OnX Property Boundaries ... Is this Surveying?

OnX is not very accurate, your neighbor is perfectly fine using it to find what he thinks is his corners. He can't be paid by anyone to "find" corners. The courts might sift through if he's liable when it is discovered that the "found" isn't really the corner.

I've seen OnX to be over 1000' in error at times. I got a relative large job to correct OnX which was using local GIS info and it was messy to say the least. Hunters were trespassing all over my clients property.

In a way it's a great app, keeps bringing in work for surveyors.

Their product description dances around the topic of actually by referencing the source of their boundaries as being based on maps and other information.

In essence, all of these types of apps consist of rubber sheeted nonsense and quasi related to WGS84.

I've never used it, but I assume it's like any other GIS where it could be pretty close or a long ways off.

As far as it being surveying I assume they have a disclaimer somewhere saying it's not a survey, but like I say I've never used it.

It's not surveying, they have a laundry list of disclaimers including:

"THE CONTENT MADE AVAILABLE THROUGH THE SERVICE DOES NOT CONSTITUTE A LEGAL SURVEY. OWNERSHIP OF LAND, WHETHER PUBLIC OR PRIVATE, MAY CHANGE AT ANY TIME. TO OBTAIN THE DEFINITIVE DESCRIPTION OF REAL PROPERTY, CONSULT THE DEED OR OTHER OFFICIAL RECORD MAINTAINED BY THE APPLICABLE GOVERNMENTAL AUTHORITY. DO NOT USE THE SERVICE FOR ANY PURPOSE REQUIRING PRECISE DIRECTION, DISTANCE, LOCATION OR CURRENT CONDITIONS."

OnX's accuracy is a direct function of land surveyors as the GIS departments rely on our plats and deed descriptions. PLSs that provide a precise means for the GIS or Tax Administration departments to anchor their client's parcels to State Plane, will find the resulting GIS boundaries a better reflection of the truth.

Some of our survey software manufacturers could benefit from mimicking some of OnX's key features. The hybrid topo/aerial map is great. Being able to use a two finger screen press to get an rough distance between areas on the map would also be a welcome addition to surveying software.

I've got to dispute the idea that the GIS is a reflection of the surveying community's work. I've been trying to fix the local and surrounding area GIS for almost 40 years. Had they hired my firm in 1986 to build the first set of parcel lines it might have had a better result. But, they went with a firm that told the county they could finish it in 6 weeks. LOL!!

They got what they deserved.

38 years later and it's still a mess, despite all the corner records, ROS's, Subdivisions, ect I've filed for the GIS's easy inclusion, it's still a mess. We even gave them state plane maps for large portions of the city, this was for SID projects throughout the city, it was all laid out and put into the city parcel map, Later, they hired an outside GIS consultant and it all disappeared (they used some online maps). Even our utility locations got removed and they sent out backpack GISers to locate the utilities we already gave them. Guess how that turned out.

I'm quite confident in saying if the GIS is wrong for parcel line location don't look at me. With all the helpful data I've given them it's all on them. Short of donating hundreds maybe thousands of hours of my time to actually correcting it, I've done my part.

I can confidently retire and say don't look at me when the question of why GIS is so bad comes up.

Hey MightyMoe,
I totally agree. I live in an area in Coastal NC that has a fairly good GIS, IF you know what areas to trust and the areas where your work will be the one that they correct the county data by. I usually use the GIS parcel data as a coarse map to put me on target to find corners and they've been anywhere from 6" out to an 80' delta. I think the issues is with "purpose". My understanding is that the purpose of county GIS parcel data has historically NOT been to accurately map the location of property lines, but rather to have a map that can geographically track Tax Data.... and annually remind us that, although we live free in the United States Of America, we really can't own anything. (And if you don't agree with that statement, don't pay taxes on the property that you "own" and the government will remind you of who really owns it)
***Apologies for the soapbox rabbit trail ***
In short, they're using GIS information in a way it was not originally intended, but now they are adjusting and reverse engineering it to try and make it work.

I'm not a huge critic of GIS by any means. Our local one has cleaned up much of the issues that plagued it for years. It's a good research tool for the beginning of title research. It still has issues there, but as long as you're aware you can mitigate that. But as you say it's more for tax and service purposes, it was never intended to be a precise boundary location resource. Early on they had my neighbor across the street being the owner of my parcel, plus four others nearby. Funny thing is that my tax bill never went to him.

