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I came far too close to being killed at a rural intersection within the past year. It was precisely as described above, except that is in the intersection of a US highway and a State highway. Stop signs from all directions, red lights, big signs, rumble strips. Started to pull out when a semi blew through a couple feet in front of my front bumper as I hit the brakes. He never slowed one bit.
Two weeks ago I drove around an accident at a similar intersection. A heavy truck pulling a small trailer never stopped and slammed into the side of a semi that had stopped and then started to continue on its way. The semi toppled over from the impact.
Eight miles further west is one of the first roundabouts in this corner of the State. Works great. As far as I know, there haven’t been any significant accidents there. About two miles to the northwest and then another mile further northwest along the US Highway are two standard intersections where the side roads have STOP signs. There have been numerous fatalities at both intersections since the installation of the roundabout at the intersection with the State highway. during construction of the US highway route. It is painfully obvious that the roundabout is saving lives.
Never seen a four way stop sign intersection. Either roundabouts or traffic lights in NZ for the main. Often a through road with a road that crosses it will end up with two staggered t intersections so you can blow through even if you wanted.
Roundabouts way better for getting more traffic through an intersection than traffic lights, only down side to them is where one lane of traffic of dominant and then others don’t get a fair go.
It’s been my experience that the engineers that I’ve worked with at, so far, a County in NY and AKDOT, don’t want to even listen to a common sense solution until they realize what their “perfect world” costs.
Another case in point there is a “T” intersection that has a Mcd’s across from the intersecting road which has a school on it somewhere (the main road is one of the main roads through the town). People were concerned about the students going to Mickeys after school and, of course, not crossing safely (we all know it’s not the individuals responsibility for their own safety, that’s DOT’s fault). In an effort to make the intersection safer for the pedestrians, they need to update the intersection. The real culprit was insufficient sight distances, the solution – replace the now oversized electric unit that was blocking the one sight line, but there were still 3 parking spots where the parked cars could still inhibit sight, so we must purchase that triangle of property. Those three parking spaces were in an apartment complex that, by zoning, required two spaces per unit and the owner was at the bare minimum as it was, so he would potentially either lose two units or have to combine four units into two (zoning variance was out of the question, we checked). Now to me the simplest solution would be a nice shiny new traffic signal at the intersection, but the engineers, in their infinite wisdom, proclaimed that to not be a viable solution, we had to purchase that piece of property (by the way the owner of the apartments was one of the oldest residents of the town and owned a pretty good chunk, as well as the property that was being leased to Mcd’s across the street. We tried everything under the sun, even trying to buy a piece of a neighboring property to accommodate the parking issue, but the owner wouldn’t budge which would force the State into condemnation proceedings.
So what’s the cost of a traffic signal installation, maintenance and cost of electric over, let’s say 20 yrs, vs buying 2 pieces of 2 separate properties, having to follow that towns subdivision process for 2 subdivisions and getting the courts and lawyers involved for condemnation. All to obtain about 80′ of sight distance.
I don’t know what the outcome was, or if it’s still being hashed out, but I wouldn’t be surprised if the final act were the most simple solution that they overlooked.
Need I mention that they seem to think that the green book that is a policy and guideline, as if it were the holy grail, absolute must do it this way manual.
Saw this on FB and had to post it here just because it made me laugh.
- Posted by: @lukenz
Never seen a four way stop sign intersection. Either roundabouts or traffic lights in NZ for the main. Often a through road with a road that crosses it will end up with two staggered t intersections so you can blow through even if you wanted.
Do you not have rural roads that start with little traffic and no signage at all, then someone gets hurt (or someone thinks someone will), and they put a stop sign in? Or in NZ do they at that point simply put in a roundabout? The staggered T makes sense from a traffic control sense, but how in the surveying did that happen?
-All thoughts my own, except my typos and when I am wrong. Your right will be the odd four way rural one on low volume roads but nearly always one road is dominant and the other one gets two give way signs(similar to a yield one I’m guessing) splitting it up. Also not a huge number of plains in NZ which also naturally prevents the four way problem as roads follow ridges and valleys.
Roads ownership a bit different in NZ, all standard roads were laid out 1 chain wide (20.12m) and the land is all crown land (rights of way here are just for shared private driveways and the odd private road). With publicly maintained road the land is owned by crown (state). If traffic volumes warrant an offset intersection the local council or government takes the land under public works legislation.
All radical title to land in NZ is held by the crown, except for some very small amounts of indigenous land. Private owners have an estate in fee simple but not radical title to land.
