Roundabouts

[Eddie_T]

The state has built a two-lane roundabout on a US Hwy in my area and plans two more at the next two intersections (which are maybe 300-400 ft apart). I try to avoid it when possible. Its radius is too tight and I have trouble staying in my lane even with my Prism. I can't see the lane markings after I enter the circle and there is a curb on the right. If I were watching a car on my left and hit the curb my reaction would prolly cause me to sideswipe a car on my left. My son had to use both lanes when driving an F-250 pulling a trailer through the circle. I know an 18 wheeler has to use both lanes. Maybe my safest transit through would be to wait on the sidelines for/and follow an 18 wheeler through. I emailed the DOT regarding the problem and the plan for two more for all the good that will do.

 

[Flyover]

Roundabouts have a number of advantages, and a number of disadvantages. They're great when put in the right place, and they're a pain when put in the wrong place.

That said, there are a lot of drivers who are apparently really stumped by them and don't know how to drive in them properly, and that makes them more dangerous.

 

[Eddie_T]

Someone said they're OK once you get used to them. My comeback was what, if the other driver(s) isn't used to it. The point that dismayed me was that the tight radius doesn't permit trucks, buses, campers and vehicles pulling trailers to pass through w/o hogging both lanes. The final plan will have three of these in series with less than one mile between this one and the other two. They were to be the solution to our traffic problem. Maybe the other two can have a larger radius.

 

[Flyover]

I don't know how truck lorry drivers/drivers pulling trailers do it in England where the roundabouts are more common...they also have tighter regulations about the total lengths of vehicles, which is why overcab designs are more common there too. Here I guess you just have to slow down, be careful, and maybe try to avoid them during busy times of day. Signal extensively, make eye contact, etc.

Good point about what if the other driver isn't used to it, though that's a generalizable argument against driving entirely: you can be as safe and careful a driver as you wish, but all it takes is one reckless drunk out on the road with you...

Where I went to junior high school there were a couple notable traffic circles with radiuses that were quite huge, big enough that the middle could have accommodated a small park, except the main road in each case continued straight through.

 

[Steve123]

. I can't see the lane markings after I enter the circle and there is a curb on the right.

How is that any different than making a right hand turn at an intersection ?

 

[Snoonyb]

To me, roundabouts are a comedic act perpetrated upon the driving public, in the name of efficiency.
When learning to drive, in the 1940's, the rule was that the vehicle on the right, had the right of way.
Not in roundabouts.
You are required to signal when entering a roundabout.
Since there are no double solid lines, defining lanes in a roundabout, what are your actual intentions, in the signaling?
Is it your intent to change lanes in the roundabout?
Will an approaching driver at the 90 degree assume you intent to exit at 90 degrees, and enter, causing you to panic brake?
Since there are no dbl. line lane definitions, and you are in the outside lane with the intent on exiting at the 270 degree,
crossing in front of the driver on the inside lane, who is exiting at the 180 degree?

 

[Flyover]

To me, roundabouts are a comedic act perpetrated upon the driving public, in the name of efficiency.
When learning to drive, in the 1940's, the rule was that the vehicle on the right, had the right of way.
Not in roundabouts.
You are required to signal when entering a roundabout.
Since there are no double solid lines, defining lanes in a roundabout, what are your actual intentions, in the signaling?
Is it your intent to change lanes in the roundabout?
Will an approaching driver at the 90 degree assume you intent to exit at 90 degrees, and enter, causing you to panic brake?
Since there are no dbl. line lane definitions, and you are in the outside lane with the intent on exiting at the 270 degree,
crossing in front of the driver on the inside lane, who is exiting at the 180 degree?

In a well-designed roundabout, the outermost lane should be for exiting, and ideally should be designed with painted or in some contexts raised medians continuous from the "spokes". Not to scale; yield signs are for drivers entering the roundabout:



That way, drivers entering the roundabout don't have to guess whether they are about to get T-boned, and they can simply merge in the same way one would on a curved stretch of freeway.

Modern sensor technology might be able to detect when cars have entered the roundabout and replace the yield signs with traffic lights (maybe temporary ones: "stop when blinking" kinda thing), so the interchange can still work smoothly during heavy traffic conditions.

 

[Flyover]

I also think a lot of the disadvantages of roundabouts are the same as the disadvantages of square intersections. For example when people don't indicate before changing lanes, or when people change lanes at inappropriate times, or when people try to barge in when there isn't room.

 

[Eddie_T]

The rule for the two lane roundabout is that one cannot change lanes in the roundabout. If one is to exit at 90° he has to be in the right lane when entering. If one is exiting at 180° he must enter from the left lane, use the center ring assuming anyone entering at 90° will exit with you at 180°. If one is exiting at 270° or 360° he must be wary of others entering the center ring.

The one I am using (or avoiding) has only three ports so traveling north there are 90°, 180° and 360° options but traveling south there are 180°, 270° and 360° options. I am saying 360° but in traffic I don't have time to read the sign so I don't know if the 360° option is legal. I use an alternate route when travelling north and only use the right lane when traveling south though both lanes can be used for traveling through since there is no 90° exit.

I don't know if roundabouts are common enough that others passing through the area are familiar with them or not. People tend to drive by rote but the roundabouts require a bit more concentration than a simple intersection especially with the tight radius and popularity of four door pickups. Most illustrations of roundabouts show wide sweeping entryways whereas ours as built is quite tight.

