Real life road design brain teaser 1

[joengr]

I have a road that was a one-way but will now be changed to incorporate 2 way traffic. The road is very very old and has been used by the public as a two way road forever. In order to avoid lawsuits we are changing the signs to specify that the road will now be a legal 2 way road.

The road has some tricky geometry. It is very old, is 18 feet wide, has no shoulders, is bordered on one side by houses and a brick wall which come to the edge of the pavement and is borded on the other side by a 10 foot shear drop-off which was cut in order to make room for train tracks. All of this is in the Railroad right-of-way.

I found an exception from FHWA allowing 9' lanes since the road is a low volume, low speed, local urban road so this will give me a 9' lane in each direction. I also found an exception allowing me to have no shoulders which is good because no shoulders exist for this road.

My next obstacle invovles the 10 foot drop-off. There are no railings or barriers. The public is accustomed to driving under these conditions in both directions. I cant really install anything since there is no room and it will take either years or eternity to get the Railroad to agree to any construction here.

My questions is: Do I have to put something here since I'm changing the signs of the road to make this a 2-way road even if the public is accustomed to using it as such? If so what can I use that will not require Railroad permission or take away from my lane width?

 

[Ron]

If you don't design guardrails for this condition, you would likely be guilty of negligence. By any stretch of the imagination, this requires guards. Further, given the geometry, I would question allowing this to become a two-way roadway.

Who has responsibility for the maintenance? Is it county or state controlled? Check with your state DOT for minimum design standards.

I know you have found exceptions to many of the requirements, but finding exceptions doesn't necessarily constitute good engineering judgment. Be careful about that.

Keep in mind that though it is a rural, low traffic roadway, it will still get any and all kinds of traffic. Under current vehicle width limitations, two large trucks would have trouble passing each other on this road.

Further, you indicate that "the locals" know how to maneuver the road...well, you'll get non-locals who don't know the road...you have to consider that as well.

There are many ways to establish a barrier on the open side. Consider a few of them. You have an obligation, assuming you are a licensed professional engineer, to protect the health, safety and welfare of the public. If you allow this to go forward without raising flags, in my opinion you are not doing what your are required by law to do.

Stop looking for the exceptions and do what's right.

You indicated you are avoiding a lawsuit by changing the signs to fit the use....I think you are inviting a lawsuit by not closing a potentially unsafe roadway or designing out the deficiencies.

Good luck.

 

[Debaser]

I think Ron's got it covered.

At the moment, anyone who (ab)uses this road as a two-way despite, I assume, clear signage will essentially be doing so at their own risk. Once you make this route officially two-way, then those law abiding users who have not driven this as a two-way, and strangers to this site, will use it in the same way as any other two-way road (i.e. without thinking too much).

Therefore I think it would be up to you as the Engineer to act as if this is any other 'new' road and do what you can to save users from themselves.

 

[Debaser]

Would it be possible to give a GoogleEarth/StreetView type location of this site?
I know there's got to be a balance with respect to confidentiality of answers/queries on this site, but since we now 'have the technology' it can be good to use it.

 

[ACtrafficengr]

I'm not a lawyer, but I suspect your liability risk is higher if you make it two way than if you don't.

Disregarding what would happen if someone fell on the tracks as a train approached, a 10 drop-off is high enough to be fatal at any speed, and I couldn't in clear conscience allow two-way traffic that close to it.

To discourage wrong-way travel, I would narrow the road to 12-14 feet by installing a guide rail. This would also give you some room for the guiderail to deflect when hit.

Yes, I understand about railroads and their review times, but as long as you have a plan in the works, you have some defense against liability.

"...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail." - Wm. Phelps Eno, ca. 1928

"I'm searching for the questions, so my answers will make sense." - Stephen Brust

 

[dik]

You might be able to put barriers at the edge and have traffic yield to oncoming traffic where the road narrows down (single lane). I've seen this done in a few locales where there is a very narrow bridge.

Dik

 

[joengr]

Thanks for all the help. The first time I took a look at the situation I only had time for a quick review and drive-through. This morning I went back and walked the road and noticed a few things I missed before. The road is actually only 18' at the wide end. The rest varies between 13'-15' with a section narrowing down to only 11' so two lanes is out of the question. Also I think I will need to add guard rails.