Roundabouts are mostly for urban intersections (50km/h speed limit) but we do have large radius ones on our State Highway Network in 100km/h rural areas. So sign, offset intersection, roundabouts and then traffic light the hierarchy.
USA decided to take on Europe??s design on intersection. Some how we are behind on n traffic safety. Txdot has taken on doing more Roundabouts since it safer then other intersection types. Truck apron is a name for the area at the rolled curb. When I did my first roundabout, I kept wonder why that section was as thick as the travel lane. It is for tractor trailer to have room to go around. Which should have them reroute to another straighter street. We are seeing more of these on city street here in Dallas.
- Posted by: @holy-cow
Driver’s education is offered through most high schools and is a big money maker for private firms.
They sure are doing a crappy job…
- Posted by: @jph
That one isn’t bad. But you should see the one’s they’ve built in NH. Very tight circles, pretty much every tractor trailer has to ride up into the center, which might be the reason why it’s sloped granite curb and concrete in the middle. Still not right, in my opinion
That is the design of roundabouts, for trucks to drive over the mountable curb. That isn’t a pedestrian sidewalk in the middle! Roundabouts are far better than 4 way intersections, because they eliminate higher speed collisions. You’ll at most get a side glance impact at 20 MPH instead of T-bone at 50 MPH. Plus they keep traffic moving when there is little traffic, like at night. No need to wait 2 minutes for a traffic signal to turn green for you.
@dave-karoly Yes, my sister lives off Simpson Lane, so I know that one well. I saw another round-about I think was off Hwy 20 that had separate merge lanes for right turn traffic. That design created a lot less traffic conflicts within the circle.
- Posted by: @acd-surveyor
@dave-karoly Yes, my sister lives off Simpson Lane, so I know that one well. I saw another round-about I think was off Hwy 20 that had separate merge lanes for right turn traffic. That design created a lot less traffic conflicts within the circle.
That one is at Route 53 which runs south to the east side of Clear Lake.
@dave-karoly Yep, I think that was the one.
@acd-surveyor I??ve driven 20 from Williams to 101 so many times I think I can do it blindfolded.
@jph I know the one you’re talking about. It IS a little tight, especially on a major east/west truck route. I wish the next two intersections heading east into Keene were made into roundabouts too, but much bigger.
I’ve done a couple of roundabouts in Carmel. They are not fun to do. You can lay one out horizontally fairly easily using the wizard provided with C3D, but each edge of pavement has to be profiled and tied together, so changing one profile impacts more profiles. I believe that you can dynamically tie your profiles together using SincPac, but not 100% sure.
Part of designing these things requires that you run turn simulations. If you’re in a residential area you can maybe get by with using a fire truck, but typically I’ve used a WB-52 at a minimum. You also look at a straight path through at the speed limit, but realize that people do exceed that speed, therefore the roll curbs in the middle. Yes, the concrete is thicker, usually 9″, in this area to account for semis to run across them.
As a driver, I love them most of the time. I don’t live in Carmel, I’m on the south side of Indianapolis, but their popularity continues to grow in this town, and I have probably close to ten of them within a few miles of where I live. Occasionally I am behind a driver who comes to a complete stop with no other vehicles in sight, or is afraid to enter unless there is no one else within 100 yards of the circle. Overall I think they are great for all the listed reasons.
- Posted by: @dmyhill
eliminate T accidents (which are some of the worst for fatalities)
I was told by our county’s recently-retired Principal Civil Engineer that this is the main reason that Caltrans no longer funds 4-way stops on county highways. If the county wants state funding, they have to use roundabouts instead of 4-way stops.
@richard-germiller Yep! What the auto racing world refers to as “friendly curbs” they aid in rotating the car without upsetting forward bite. :). Jp
The first LS that I worked with lived near this thing and hated it. The thing is huge and not exactly round for a roundabout, and I think he came into from the southeast and exited south every day which probably ends up being slower than a 4-way stop. I worked on a project where I had to pass through this thing (going same way as the boss) most days for a solid year and it did get to be annoying.
Occasionally I am behind a driver who comes to a complete stop with no other vehicles in sight, or is afraid to enter unless there is no one else within 100 yards of the circle.
I love roundabouts. I just wish they would teach people who to use them. The stopping thing kills me, as well as the fact that no one signals to leave them. I have to go through four or five (depending on which my path) to get from my small town to the highway into Portland.
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