.

The Safety of Continuous Flow Intersections

While Continuous Flow Intersections look more complicated than traditional intersections, they could be a safer option to easing traffic congestion. In a research study published by the Federal Highway Administration, they found that there were reductions for all vehicles in the number of stops they had to make, the time they spent waiting to make a turn, and the time they spent waiting to go straight through an intersection when an intersection has a displaced left turn (DLT), which is one of the main components of a CFI. Pedestrian crossing is also made easier by this configuration.

One of the aspects that makes CFIs potentially safer is that there are fewer conflict points, meaning that there are fewer places where traffic crosses and fewer places where collisions are possible. A traditional intersection has 32 potential conflict points, whereas CFIs have four less at 28 conflict points. That might sound like a small safety improvement, but it actually is substantial.

For example, with the DLT system, left turns cross traffic into their turning lanes when the north-south lights are red, and when east-west traffic has a green light and is moving. Then, when east-west traffic sits at a red light, and north-south traffic is moving, the cars in the DLT lanes can continue through into east-west traffic. Since the turning cars cross traffic before the main intersection and while north-south traffic is stopped, there is less chance of collision.

Cons of CFIs

While there are many advantages to CFIs, like easing congestion and reducing the chance of collisions, there are also some disadvantages. One disadvantage of reconfiguring a traditional intersection into a CFI is that since they are bigger in size, they cost more money to construct. These updates could help existing intersections, but they would require a budget, time, and the space to complete the project, which might not be available.

Even if they are implemented, there would be a learning curve for drivers because they would not be used to the configuration. In general, people quickly adapt to the new pattern, but they would need clear overhead signs to ensure they can easily follow the new flow of traffic. The confusion can make the intersection slightly unsafe at first, but then it becomes safer as time goes on.

Another slight disadvantage is that the displaced left turns take away the ability to make a U-turn. But in Illinois, that’s not a problem because U-turns are illegal.

Prince Law Firm Can Help You

When you get into a car accident that wasn’t your fault, you shouldn’t have to deal with the financial consequences of your injuries, damages, and any lost wages. At Prince Law Firm in Marion, IL, we will be here for you every step of the way through your car accident claim. You might be hesitant to start a case because you think it will be too much to handle, but that’s where we come in. Our experienced car accident lawyer will take care of the legal side of things and recovering compensation for you so that you can focus on healing. Reach out to us today so that we can get started on getting you the justice you deserve.



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