Now all that has been cleaned up, so that's the important stuff with GIS the property lines are there for addressing and service people like police and fire getting to the correct house.

One local county fades away the property lines if you zoom in with the Ortho on. If you turn the Ortho off the property lines reemerge, that should be standard practice all across the country.

Again, I agree with you MightyMoe. Also, my county's GIS has this disclaimer that you have to "accept" to use the online mapping.

Disclaimer: The information in this web site represents current data from a working file which is updated continuously. Information is believed reliable, but its accuracy cannot be guaranteed. No warranty, expressed or implied, is provided for the data herein, or its use. Digital cadastral data are a representation of recorded plats and surveys for use within the Geographic Information System for purposes of data access and analysis. These and other digital data do not replace or modify land surveys, deeds, and/or other legal instruments defining land ownership or use.

This is good because it's basically the county everyone to "get a survey" before doing anything with their land.

I love the property lines disappearing on the zoom in. That would eliminate so many misunderstood conclusions. Just don't give them the opportunity to make a bad conclusion.

I haven't worked in that county for almost 10 years now. I don't know if they still do that, but it was brilliant.

I think this highlights the difference between establishing or retracing boundaries as a land surveyor, and using boundaries as a landowner, hunter, fisher, hiker, etc. Using boundaries is not land surveying and is not regulated, except by charging someone with trespassing if they get it wrong. When I see surveyors who drive monuments underground to prevent the neighbor from finding and moving them, or who will only give out paper maps, not digital ones, I wonder, did they ever consider that someone might want to use the boundary?

How about this: if a landowner or his/her predecessor in conceals a boundary by allowing a land surveyor engaged by him/her to conceal a boundary by driving the monuments underground, or failing to file a digital survey when means exist to do so, or by similar means, such concealment shall be a defense to any charge of trespassing?

Ashton,

I think that's one of the big sales pitches for software and apps like OnX. To make sure you're not crossing boundaries. This sounds good in theory. However we have 2 major problems. Are the data sources (Boundaries) accurate, and how accurate is the recreational GPS being used?

How about this: if a landowner or his/her predecessor in conceals a boundary by allowing a land surveyor engaged by him/her to conceal a boundary by driving the monuments underground, or failing to file a digital survey when means exist to do so, or by similar means, such concealment shall be a defense to any charge of trespassing?

I think you're making the assumption that a landowner can have someone charged with trespassing without giving the person the chance to leave the property. Is that how trespassing laws generally work? I honestly don't know the minutia of them.

I've always been under the impression you have to at least give the person a chance to leave.

That makes me wonder if there's any obligation for the landowner to prove they know where the line is-- like showing the trespasser the pins? Or is their testimony simply good enough?

In preparation for testimony in trespass cases I have confirmed with OnX that their maps, at least in my area (Mesa County, Colorado), are imported directly from the County GIS Assessor's maps. I was told that being a popular hunting region the maps of this area were updated 2 or 3 times a year. That may be so, but I am aware of areas that are well out of date regarding ownership and boundary lines.

My involvement has been related to the Colorado Parks and Wildlife officers issuing trespass tickets based on the OnX application, primarily along the rivers to waterfowl hunters. A review of the maps, OnX and GIS, reveals large areas without identified ownership along the rivers and canals. These are interpreted by some as "no mans land," leading to seasonal disputes. The gaps result from poorly written deeds, misunderstanding of riparian boundaries in Colorado and other factors, but they do not bother the Assessor as taxes for lands under waters are normally abated anyway. The GIS was built and is maintained to track properties for tax purposes! Occasionally, it is updated based on actual survey data, particularly when new lots are created. Otherwise it is mostly rubber sheeted from scans of historic assessor maps, which were not necessarily to scale. Even when an inaccuracy is discovered it is not an easy thing to correct. Unlike the occasional surveyor who is not bothered by overlapping descriptions, the assessor is very carefull to not assess taxes to multiple parties on the same piece of land. To correct the map for a single parcel may actually require revising the map for an entire section.

That rant over, I am a dedicated user of OnX for recreational activities.