Can a reference mark be reset upon property owner request?

[TillaMurphs]

Can a reference mark be reset upon property owner request?

 

For a recent recovery at station TRANS I had a nice visit with the new property owner.

 

A very nice man, the owner was very interested in the marks on his property. He plans to landscape around RM2 and the Station Mark to protect them and show them off.

 

RM1 had been disturbed by recent earthwork and the owner pulled it aside in hopes that it would not get lost or damaged as more development occurs.

The owner asked if it would be possible to have someone return RM1 to its original location. Is that something the NGS would ever even consider?

 

RM1 currently looks like this:

[AZcachemeister]

Well, that's a pretty detailed report. Very nice.

 

And what were you doing in Idaho?

 

Seriously, there is probably more chance that the NGS will bluebook my GEOCAC mark.

Of course if the property owner wanted to pay to have the work done...

[68-eldo]

It would be my guess they would set a new reference mark (RM3) instead of resetting RM1. RM3 would be in a totally different position to avoid confusion.

[MarkSetter]

The best thing to do would be to contact the NGS state advisor for that area. Someone mentioned that this was in Idaho? If so, here is the contact info for the Idaho state advisor:

 

http://www.ngs.noaa.gov/ADVISORS/Idaho.shtml

[DaveD]

It is not likely that NGS will reset any disturbed or destroyed marks in the future. The goal of NGS is to deliver access to the national reference frame through the network of GPS Continuously Operating Reference Stations (CORS). There are currently in excess of 1400 CORS in the network and it is growing every day. NGS has created specifications and on-line tools to allow the surveyors in the community to reset or establish new passive marks as they require them. I regret that with the exception of accurate heights, passive marks are no longer viewed as the primary way of providing access to the National Spatial Reference System. Assuming that the NGS ten-year plan is completed on time (2018) that will be the end of passive marks from NGS. We will continue to maintain the database and distribute these data, but they will no longer serve the primary function of being the foundation of the national geodetic reference frame.

[+m&h]

Some time back we read the document on the ten-year plan, and so came to understand the diminishing importance of passive horizontal control marks. We still have some partiality to triangulation stations, just because it’s interesting to see whether the reference marks and the azimuth marks are discoverable. As long as the people in charge of the NGS database are willing to receive reports on them, we’ll send them, along with whatever elevation marks we find, knowing that they tend to have more usefulness.

 

More recently, we were among the participants in a discussion here about whether it was a good idea to reset loose disks. Our position then was pretty much in line with that maintained by NGS for many years: don’t do it. Plenty of excellent reasons.

 

However, in the case of this mark in Idaho, it seems plausible that a professional could re-set the destroyed RM, in its original position within acceptable tolerances, and describe this resetting in a recovery note. The integrity of the main station remains as it has, and NGS isn’t going to be checking up on it. (This provided that there is somebody who wants to pay for the job.) It seems that these stations are gradually evolving into museum pieces or archeological sites, so a little careful maintenance now seems less intrusive than it might once have done.

 

Some portion of our blood is being thoroughly curdled by this suggestion, of course; it sounds like the ravings of an anarchist. Nevertheless . . .

 

Cheers,

[TillaMurphs]

And what were you doing in Idaho?

Well... we were going to go to Arizona until we realized that a few regulars from this forum have expertly and completely found most of the marks in that state. So, we had to go east instead of south.

[TillaMurphs]

It would be my guess they would set a new reference mark (RM3) instead of resetting RM1. RM3 would be in a totally different position to avoid confusion.

That makes sense. I don’t think the property owner would be interested in that. He was pretty attached to his RM1 and its associated chunk of concrete.

 

The best thing to do would be to contact the NGS state advisor for that area.

Hi Marksetter,

 

Welcome to this forum and thanks for the advice. We are intrigued by your member name. Are you a surveyor?

 

It is not likely that NGS will reset any disturbed or destroyed marks in the future.

<snip>

Assuming that the NGS ten-year plan is completed on time (2018) that will be the end of passive marks from NGS. We will continue to maintain the database and distribute these data, but they will no longer serve the primary function of being the foundation of the national geodetic reference frame.

Thank you for the official answer to our question. Thanks also for the info on the 10-year plan – even though it makes us sad, it does make sense.

 

Some time back we read the document on the ten-year plan, and so came to understand the diminishing importance of passive horizontal control marks. We still have some partiality to triangulation stations, just because it’s interesting to see whether the reference marks and the azimuth marks are discoverable. As long as the people in charge of the NGS database are willing to receive reports on them, we’ll send them, along with whatever elevation marks we find, knowing that they tend to have more usefulness.

 

More recently, we were among the participants in a discussion here about whether it was a good idea to reset loose disks. Our position then was pretty much in line with that maintained by NGS for many years: don’t do it. Plenty of excellent reasons.

