I did a gravity loop in 2010 from the Colorado School of Mines basement to the top of Mount Evans once.?ÿ
Does that count?
Washington has an amazing number in the CBL list-you have it easy.
Iowa has 2, last measured 28 years ago, and the one in the middle of the state (2 hour drive for me) has the 0 mark destroyed and no 100 ft mark.
One sec while I start a thread about how some joker pincushioned me over .2
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@bill93 The Sand Point baseline has a unique art installation. https://en.wikipedia.org/wiki/Straight_Shot
Over the years, the park has been developed around it and hence vegetation envelops the line of sight.?ÿ
I know this kind of thing varies by area but those kind of measurements would be unheard of in my area. ?ÿA few hundredths ?ÿover a half mile? ?ÿA property corner of 0.2??. ?ÿNot going to cut it around here, more like a few feet on section and 1/4 section corners and a foot or so on lot corners. ?ÿIn my opinion you are being over critical. ?ÿI can only dream of half the surveyors doing that good of work around here.
Very windy day.......
Are you talking about recent subdivisions??ÿ It's quite common for older plats around here to have some self-inconsistencies and inconsistencies with monuments on the order of a foot.
But I think most recent ones are good, as the CAD-generated plats close to the expressed precision and the few replacements I've seen on them are close.
I??ve seen newer stuff that didn??t check much better than 0.2??, it all depends on who did it.
Stick a magnet to the top of those bars. They "come to life".
N
?ÿ"I get 2650.04, another surveyor 2650.08, another 2650.06 feet."?ÿ I don't need another surveyor, I get 2650.04' now, 2650.08' a few years ago and 2650.06 a few years before?ÿthat.?ÿ
Went to the local baseline (Hillsboro, OR). A highway sign had been erected smack in the middle of it, making it impossible to use. Started making calls to the County Surveyor and DOT survey department.?ÿ The sign had been there more than 6 months, no one had reported it. DOT policy was to visit baseline before every new project or every 6 weeks, whichever was less.?ÿ
Went to baseline near Tulsa, OK. Completely overgrown. Some of the trees on line were 6" in diameter.?ÿ?ÿ
We certainly are capable of making more precise measurements than that, but really who cares? We could spend more time measuring and more money on equipment, but it won't make any difference to our clients, their neighbors, the public, judges, or anyone else.?ÿ
I dont see a reason to either drive up your clients cost, or reduce your profit for the sake of precision that only a geomatics?ÿ engineer would care about. What is important is developing procedures that catch and eliminate blunders.
Edit:?ÿ of course if your practice includes high precision engineering or geophysical measuring then the above doest apply.?ÿ
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What is important is developing procedures that catch and eliminate blunders.
Very much agree. Unfortunately there is a not-insignificant number of surveyors who (a) have no procedures in place, (b) do not understand error analysis and blunder trapping, nor the capabilities of the technology they use, and (c) could care less about it.
Then they slap a generic statement about how their work conforms to statutes concerning traverse closure or relative positional precision, without ever even performing any analysis of their work. The only way to find out what they really did is to call them.
Years ago I didn't really understand why we had to provide adjustment reports, raw data and reduction narratives as deliverables to certain public entity clients, but gradually figured out the above. While those surveyors may never win big-ticket work they sure can wreak havoc in the public record.
"We have become very good at measuring our mistakes more accurately."?ÿ?ÿ
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I get the argument that the sky won't fall over two tenths, but we differ after that.
There is no reason not to do better with any remotely modern equipment and sound procedure. We aren't talking about wrapping 16 angles and chaining four times. If you are doing basic error detection you will catch 0.2' in a half mile. You almost have to work harder to slop it up that much.
The big issue is no original or at least quasi-original monuments set by the platting surveyor. To resurvey section lines remote to the lots each time a new lot is monumented is inviting error larger than necessary.
Set the corners for the subdivision before any lots sell, that is the key. Waiting until the infrastructure is installed is rational, but leaving lots unmonumented until a sale is not good practice, now you have whoever is hired doing what amounts to the first survey.
0.14' along a far away section line becomes 0.2' at the lot corner, who saw that coming??ÿ
These lots should be surveyed together at least once and it should be the surveyor who signed the plat.?ÿ
Imagine, you buy a lot in a Subdivision, there are no monumented corners, only paper ones. I won't do that.?ÿ?ÿ
Having them in the CBL list is one thing...actually being able to use them is another...any that are on an airport have become much more difficult to use.
@rover83?ÿ ?ÿ"Blunder Trapping"?ÿ Now that's a good phrase I can use to explain those meaningless measurements I make that have nothing to do the actual survey.?ÿ Thanks.
But why worry when you don't match the last surveyor by 0.2' in 1/2 mile. Are you going to reject their monuments, or tell your client that there is a problem?