So now my situation changes to: How do I create a one-way street for local traffic and still allow the occasional tractor trailers to use the road as a 2 way? The trucks have to do this since this is the only access road to a commercial lot at the end of the road. I cannot put in an alternative truck route and the trucks cannot access the lot from any other direction. I was thinking some kind of signalization that would shut off access to the road while the truck is coming down it the wrong way, kind of like flashing lights or crossing arms that come down at railroad crossings. Any ideas?

Thanks again for all the help. I am working with what seems to be a ridiculous problem, have no real funding to fix it, and am limited in knowledge since I have only been out of school for a few months. Any cheap ideas (or ideas that will keep me out of court) are extremley appreciated!

 

[Ron]

joengr...you are to be commended for trying to get help beyond what you have in your office. We can be a little harsh at times here in the forums, but most of us have seen how badly these things can turn out and the intent is to help you avoid those problems.

You do, indeed, have a significant problem. I'm not sure of the character of the commercial business served by this road, but is there a possibility that such access for tractor-trailer traffic could be restricted to late night or early morning? I agree that signalization is necessary in any case. Who could trigger the signal? Do you want to let a commercial entity control the access for a public road? Not likely. Signalization would have to be timed or triggered by a single use device...but that's difficult to implement. Timing would be a better way, but then you'll likely restrict the commercial activity...if it affects their business, they'll sue!

Is there a possibility of constructing an alternate route for the commercial access? Yes, that's expensive, but could be the proper solution.

Have you enlisted the commercial group to help solve the problem? You might consider this along with having an open public meeting to discuss the dilemma and the need for a safe solution to the issues.

[highlight]As debaser said, it would be helpful if you could post the coordinates or a link to the site in google earth. Maybe it would help us to offer you some better advice.[/highlight]

I hope you're not the only one in your office working on this. That's an unfair position for your employer to put you in, if so.

 

[joengr]

The address is North Railroad Street in Phenix City, Alabama. The problem area is between 13th Avenue and 16th Avenue. The business is at the west end (16th Ave.) of the street. There is an access road in front of the business but tractor trailers cannot use this due the steep grade here. If they try to drive over the tracks here they will bottom out and get stuck. As of now they have to come down South Railroad Street, turn onto 13th Avenue and then onto North Railroad Street to come into and out of the business. I've looked at redirecting the trucks through the surrounding streets but the intersections and lanes are too narrow and there are low hanging powerlines all over the place.
As you can see in the picture North Railroad street is bordered by houses and the train tracks. Some houses are almost built right on the street. The train track side looks as though it has a gentle slope in the picture but I assure you it is more like a drop-off.
Help and funds are very stressed in the office, so again, any help here is very much appreciated. I know getting a good feel of the situation from a picture is hard so let me know if you have any questions about the layout of things.

 

[Debaser]

I think dik's suggestion of having a yield part way along Nth. Railroad Street would have worked if the road was the other way round. That is it was wide enough to accommodate two HGVs at the start and had decent visibility along its length (see sketch for my initial thoughts before seeing the site).

I assume at the moment large (articulated) vehicles have to wait on the section of 13th Ave. south of the railway tracks and wait for other vehicles to exit Nth. Railroad Street first, before turning left into it?

 

[Ron]

I would consider the following three options:

1. Widen N. Railroad St. from 13th av to 16th av, adding curb and gutter and getting easement from railroad for drainage structures. Expensive option considering the only traffic from 15th to 16th is for one house and the commercial property.

2. Rework the grade at the 16th av crossing, raising the grade on the north side of the track, smoothing the grade on the south side of the track and adding a 2-inch overlay to S. Railroad for a distance of 50 feet on either side of the 16th av intersection in the westbound lane. This should stop the bottoming issue. I would also barricade N. Railroad from the east end of the commercial property to the 16th av intersection, not allowing any traffic on N. Railroad at that point.

3. Widen N. Railroad from 13th to 15th, barricade at east end of commercial property and rework grade at 16th av as noted. Not sure what the right-of-way width is for N. Railroad, but there's room to take enough by condemnation and eminent domain along the north side of N. Railroad from 13th to 15th.

The sideslope on the south side of N. RR st. doesn't look so bad from 13th to 15th....from 15th to 16th it is not workable without fill and drainage structures.

Do you work for a private firm or for the City/County?