 

However, in the case of this mark in Idaho, it seems plausible that a professional could re-set the destroyed RM, in its original position within acceptable tolerances, and describe this resetting in a recovery note. The integrity of the main station remains as it has, and NGS isn’t going to be checking up on it. (This provided that there is somebody who wants to pay for the job.) It seems that these stations are gradually evolving into museum pieces or archeological sites, so a little careful maintenance now seems less intrusive than it might once have done.

 

Some portion of our blood is being thoroughly curdled by this suggestion, of course; it sounds like the ravings of an anarchist. Nevertheless . . .

 

Well said and well understood. Thanks m&h.

[MarkSetter]

TillaMurphs,

 

Thank you for welcoming me to the forum. Yes, I am a professional land surveyor. I work for a private engineering/surveying firm that is sometimes contracted by NGS or one of the state agencies to set geodetic control. I have enjoyed the pleasure of setting and hunting for quite a few marks during my career. That is why I chose the name.

 

As I have had the time, I have been reading through many of the posts of this forum. It's very encouraging to see the interest in finding and perpetuating the marks. The efforts of the geocachers/benchmark hunters helps the work of surveyors, which benefits the public. I appreciate your efforts very much.

 

When I gave you the advice about the State Advisor, I was unusre if NGS would be willing to reset the reference mark or not. I doubted it, but it does not hurt to ask. However, as Dave inidicated, the NGS Ten-Year Plan will channel efforts more away from passive marks in favor of adavnces in GPS positioning technology. Hopefully, by the efforts of people like yourself, the history behind these marks will not fade away into the past.

[+pgrig]

Hi TillaMurphs,

 

I recently ran into a situation similar to yours, with MY2523, an 1890 marble monument which, though uprooted during construction, still survives.

 

The homeowner said she would like to replace the monument "exactly where it had been," and asked m how come I had taken away the temporary stake I had put at the point where my GPSr indicated the mark had been. When I explained to her that a professional surveyor would need to do the work of finding the accurate position for the mark, she said she was still interested, so I contacted our State Coordinator, Curt Crowley, to check it out.

 

Curt said that the mark would probably need to be reset using OPUS, and referred me to a NH surveyor who he said did OPUS database work. He said there were very few of these people around so far.

 

I explained the situation to the homeowner, suggesting that a "replacement" would probably entail a day's work and significant cost. I have yet to hear back from the homeowner, but you never know.

 

-Paul

[foxtrot_xray]

I regret that with the exception of accurate heights, passive marks are no longer viewed as the primary way of providing access to the National Spatial Reference System. Assuming that the NGS ten-year plan is completed on time (2018) that will be the end of passive marks from NGS. We will continue to maintain the database and distribute these data, but they will no longer serve the primary function of being the foundation of the national geodetic reference frame.

 

Am I the only one sitting here, wonderin' how we're going to modify our hobby to keep up with this newfangled change at NGS?

[+Renegade Knight]

... Is that something the NGS would ever even consider?...

 

My surveyor just worked with the NGS to replace a mark destroyed on one of our projects.

 

While I can't say what criteria they use to replace a mark or not, I can say that in this case they did do just that.

[+Renegade Knight]

...RM1 had been disturbed by recent earthwork and the owner pulled it aside in hopes that it would not get lost or damaged as more development occurs. ...

 

Laws in idaho and very often the contracts that agency's let require monuments disturbed by contract work be replaced. If they know who did the work, and were willing to contact the State Board of PE&PLS they may be able to put wheels in motion to get it replaced. Or maybe not. No doubt there are nuances I'm not aware of.

[AZcachemeister]

I regret that with the exception of accurate heights, passive marks are no longer viewed as the primary way of providing access to the National Spatial Reference System. Assuming that the NGS ten-year plan is completed on time (2018) that will be the end of passive marks from NGS. We will continue to maintain the database and distribute these data, but they will no longer serve the primary function of being the foundation of the national geodetic reference frame.

 

Am I the only one sitting here, wonderin' how we're going to modify our hobby to keep up with this newfangled change at NGS?

 

I'm not worried.

 

Even given an unlimited budget, and doing nothing else, there are at least several lifetime's worth of marks out there to be hunted.

[Z15]

Curt said that the mark would probably need to be reset using OPUS, and referred me to a NH surveyor who he said did OPUS database work. He said there were very few of these people around so far.

 

OPUS stands for Online Positioning User Service

 

what is OPUS? http://www.ngs.noaa.gov/OPUS/about.html

 

OPUS is not new. I use to use it back in 2001-2002 at MDOT. I would spend a day gathering GPS info, email to OPUS from the motel and get my positions back in a few minutes and the next day we were out doing RTK. My PS was very suspicious of this, he was from the old school and any solution that took minutes instead of days triggered distrust. So I still had to send him the GPS files and he would spend a week checking OPUS. Finally after several projects he never bothered me again about it.

