GIS Dilemma . . .

[hellsangle]

I work in a County whereby copious original monuments (and bench marks) do not have hand-hole access covers, (i.e. standard street mons.). Because of such, every overlay or utilities projects play Russian Roulette with the remaining monuments (bench marks) and over time - precious few remain.

I have suggested contacting the County GIS professionals and get a “Monumentâ€￾ layer so that all members which employ the GIS database, (Cities, County, Utilities) know roughly where these roughly monuments reside and attempt to find and preserve ‘em. Is this a bad idea?

Because their “metadataâ€￾ contains State Plane Coordinates and/or Lat.Long . . . some surveyors are of the opinion that this is dangerous (to our profession?) and may be considered “practicing land surveyingâ€￾. Let me ask a stupid question: Would a professional surveyor solely rely upon metadata in a GIS database for establishing boundaries or for that matter - elevations? (For the latter, think: “City Bench Mark; Top of fire hydrant; City datum elevation 47.43 feet M.S.L.â€￾)

The only purpose of this layer is to “inventoryâ€￾ monuments in hopes of preserving monuments! Such a GIS layer would aid the License Land Surveyor in knowing if a monument exists and its’ pedigree. It is understood that the metadata is not “survey gradeâ€￾ accuracies, save, in those few instances whereby they have such accuracies.

Every time the GIS professionals attempt this task they are fought by threats of “practicing land surveyingâ€￾ and a “BPELSGâ€￾ complaint.

An analogy may be two parties are performing a lot line adjustment. The grantor is on his/her deathbed and wish to “clearâ€￾ an encroachment. The grantors have a loan on their property having a loan to value ratio of about 20%. When the heirs take title and sell the estate . . . the loan will be “clearedâ€￾ for the grantee.

Now, I hope I’m not gettin’ you all too confused . . . but in the above hypothetical lot line adjustment - it may be against the law not to reconfigure all the Deeds of Trust - but the “practical sideâ€￾ says it will be fixed in a short time. (And all parties acknowledge the potential for an illegal subdivision should one default.) In the hierarchy of resolutions, isn’t the “big pictureâ€￾ - to fix a situation . . . and “ . . . leave the campsite in better condition than foundâ€￾?

Same thing with the above-described GIS situation.

Can anyone offer some advise to those of us that do not want the campsite to go to hell in a handbasket? Those that believe “the-law-is-the-lawâ€￾ is liken to being a witness to an avoidable train wreck and do nothing about it because “the law is the lawâ€￾.

Your thoughts, please! Marti?! Evan?! Ian?!

Phil - Sonoma

[NickL]

I think it's a fantastic idea, Phil. The Agency could easily set conditions that would generate a list/map of monuments within the project area that the contractor must preserve.

I feel that inventorying monuments in a GIS has a similar level of "risk" (if you will) to the Assessor's GIS showing property lines. In that case, the Surveyor knows she must visit the field to collect the data needed for her survey; the same goes for the monument GIS layer.

[dmi]

A licensed land surveyor needs to be involved, not just cuz. There is some level of professional judgement needed to PROPERLY identify WHAT is a monument. It is a little more complex than pulling a bunch of tract maps and tagging C/l mons to a database.

I do agree that a monument layer would indeed be helpful and it is something that ought to be a part of every county gis. Along with knowing the monument was there when the GIS data was collected. it would be nice to have complete character of monument descriptions as part of the inventory.

Would a GIS professional recognize straddlers, I wonder?

[Lee Hixson]

Dane brings up a good point, that there would be times that an LS would certainly be able to offer good input into the process. But is it practical? I don't think so. The only way that would work is for there to be an LS physically on site during the whole operation, thus blowing the budget. Right out of the gates you're probably shooting yourself in the foot to have an LS in your proposal to the county.

I am fully behind the idea that a GIS team locates monuments--or potential monuments--at an "inventory level" of accuracy. I can't tell you how many times, how many hours, how much frustration I've endured in my 30 years, on my knees, car whizzing by, digging up metal junk and cursing the county for not preserving the monument that was supposed to be nearby.

I say you (all agencies) should do it. The insight and judgement of the individual LS then comes into play later on, when it's time to do a survey and evaluate said GIS locations. And, to make it patently clear, why not just report the coordinates to the nearest tenth only, or perhaps to the nearest foot? That is a huge up front clue to everyone that it is not to survey grade accuracy.

[Ric7308]

I believe there is nothing wrong (actually everything right) with a GIS system containing an inventory layer of survey monuments that is comprised of data that is solely supplied by land surveyors.

i.e. point symbols that by clicking provides a PDF of a Corner Record

[hellsangle]

and thank you for your thoughts thus far!

We can probably get an Elle Esss from DPW to supervise 'n control coords.

Lee I like your idea . . . truncation! Even an idjut would recognize truncation as being a "pointer" to the point. Like deed courses are to deed intent. To reiterate - who would use a GIS to survey by?!

Thanks gang . . . and keep 'em comin'!

Try stay outta the sun today!

Most appreciatively,

Phil

[pls7809]

LA County, on their website, has a GIS with triangles for corner records and purple dots for County Field Notes.

http://gis.dpw.lacounty.gov/landrecords/

Not sure if this link will take you there directly or not, but once you get in to the page there is a "Click Here for Map" and if you follow that and zoom in you will see the dots and triangles. Click on one of them and a link to the field note or CR comes up. Also if you click in a colored area, you will get a link to a Tract, Parcel or RS Map PDF.

[Matt Cunningham]

I think it is a great idea Phil. If I understand correctly, the GIS will be compiled from record data and not from field measurement? Even if the monument locations are collected with a handheld in the field, and the positions shown in the GIS, it is still better than having no record of the location at all. It doesn't appear that there is any intent to make a determination of what the monument represents, only that one may exist in the area. If my understanding is correct, I see no need to have an LS involved.

We have lost countless monuments in our area due to construction/re-construction activities. If there was an easily accessible database showing the potential for existing monumentation in the area, we may have been able to preserve many of these points.

CLSA has a Monument Conservation Committee right now that is developing a program to engage the municipalities to be aware of the problem of loss monumentation. Your idea seems like a great way to resolve the issue.

[LS_8750]

I think it would be cool to implement a method similar to NGS.

Each time a monument is recovered and utilized for a RS, Corner Record, Parcel Map, Improvement Plans, etc., the surveyor files a little report with the County Surveyor that describes the condition of the monument, its purpose for use, elevation, coordinates, and other pertinent data.

[E_Page]

I think it's a great idea. Assuming that surveyors are providing the coordinates, monument descriptions, and any other pertinent data, then it's just a matter of data input for the GIS people. No professional judgment involved on their part at all.

For an LS utilizing the GIS to identify control locations, IMO one would be negligent if they relied solely on the metadata gleaned from the GIS and didn't go to the source data. It's reasonably common knowledge among surveyors and others that GIS data is less than (often much less than) totally reliable.

[hellsangle]

This is why I love this board . . . lots of brain fodder!
Have a great weekend!
Appreciatively yours,
Phil