gbarber
good;-)
linebender
You are so right about that. There is no reason for surveyors not to be interested in trying such a national database. The best option being to work on it locally.
That is essentially what is occurring in any area that has a recording law. The only difference being that someone else is using the surveyors data to inaccurately place the parcels.
Some areas around here are requiring new subdivision plats be submitted with the CADD file. The area development district uses the line work to update their mapping and provides that to the property valuation office. If it is not on state plane, they have a technician who goes out and locates a couple of corners to translate to state plane.
I work on this locally just for the benefit of me personally and my community. I provide data to the local property valuation office for them to correct and update their mapping. In my short time span, I will not make a huge dent in the inaccurate data, but my eventual hope is that my county will have some very well done mapping.
Even with a very accurate parcel layer, there will be a need for surveyors for surveying off new parcels as well as the usual actually showing the homeowner where their property is actually located on the ground. Just because it is on an accurate tax map does not mean that all citizens suddenly know how to interpret a map.
linebender
> You are so right about that. There is no reason for surveyors not to be interested in trying such a national database. The best option being to work on it locally.
Seems that you have thought about this. Could you read my post here with these questions. surveyorconnect.com/index.php?mode=thread&id=176248#p176504
linebender
I read your post. I agree with what you are saying. I still believe that surveyors should get behind populating the national parcel database and push to get it done correctly according to boundary law. If surveyors don't do this who else will? It's a ton of work, convincing the public of the value (of not having boundary disputes) the real problem is funding. If they want accurate maps easily available there is an up front cost. The GIS can handle the data just fine but collecting the data is going to cost. The cost is the legal aspect of doing the boundary surveying and convincing almost everyone that the deeds are not mathematically correct. Heck we fight this issue within our own ranks. The work has to be done on the ground by those competent in boundary law. There is a lot more here than just using our great technology (GIS and GPS with the math).
YUP, the GIS is screwed up but not because of the technology but because of the nature of and history of boundary establishment and the fact that deeds are rarely mathematically perfect and some are just sketches of a true boundary description. This is what the public needs to understand. Yes, we can have it but effort and expense is required to get it.
I've been following this thread and it seems to me that the original question has yet to be answered:
> When is a corner monument, not a corner monument?
Answer: When it is not called for in the deed. The surveyors here must believe that they have sufficient evidence that is called for in the deed to place the deed corners and ignore the pre-existing, but uncalled for, corner monuments.
We have the suggestion that the quarter section corner - presumably a monument that is called for in the deed - may be the product of a half baked restoration. A properly restored section monument has all the dignity that the original had, but can an found, undocumented, PK nail be considered a proper restoration? It may therefore be the source of the difference in the survey results. Any of us might choose to consider the corner monuments and deed calls better evidence of the location of the quarter section corner than the found PK nail. But the surveyors involved evidently both decided against that. I can only presume that they had their reasons.
The long existing monuments may become controlling if the called for monumentation is missing or in doubt, and they are certainly evidence of prescriptive rights. But we aren't just doing the "Schaut" here and accepting occupation lines where we find them. Mere presence of buried irons isn't enough to ripen prescriptive rights. People have to know about and act in reliance on them is some way. If the long existing monuments had been well known to one and all would there have been need for a survey?
Just my personal opinion:
1. Here in WA, all of our parcels are already Geo-referenced since the 1800's.
Then you are light years ahead of my area. Locally the parcel layer is based on black magic marker lines that were sketched onto the 1960 era aerial photographs based on best guesses using fence rows and mow lines (and local land owners coming in and saying this is where my property lays).
These same magic marker lines were digitized and are on the high tech GIS now.
Fortunately, the current property valuation folks have been working diligently on entering the actual boundary descriptions and fitting them as best as they can. They have made great improvement in the accuracy of the parcel owners and how the properties roughly line up.
Of course they are dealing with matters well beyond their expertise in the best manner they can. They are working with the same issues as we as surveyors face - deeds that don't mathematically close, poor descriptions with few calls, completely inaccurate data, adjoining properties with differing basis of bearings and incompatible lines. However, they do not have the authority, means, or knowledge of how to go out and resolve the matter with field work and records research.
There are areas in western Kentucky that instead of starting my research at the tax map, I do a drive through of the site and look for street addresses and ask neighbors who their neighbors are. There are areas that my local tax office can not even begin to place in their GIS because the deeds are so poorly written that they can not even roughly place them on the ground.
2. Boundary law doesn't seem to base boundaries on coordinates, they are based on relationships to monuments on and in the ground. (Our Geo-referenced system from the 1800's is tied to errorless monuments on the ground.)
I would never see this changing. However, there are many uses that a more accurate parcel layer could be put to beyond just a person trying to use it as a boundary resolution tool.
As mentioned above, there are many areas that the parcel layer is so poorly related that you have absolutely no clue how properties even relate to each other. Extending that poor data out, there can be less accuracy in voting districts, school district's, 911 locations, etc...
3. In my experience, when a city asks for a tie into NAD83/91(xxxx), what they end up really asking for is a tie into their own realization of NAD83/91 as it relates to their monuments. This is just how a moving earth works. Any coordinate that is not 4-D is not really Geo-referenced, and I think that might be a little extreme to work up for a corner for a parcel + house worth $300k.
I agree, but providing data on the local realization of a coordinate system seems to be a better option than just hanging it out there on a local system and letting a GIS tech twist it onto the edge of a gravel drive and distort the shape until it fits his idea of the parcel.
As long as the system works within itself, there is always the option of making a transformation in the future with enough checks to confirm accuracy to the new coordinate system. I would see that as the final bit of adjustment to get the 'national' parcel system tied together.
4. Are we going to change hundreds of years of law to hold math over monuments?
As you are already in a geo-referenced area, I would like your take on it. Has the better relation of your states parcel layer replaced the legal principles of surveying?
I can't imagine it would. The difference I see would be that (hopefully) the parcels would be getting better and better related as surveys are tied together. No different than what happens in your office when you might survey a parcel and then tie it to a later survey a couple of tracts to the north. You may be missing some of the data for the parcels in between, but you sure have a better idea of where to start looking when you get the call for the survey of the parcels in between what you have already done.
Would we eventually get to a point of relying on the coordinate? Possibly, but that would be a long long way down the road. Further, I would expect that the coordinate could still be rejected as the corner based on all of the principles we discuss and argue about on this board every day.
I would not expect that the national parcel layer would really make much difference to the usual land owner. They would still hire a surveyor because they would not have a clue of what they were looking at. Sure there would be some folks who would try to use the data to do their own surveying, but that happens already.
5. Where in the "National Land Parcel Data: A Vision for the Future" publication does it spell out how we are getting Joe Homeowner to pay for these costs?
That is an interesting question. If it is attempted in one big push, there sure would be a major cost with doing it. If it can be worked on a little at a time on the local level, it might take longer than impatient folks would wait for.