Edited August 29, 2009 by Z15

[Bill93]

Regarding the original post about RM1: It sounds like there is a slim chance it can be officially reset.

 

If not and the land owner insists on planting it somewhere, it would be bad for it to still say RM1 and be in the wrong place. Then someone should submit a recovery reporting the distances to the nearest 0.1 foot or better from the moved RM to RM2 and to the tri-station. This would allow someone to compute an angle (or if you have a transit you could measure the angle to the nearest minute). That info won't make it into the box score, but would tell anyone looking for the marks what happened.

 

You could also take stamping tools, X out the 1, stamp 3 (the next unused RM number). I don't think NGS would object to a knowledgeable amateur doing this for a RM that had been moved.

 

Of course the best place for the post to get replanted would be where it makes approximately a right angle (60- to 120 degrees) from RM2 when viewed from the tri-station.

[+pgrig]

Hi Mike--

 

Curt really did seem to imply that surveyors who did OPUS work were fairly few and far between around MA. Maybe he's wrong--I'm sure no expert.

 

I actually got curious and read up over the web on OPUS and CORS. Apparently we have only 6 CORS stations in the whole state (one of them quite close to me in Woburn), and New England (except for VT ) seems also to be remarkably sparsely-covered by CORS sites.

 

Now I'm curious. Suppose I wanted to keep pace with the evolution of NGS and make my own CORS observations. What would it cost me to buy a rig that would locate single points precisely (not do whole networks, or projects, of points) at professional levels of accuracy (which I gather is sub-centimeter) ? Assume I already have a beefy PC. Although price info is hard to find on the web, I get the idea it might be a $30K to $40K bill. Egad!

[Papa-Bear-NYC]

Regarding the original post about RM1: It sounds like there is a slim chance it can be officially reset.

 

If not and the land owner insists on planting it somewhere, it would be bad for it to still say RM1 and be in the wrong place. Then someone should submit a recovery reporting the distances to the nearest 0.1 foot or better from the moved RM to RM2 and to the tri-station. This would allow someone to compute an angle (or if you have a transit you could measure the angle to the nearest minute). That info won't make it into the box score, but would tell anyone looking for the marks what happened.

 

You could also take stamping tools, X out the 1, stamp 3 (the next unused RM number). I don't think NGS would object to a knowledgeable amateur doing this for a RM that had been moved.

 

Of course the best place for the post to get replanted would be where it makes approximately a right angle (60- to 120 degrees) from RM2 when viewed from the tri-station.

RMs have been moved in the past with no great harm. Check this data sheet: MT BLUE.

 

Seems when they built a new tower in 1931, they must have knocked out RM2. So the construction team set it in one of the concrete footings of the new tower, and pointed towards north. This was noticed in 1958 and noted in the log.

 

So stop worrying. Let him put is more or less where it used to be and then log a recovery noting the RM was knocked out of the ground and put back in a different place. No high priced GPS, no OPUS, no NTK, no banging up the disk, no new RM3, no worry.

 

BTW: here's that misplaced MOUNT BLUE RM2:

 

(click for larger image)

 

The station mark is under the tower off the frame towards the upper right. RM2 points off the frame towards the bottom.

Edited August 29, 2009 by Papa-Bear-NYC

[Z15]

Now I'm curious. Suppose I wanted to keep pace with the evolution of NGS and make my own CORS observations. What would it cost me to buy a rig that would locate single points precisely (not do whole networks, or projects, of points) at professional levels of accuracy (which I gather is sub-centimeter) ? Assume I already have a beefy PC. Although price info is hard to find on the web, I get the idea it might be a $30K to $40K bill.

 

Yes it could cost that much. Its not only the GPS receiver but all the peripheral equipment you would need. e.i. tripods, tribrachs, tapes, weather tools, batteries, chargers, cables, laptop with survey grade software to process the field data to send etc.

 

With survey equipment and GPS you can go cheap or you can go very expensive. There is a big range in equipment and you have to buy for what you expect to do. GPS is sort of like buying a PC, its all the extra stuff that drives up the cost.

 

.

Edited August 30, 2009 by Z15

[AZcachemeister]

After some consideration, I'm with Papa-Bear on this.

Let them re-plant it in the approximate correct location, pointing towards the station mark if they want.

After all it IS on their property.

The only harm would be if someone were to try to re-set the station mark using measurements from the now incorrectly placed RM, which DaveD has stated wouldn't happen anyway.

 

I would think a note on the datasheet stating what happened would make sure that didn't happen, regardless.

 

EDIT: for better grammar.

Edited August 31, 2009 by AZcachemeister