Kent ?
> Measuring 300' is not the problem, swinging a 300' circle is, even without terrain variations and vegetation.
So, are we thinking that reflectorless EDMs are going out of fashion? The setting is a plowed field, right? Your suggestions actually work against boundary certainty. The best practice is to describe only the center of the circle and let the radius control the actual circular boundary from that point. Any surveyor who can't actually lay out a circle in a plowed field, given the position of its center, might want to rethink his or her career choice.
> I'd think tops of rods 1 ft down would be reasonably safe from farming operations.
It depends upon whether the field is likely to ever be root plowed. Root plowing goes down about 20 to 30 inches. Even ordinary chisel plowing can go down 18 inches.
how to describe
Wasn't the original question about ideas for the description, and not so much monumentation? I agree with Paul, as I originally posted, to establish a POB at the intersection of the route to get there (bearing & distance calls along established lines). Then just describe it as an arc, most likely non-tangent. Monument around the perimeter so it can be retraced. I would think the POB, and cardinal points would suffice, plus the radius point so they get the tower in the right place.
I'd prefer just to have the description reference the record of survey, and skip the metes & bounds.
Fast forward 5 yrs after the tower is up, so nobody can occupy the center. Now the land owner wants to split his property and new parcel lines will intersect this easement. It shouldn't be a problem to retrace it and set those new intersecting corners.
how to describe
> Fast forward 5 yrs after the tower is up, so nobody can occupy the center. Now the land owner wants to split his property and new parcel lines will intersect this easement.
Of course it depends upon the design of the tower. If it's a mast with a regular cross-section, it shouldn't matter whether its occupiable or not. The position of the center is easily gotten either by a reflectorless shot or by simple triangulation. Naturally, the relative position of the center of the tower to the tract boundary won't have changed, so any future "resurvey" effort will be mainly to verify that it's the same tower. As long as you can determine the center of the tower, the position of the circle around it follows as a trivial exercise.
Kent, Not Neccessarily A Plowed Field
Assume the tower is now within a chain link fence. Shooting through a chain link fence with or without a prism is a crop shoot. You do not get lucky on a regular basis.
For instance yesterday I blew proper positioning of a traverse point and had a stop sign post 15' from the setup and dead on line to a fence corner post. The rod man was standing out there without a tape to give me an offset shot. I hear the EDM beep that it had acquired the prism and I made the shot through one of the bolt holes in the post. D.S. Luck, skill not required.
Why force the next surveyor to find a way to make it work? Describe it so that you know it will work.
With a 500' circle, terrain and trees, odds are 50% or more of the circle is not intervisible with the center object.
Paul in PA
Kent, Not Neccessarily A Plowed Field
I've shot reflectorless through a chain-link fence. You have to focus in and out to make sure the beam is going through a hole then review the data to be sure you didn't hit the fence. It helps to be close. Or go above the fence. On a 3 legged tower you can pick a brace to get uniform height on all legs. Or alternatively get access to the fenced area if possible.
Kent, Not Neccessarily A Plowed Field
> With a 500' circle, terrain and trees, odds are 50% or more of the circle is not intervisible with the center object.
Well, here was one of the premises of the problem:
>I thought about monumenting the extents of the circle at each quadrant but the surrounding land is farm land and no monument will last unless I set them 2-3 feet below grade.
In other words, it's in a plowed field and, to survive, your monuments on the various disjoint arcs that will be your attempt to monument a circular boundary will be 2 to 3 feet below grade. Triangulation works perfectly well through chain-link fences. Using the tower as the monument marking the center of the easement is easily the most practical solution.
Yeah, we agree on that, but there may be a reason the location of the tower site was selected in the first place, and there may be a reason to replace it in exactly the same place if it was lost due to flood, fire, quake, etc.
Kent, Not Neccessarily A Plowed Field
I agree, Kent.
I don't see the need to make the simple complex. Here's the center, make a 500' diameter circle; put that in legal description language.
A letter sized map attached to the description should make it clear what the intent is.
I'm not sure why they need 500', perhaps for guy wires. The farmer can probably still farm inside the easement but outside the fence and around the guy anchors. There really isn't a need to monument the easement boundaries until someone wants to build an office park or housing subdivision.
Here is an example of a tower in farmland:
Walnut Grove towers
Kent, I Missed That Follow Up
Given no monuments, I would still describe it from an occupiable monument, with a visible monumented backsight, to the center passing through point on the cicle.
With field access roads and fencelines a monumentable point or 2 might be possible. Bearing and distance to the point on the circle, with a bearing and distance to the center. I hesitate to just describe a line from monument A to the object.
Paul in PA
Description of a Circle Is Easy?
I think that any description other than a center point and radius is unnecessarily complicated and would probably not be understood by a layperson. The original post never said it had to be monumented anyway.
