Basis of Bearings

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kwilson
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Basis of Bearings

Post by kwilson »

Our office recently submitted a Record of Survey to a County where we frequently work. They have a new County Surveyor with an LS in the 9000 range. One of the many redlines had to do with our Basis of Bearings. I previously created this document as a means to show County Surveyors what I believe to be acceptable methods of establishing a basis of bearings. While not trying to be dogmatic or unreasonable, the intent is to help all understand what can be done which in turn will minimize restrictive points of view on this subject. So i am providing this document as a discussion topic for the forum and for anyone who wishes to use it or edit it for their own purpose.
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hellsangle
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Re: Basis of Bearings

Post by hellsangle »

The late Gene Lockton (1973 CLSA President) used to mess with the County Surveyor's mind.

Thought you all would enjoy his humor.

Crazy Phil Surveyor to Recorder
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khuerth
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Re: Basis of Bearings

Post by khuerth »

While my number is in the 9000's also, I still have an opinion.

I have always used a "record bearing" as a Basis of Bearings, but I would argue you could use any two identifiable points as your Basis of Bearings on a map (monuments or even your control).

8764 (b) "Bearing or witness monuments, basis of bearings, bearing and length of lines, scale of map, and north arrow."

This section doesn't state it has to be of record, just shown on your map. After all a Basis of Bearings is just to tell the next surveyor what you based your bearings on, right? While the CEAC Guide RS Checklist does state "Basis of Bearings: map of record, celestial observation, State Plane Coordinates or County Surveyor's records" I don't think that is enforceable by the PLS Act.

Side note: What does "EK 12" stand for in your old logo? (I have retraced numerous surveys of yours in SLO County, you do good work, thank you).

Kyle Huerth
Kyle Huerth, PLS
Orcutt Survey Company
Edward M Reading
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Re: Basis of Bearings

Post by Edward M Reading »

Basis of Bearings are over-rated.
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San Luis Obispo
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Peter Ehlert
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Re: Basis of Bearings

Post by Peter Ehlert »

Edward M Reading wrote:Basis of Bearings are over-rated.
+1
Peter Ehlert PLS 5116 (retired)
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Re: Basis of Bearings

Post by Peter Ehlert »

I suggest you search this forum for the post "Basis of Bearings (2 Record Monuments)" dated 10 Jun 2015

as I stated my personal opinion on the subject:
"off topic a bit, but:
I think the "Basis of Bearings" statement is outdated and unnecessary.
It had a place when surveys were based on compass readings or astronomical observations.
Modern day (my lifetime) all we need are a few durable monuments (or other objects), and the relationships between them and the points or lines in the survey. Coordinates/Bearings and Distances/Cosmic Vibrations... they all work
Every darn one of us can translate and rotate to any darn record or imaginary basis of bearing/coordinate system and perform our tasks. (If someone Can Not do that then apply for a job as a hamburger flipper.)

so in short: If I can touch it and calculate the relationship to the survey it is a Done Deal."
Peter Ehlert PLS 5116 (retired)
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Ian Wilson
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Re: Basis of Bearings

Post by Ian Wilson »

Ken, If I can be of assistance, please let me know.

Phil, as long as the first statement sits atop two fixed, findable points, both of those statements are quite acceptable...even properly irreverent. I love those bit placed on maps.

Kyle, well said. The basis of bearings does not have to be record, nor does it have to bear any semblance to bearings provided by a compass. If I choose to label a northerly bearing as "N 90° E" for my map, then that is so.

The basis of bearings serves no purpose except as a calibration between the record survey and any survey made by future surveyors using the record. By finding and measuring between the two fixed points, future surveyors can relate their work to that of the surveyor filing the record, even if the units of measure are completely different. As long as the two points established as the basis of bearings are recoverable and fixed...on with the show!

Interestingly, the line established by the split of a pair of curbs is not terribly well fixed but the line between location of a star on a particular date and time and a fixed point on the ground is.

My 2¢...
Ian Wilson, P.L.S. (CA / NV / CO)
Alameda County Surveyor
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Re: Basis of Bearings

Post by DWoolley »

Peter Ehlert wrote:I suggest you search this forum for the post "Basis of Bearings (2 Record Monuments)" dated 10 Jun 2015

...
I think the "Basis of Bearings" statement is outdated and unnecessary.
It had a place when surveys were based on compass readings or astronomical observations.
Modern day (my lifetime) all we need are a few durable monuments (or other objects), and the relationships between them and the points or lines in the survey. Coordinates/Bearings and Distances/Cosmic Vibrations... they all work
...."
+1

DWoolley
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Re: Basis of Bearings

Post by btaylor »

Peter Ehlert wrote: I think the "Basis of Bearings" statement is outdated and unnecessary.

