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How is centerline, and stationing defined?
Posted by nate-the-surveyor on January 21, 2021 at 2:38 pmDo we shoot centerline, and make all curves tangent?
Or, shoot r/w markers, and use Hwy dpmt radius, holding the r/w markers, even though this makes broken back curves, and odd road widths?
Or, a combination of these, making the curves properly, and just figure that the whole shootin match was not that accurate in the first place, so we modify the curve data, to make it pretty close, and tangent?
What is the right answer?
Thank you,
N
aliquot replied 3 years, 2 months ago 24 Members · 51 Replies- 51 Replies
I look for right of way pins – and fit the curve in under the assumption that what was planned in the office was perfect math, what was put on the ground becomes imperfect, perfect legal property lines. most of us, but not all, do that here, so of course we get pincushions that only make the public laugh at us.
maybe if you type “Kent” 3 times…
The highway boundary is a boundary like any other. Monuments control the boundary. In absence of monuments, long standing fences and the face of stone walls control the boundary.
The pavement or the center line is not a monument. Even in cases of the highway having a layout base line there is little hope of finding the base line because it was destroyed when the highway was constructed.
You only use the layout as a guide.
Historic Boundaries and Conservation EffortsHow about shoot the yellow line, and call it good?
I tend to hold the centerline monuments if they are in. If not, I use the R/W monuments to re-establish the centerline. Roads are rarely designed and/or dedicated using broken back curves and I would need a real good reason to create one were it not called for.
I start with a very close inspection of the highway plans. Too many times the base line, the project center line and the center line of the pavement are three different things. ROW markers are nice but one must recall most of them were set by contractor staff, not surveyors. Anymore it is common to find nothing but a 60D nail at the ROW change points. I tend to favor box culverts and bridges to lock in control. But, you must double check the plans on those as frequently the box culvert is set with one side longer than the other side relative to the true centerline.
I have to disagree with you, somewhat. At least in this neck of the woods, when a road legalization survey is performed the centerline of the traveled way is held as the new centerline. A road legalization survey is used to define the R/W of a long standing road whose record centerline cannot be laid out on the ground or where the road leaves presumed R/W. They are usually completed by a government agency but can be done by private surveyors. The idea is that the there are actually 2 R/W’s, the one dedicated and the traveled way created by prescriptive rights.
In our jurisdiction the law requires that long standing fences be used in the absence of other evidence. In early times it was common that a highway layout established one of the sidelines and set with monuments, courses and distances, while the other was described by width.
Historic Boundaries and Conservation EffortsGets a bit complicated out this way (Northeast). DOTs say the centerline the ROW is referenced to (construction, design, whatever) is the monument, the bounds, etc. are references to the CL. In Vermont, if it cannot be established that a road was legally returned (vote to layout, layout, surveyed return of layout) then the ROW becomes 1.5 rods either side of the EXISTING centerline. This results obviously in curves. I am however, loathed to put curves on historic ROWs where we have physical evidence. If you read any return of layout from the 1700 & 1800’s the courses of the centerline are always straight, not curved.
@holy-cow I fully agree. Having been both a surveyor and a highway designer I have seen MULTIPLE instances of right of way monuments set nowhere near the design location. As I was inspecting one of our jobs I saw the laborers using an auger pull up the stake, begin the hole, and then move a few feet to where they didn’t hit rocks or roots. I’ve seen new monuments in the ground on one side of a fence and the stake for the monument on the other. Too much trouble to lift that dang thing over the fence I guess. Unless I can find SIGNICANT differences between the plans and the “on the ground” location I hold the existing centerline as the center of the right of way and note the location of found monuments.
Andy
Right-of-way locations can depend on any number of things. What was the applicable law at road creation? What method was used to create the road? Has anything been done to modify the road?
In over 40 years I have not seen a one size fits all method in any jurisdiction. It’s like everything we do. What does the evidence tell you to do in this situation?
I’m still baffled and amazed at the concept of CL monuments. It must be awesome
If the paint line moves, (gets re painted) does the road move?
As in “It Kent be done.”?
@not-my-real-name “The pavement or the center line is not a monument.” – unless it is. Or is accepted as the monument. Some of the State and County roads here in NY were turnpikes. The right of way is still there, in spite of the road side face of the stone wall or the fence that has been accepted and called for as the right of way for in the deeds for a long while. It is customary to hang the turnpike width, often, but not always, 66 feet, on the center line of the traveled way, often the double yellow line. But, in all survey matters, it depends….
Ken
Our DOT believes that the invisible, usually unmonumented, “centerline” controls. By doing so they reject nearly every monument along the sidelines. Curiously, they establish their “centerline” from monuments that may be hundreds or even thousands of feet away from the sidelines. I believe that we were directed long ago by the courts that monuments control over math, so I almost always accept monuments I find along the sidelines. If I find monuments at or near both a PC and PT I re-establish the arc as being non-tangent, record radius curve between the monuments.
Very interesting subject because of all nuances that can come into play. I was looking at one the other day where we have a ROW dedicated by plat and a road that was pioneered in with little attention paid to that platted location. It’s been in use for 30 plus years. Clear prescriptive rights. It can be like peeling an onion. Sometimes the location can only be decided on by a court. Who has authority over the road, is it a State maintained ROW or a local jurisdiction? I’ve seen some whacked ROW location solutions done by the State that ignore every private surveyors monument set in the last fifty years. Even the State will disavow their older monuments that were set by contractors, but offer nothing by way of an alternative. Some should just be labeled “Dragons live here”.
WillyWhether you define your line; here, there, or some place else, your client will still look out there window and see the same thing; every morning.
Your best bet is to document what you did and hope that what you did was right.
Dougie
I hope everyone has a great day; I know I will!I try to hold tangent curves. I try to hold r/w mons. I try to hold C/L, both paint line, and mid of pavement. Of course, this takes time.
I consider R/W mons usually are good, for allingment, but poorer in station.
One up near MT ida, I shot all r/w mons, and C/L. Centerline wandered up to 3 feet, but the RW mons were tight. I held RW mons.
There are no “fixed answers”.
N
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