 

[Eddie_T]

How is that any different than making a right hand turn at an intersection ?

Speed and no red-light!

 

[Eddie_T]

I think the problem with the existing roundabout is that DOT had originally designed the intersection for a red-light and the city had them change it to a roundabout after it was completed. It added another six months to opening. Since it's only a three port I think it ended up being a compromised design.

The next intersection down the road is a major intersection with a red-light. It already has a sweeping right-turn lane that avoids the light so hopefully the roundabout when constructed will continue that provision.

NCDOT has poor instructions for roundabouts. SCDOT says to approach them just as you would a normal intersection with respect to one's turn or through plans. It also says the number of lanes of the through highway continue through the roundabout. So I should be able to stay in the right lane for either a 90° RT or a 180° pass through. Since there are other impressions out there it means proceed with caution. Like a neighbor said, "I know I have the right-of-way but does the other guy know that?"

 

[Sparky617]

I lived in the UK for two years while in the USAF. They have some crazy ones over there, that make sense when you go through them, but look insane on the signs. My 10 mile drive to the base had maybe 2 traffic lights in Brackley, and several round-abouts. The round-abouts really kept traffic flowing. My town just redid a street we use frequently. There is a middle school and an elementary school entrance off of this road, and a fairly major subdivision road. They put round-abouts at both. I'm positive without the round-abouts the school and residents would be asking for traffic lights at both of these intersections. Since with the improvements to the road the speeds tend to increase. The round-abouts work well. There are many places that have traffic lights today that would benefit from a round-about. They don't take up that much additional real estate. Trucks could always drive over the paved section of the circle in the middle. It could easily be driven over without damage to anything but the lowest sports car.

 

[havasu]

Roundabouts are used as traffic calming measures. My city had two fatal accidents in this particular area in 20 years. The traffic engineer decided to add two roundabouts to slow traffic down. Afterwards, there were 6 fatal accidents in two years. Guess what... they removed those dumb roundabouts.

 

[Sparky617]

Roundabouts are used as traffic calming measures. My city had two fatal accidents in this particular area in 20 years. The traffic engineer decided to add two roundabouts to slow traffic down. Afterwards, there were 6 fatal accidents in two years. Guess what... they removed those dumb roundabouts.

Unusual for fatalities at round-abouts. Accidents tend to be minor, no T-bone or head-on collisions.

 

[Eddie_T]

I read a study suggesting that roundabouts have increased the total number of accidents. That's what scares me because I don't do fatal accidents. A mere fender bender could total my Prism.

 

[havasu]

People who usually drove down a straight road now had to slow and go around this roundabout. The fatalities drove straight into the roundabout, ejected up and over, and would hit cars head on going the opposite direction. Fog, darkness and alcohol were contributing factors.

 

[Flyover]

Eddie I think you have a legit worry. Unfortunately roundabouts have become politicized; many people's brains switch off when they enter them, but the politicization means people's brains switch off when they merely think about them.

 

[Eddie_T]

I didn't realize they had been politicized but I guess most everything is nowadays. I've noticed that back road traffic has increased so I guess others are avoiding roundabouts which will result in more back road accidents.

 

[bud16415]

Pa has become the roundabout adopting state over the last couple years. Just in my area they have added 5-6 in the last few years. They started out with single lane circles on some roads that had steady traffic but not heavy traffic and they worked well enough. The rule was once in the roundabout you had the right away and it was up to anyone entering to merge ahead or behind you safely. In theory 5-6 cars could get in there and go round and round and all traffic would be backed up. The problem I thought was the places they tried them out worked just fine as ether 2way or 4way stops for years so I never understood the need. The cost to build one was IMO ridicules at over a million bucks and all it is a circle of pavement with a fancy planter in the middle. Most of the crashes so far on these simple ones are people plowing into the center planter.



Then after a bunch of these “successful” ones they built the one we call (The Big I) it was one of the busiest places with four, four lane roads coming together. so there is an inner and outer circle with curbed gateway in and out. Keep in mind in NW PA we sometimes get 150” of snow in a winter and our plow trucks are moving walls of snow in and out and back in to the lanes and just beating the crap out of the gated curbs along with tractor trailers using the inner ring before the planter to be able to get around. When they do that they move that snow that doesn’t get plowed much into the lanes that painted lines or not you can’t see in the winter. Now for the really stupid part of the Big I one block from it on the most traveled of all the roads is a traffic light. 20-50 cars back up at that red light and come at the Big I all at once and once the first one noses in and assuming most are going straight or want to exit at 270 left this big slug stops everyone at 90 cold and that backs up. Because the circle slows the flow unlike the green light that used to be there just about the time the last one enters the light below has let the next batch in. People have learned if they are trying to get in at the 90 and want to exit right they can get off before the Big I at a Sheets station race thru the parking lot duck into Aldi’s lot cut across it and then exit back onto the road they are trying to get to. Oh by the way the Big I was like 3 million bucks and the planter in the middle is beautiful except if you look at it you might get killed and it is so high it blocks the view of who’s coming around. Did I mention it also has to comply with the ADA act. Just because they can people are riding on these roads in blizzards on electric scoter chairs, people with bicycles and even the Amish In their buggies trying to get to Aldi’s.



IMO traffic circles are the classis example of a solution looking for a problem.

 

[Eddie_T]

There are times that I think why couldn't I just be like the masses and believe the government will work it all out with time.