Describe the center point from nearby property corners, reference with 2, 3 or 4 monuments nearby if necessary, and then give the radius.
Kent is absolutely correct. Any surveyor worth having his license should be able to lay the limits of the easement out, if required. In CAD, draw a circle of the required diameter, put points on the circle, go to the field, and stake the points. Alternatively, in your data collector (TDS anyway) draw a curved polyline of proper radius centered on the radius point. Set up on a known point. Stake to the polyline. In my data collector, it's just like stake to a line once you've defined the polyline using 2 points, beginning and end of the curve, on the radius and the center point.
A lot can be added to a description by supplementing it with an exhibit which depicts the subject land and conditions surrounding it. Just ensure to call to the exhibit in the text and make it a "part hereof"
Have a GREAT weekend!
CV
Kent, Not Neccessarily A Plowed Field
> Walnut Grove towers
I was on a crew that laid out one of those towers in the late '80s. Not the red and white one with the candelabra on top, but one of the plain skinny ones. It's 1,500 feet tall, if memory serves. I think they've added one or two more in the intervening years.
What I found most interesting was the function of the guy piles. I thought that they'd want the pull to be more-or-less normal to the pile axis, but it's actually along the axis. They're basically saying they can drive the pile in harder than the tower can tug on it.
Kent, Not Neccessarily A Plowed Field
Not sure in this case, but when I used to survey a lot of towers, the circular easements were usually the result of zoning regulations requiring a "fall zone". For guy wires we typically ran a rectangular easement for each guy that tied back to the leased area that the tower occupied.
This has been a hoot to read something that should be very easy. So since it isn't, let's break it up shall we.
First we all know that it takes two parts of a curve to be given to calculate the rest. I'm assuming that school and geometry hasn't changed and a circle still has 360 degrees in it. If it hasn't, there's one part. The next is the radius. So, how bout this for simplicity and easy retracement
Being a circular easement with a radius of 250 feet and fully circular in shape containing 360 degrees and being centered on an existing radio tower. Said tower being located nw 4500 feet from a 1/2" steel rod found for the southeast corner of said parent parcel and also being located ne 4500 feet from a 1/2" steel rod found for the southwest corner of said parent parcel and also having a state plane coordinate with a northing of xxxxxxxx.xx feet and an easting of xxxxxxx.xx feet and said circular easement containg x.xx acres. Bearingsa are based on the Texas coordinate system of 1983, Texas central zone. All coordinates are u s survey feet, nad83 (cors96) epoch 2002.0 per static gps data gathered on some day and processed through the opus utility via the ngs website. All distances are grid and to get surface distances divide the distances show above by 0.999999. To get geodetic bearings,'rotate the bearings recited above by 02 degrees, 34 minutes, 22 seconds.
Incomplete Description Of Circle, Kris
Frist, once you introduce SPC into a description, you must begin with SPC. Therefore before you begin with one of the parcel corners and it's SPC.
Secondly the distance description from one SPC point to another SPC must indicate if it is a grid or ground distance. Somewhere in the overall description should be sufficient data to get from grid to ground or vice versa.
I agree that a minimum of 2 ties are neccessary to be able to place the tower location on the ground once the tower is gone. Without that ability it removes the certainty that the easement no longer exists.
Last question which no one has yet asked:
"What good is a 500' easement around a tower, if the tower user has no ability to access the tower or the circular easement in the first place?"
I am fairly sure the farm owner does not want the tower user driving through the fields to the tower any which way they please.
A circular easement is only suitable for those aliens that leave behind crop circles, or possibly only a license is required for such.
Paul in PA
Incomplete Description Of Circle, Kris
Maybe it is an alien tower? The owners are planning to access their tower with flying saucers.
Incomplete Description Of Circle, Kris
My experience has been that the circular easements are required by zoning regulations in some areas. Typically they are required to prevent the owner of the parent tract from constructing habitable structures within the "fall zone" of the tower. Size of the easement can be less than, equal to, or greater than the tower height depending on the local regulations and the engineering involved.
Typical tower sites that I have been involved with required a description for the area containing the tower and equipment. In addition, easements were needed for access, utilities, fall zones, etc. Each of these were separate descriptions tied to a common point of commencement where possible.
I'm guessing that the OP only asked about the circular easement because that is what he needed assistance with. I doubt that he was intending to create a circle in the middle of a field with no means of access.;-)
Paul
Read what I wrote again. I said I was on the grid and all ties were grid. I fail to see how the application of occams razor here isn't sufficient.
It Should Read A Grid Distance Of 4500.00 Feet
Too far away and some lawyer will drop it as irrelavent.
Plus the correction for bearing varies at each point.
Paul in PA