Agreed, so that may make me a "+3" at this point in the thread.
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Re: Basis of Bearings

Post by Edward M Reading »

It's all just angles. Spin them any way that you need to.
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Re: Basis of Bearings

Post by Gromatici »

One problem I've run into is a certain county wants you to explain in your BofB statement that you didn't find the same character monument for your basis of bearings as the map you're referencing. So if the map had two 2" inch pipes with Tag#12345 at both ends and you found a C-nail at the surface that was accepted later by another map, for one of those points: They want a paragraph of explanation regarding your basis of bearings. They really want some details...............I think it's just getting out of control on the amount of detail folks want and it's not doing the good that they think it is.
Eric J Ackerman, PLS, RPLS, CFedS
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hellsangle
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Re: Basis of Bearings

Post by hellsangle »

I was going to bite my tongue . . . '

but you know me: Surveyor to Recorder!
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Peter Ehlert
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Re: Basis of Bearings

Post by Peter Ehlert »

hellsangle wrote:I was going to bite my tongue . . . '

but you know me: Surveyor to Recorder!
+1
Peter Ehlert PLS 5116 (retired)
kwilson
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Re: Basis of Bearings

Post by kwilson »

Thanks all for your comments.

Kyle the EK stands for my two sons Erich and Koen and the older one was 12 at the time i created the LOGO. I took it loosely from a LOGO that Tom Vaughan made for his company.

And regarding the mention of the 9000 number i was not trying to discredit our newer surveyors who we appreciate as the ones who will be doing the bulk of the work in the future, but it would be a good idea for newer surveyors to consult with some who have been doing this a long time before making up things that they may not be able to support. I remember learning a ton from two of the long time County employees who checked maps in San Luis Obispo County, James Granflaten and Jim Estrada.
Randy Mayer
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Re: Basis of Bearings

Post by Randy Mayer »

Peter Ehlert wrote:I suggest you search this forum for the post "Basis of Bearings (2 Record Monuments)" dated 10 Jun 2015

as I stated my personal opinion on the subject:
"off topic a bit, but:
I think the "Basis of Bearings" statement is outdated and unnecessary.
It had a place when surveys were based on compass readings or astronomical observations.
Modern day (my lifetime) all we need are a few durable monuments (or other objects), and the relationships between them and the points or lines in the survey. Coordinates/Bearings and Distances/Cosmic Vibrations... they all work
Every darn one of us can translate and rotate to any darn record or imaginary basis of bearing/coordinate system and perform our tasks. (If someone Can Not do that then apply for a job as a hamburger flipper.)

so in short: If I can touch it and calculate the relationship to the survey it is a Done Deal."
+2

Randy Mayer
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Re: Basis of Bearings

Post by mpallamary »

Years ago, I was retracing a sectionized boundary in some very rough country. I found a geodetic control station with good coordinates on it. I set up and took a solar and I was off and running. Prior to the widespread use of GPS, I did all of my work using a solar BOB. When I surveyed in New England many years ago, we used magnetics because of dense forests and limited technical gear. It all worked very well. Times change as does technology.
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hellsangle
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Re: Basis of Bearings

Post by hellsangle »

Ahhhh point well taken, Mike!

Many years ago, Roy Minnick compiled a bound book: Laws for Surveying in California.

The was a section regarding duties of a County Surveyor . . . and one of those "duties" . . . was all his/her surveys were to be performed on True North.

I used to take a solar and relate it with a mapping angle to my survey's Basis of Bearings.

If your survey is on True North or Astronomic North . . . all one needs to retrace is one point and you'll find the remaining points. I did that in an old 1920s subdivision that had Solar basis of bearings. We found one "retracement" point . . . assumed it's position . . . took a solar . . . and made a tie for the original monument. The original monument was off the road, (on the downhill side), and buried over three feet! Voila: A "one-point tango" with the sun (original basis of bearings) and original monument. Another resurvey-point almost 700 feet away . . . fit bearing by about one minute.

A solar is a quick 'n easy. Just need to have clear weather.

Have a nice Memoria Day weekend, cousins.

Crazy Phil - Surveyor to Recorder
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Re: Basis of Bearings

Post by mpallamary »

Many thank! You also!
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Ian Wilson
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Re: Basis of Bearings

Post by Ian Wilson »

Ah, Phil! Memories of setting up the T-16 with solar filter and listening to the Radio Shack Time Cube to get those Solar's in. I got so I could do a Solar from set-up for calculated bearing in 15 or 20 minutes. Memories...

Of course, because the position of the Sun, given a location on the surface of the earth and a precise time, can be accurately calculated, this whole idea works. The Solar Basis of Bearings is based on two fixed points: the one you're set up over and the big, flaming ball in the sky.

How many others sat Jack Sand's brilliant Solar Observation Workshops?

Good memories, Phil! Thanks!
Ian Wilson, P.L.S. (CA / NV / CO)
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steffan
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Re: Basis of Bearings

Post by steffan »

This reminds me of the time I received a phone call from a USFS surveyor who was having trouble getting a county surveyor to understand that a boundary of a survey based on true north will and should mis-close by the amount equal to the convergence of meridians.
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Re: Basis of Bearings

Post by PLS7393 »

Yes yes and yessssss!
+4, 5, & 6

I do think a B.O.B. between two known points is helpful allowing the next surveyor to retrace your survey, and not make up his own (random) B.O.B.
In doing that you may be creating a gap or overlap if not holding record angles per the senior deed (as I'm finding on a current project) and causing some large issues. Splitting curbs has been used many times over the years as best evidence being the original intent, and its a good thing now we are doing a RS to document.

PS Phil, your not that crazy, or I have began to follow your footsteps!!!
Keith Nofield, Professional Land Surveying
PLS 7393
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