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Can any on tell me how to convert the measurements in a deed or plot survey in to GPS coordinates? I planed to have an actual surveyor do a proper survey but until I can get some one out I would like to have a rough guess.

If you look at page 2 you will see the measurements I'm looking to convert to GPS coordinates.
View attachment NCWV_27712.pdf
 

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I think the closest you could get is with google earth, and just trace out a rough path. It will be accurrate to 50 feet or so if you are careful, and know the natural landmarks
Surveyors don't make it easy to do what you are talking about.
I couldn't really make out the numbers on your scan, but somewhere on the survey there is an "origin". The 2nd point is a compass heading and a distance from the origin, then the 3rd point is a distance and compass heading from the second point. So every point is based on the point before it. Even the "origin" is based on a "monument" maybe a mile or 2 away. Not at all a user friendly system, but that was the only way to do it before GPS.
 

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I just recently tried to do what you are asking, using my "plot plan/survey" and convert to GPS. I bought the plot plan to my development, but there must be a larger map somewhere which shows a survey monument and actual longitude and latitude. My development map didn't have it, and I haven't had the chance to visit my county's record building to research it more.

As the 2nd post said, the numbers are bearings and distances from point to point. Surveyors would start at a corner of your property, usually marked by a stake or re-bar, and then move to the next location by the compass bearing and the distance. And repeat until finally ending back at the start.

If you know the GPS coordinates from one point, you can download some free programs that will convert bearing and distances into GPS lon/lat, so you can fill in the coordinates for each corner of your property. The "trick" is that you need to find out the GPS coordinates of at least ONE corner of your property. Sorry, but I don't have any quick way of finding that out other than taking a reading with my smart phone, Garmin, or Google earth. It's not the most accurate, but it will get you "in the ball park" of several feet.

I finally just located my re-bar stakes at the front of my property and measured (with a tape measure) to the rear, using my best guess for bearing and some natural features as possible property markers. By natural features, I mean things such as stone walls, old trees, etc. that were around when the property was subdivided. It was good enough for me to "estimate" the borders of my lot.

BTW, I did call a local surveying company, they estimated it would cost me in the neighborhood of $1500 to $2000 to have a lot survey. (I only own 1.5 acres). I was cheap and my estimate was good enough for what I needed.

Just my 2 cents, and good luck.
 

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As others mentioned, it's not all that easy, or everyone would be doing it. :lol:
And I WISH I could get mine done for $2000. Six or seven years ago the estimate I received was in the $3000-$4000 range. I can guess it would be quite a bit higher today.

The key really is that first monument, and a very accurate way to measure your bearing. The distances aren't difficult, just some time needed to convert odd units such as perches and rods into feet and yards.
 

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As others have said, it's not as easy as it should be. I have a Garmin hand held GPS and I find the coordinates change each time at a known point of reference. You need military or surveyor grade GPS, not consumer grade like I have.

Other things affecting the true length between two points are elevation changes and the curvature of the earth.

What I've done with our two properties is go to the county and get plat maps and input the data into AutoCAD, which I'm fortunate to have, and most of us don't.

There are also numerous measurement systems that surveyors and navigators use, which confuses the issue further.
 

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Here is a website that has a lot of calculators (and code) that I found a while back. There is a lot of information on the site, and I just used one of the many calculators. You just have to scroll down until you find the right one. Though it uses kilometers for distance, it works for shorter distances after you convert. There must be other similar sites too.

Calculate distance and bearing between two Latitude/Longitude points using Haversine formula in JavaScript

I used one of the calculators to find the GPS coordinates of the other corners of my land, after I got an average of the coordinates of the first corner. I used Google maps, garmin and a GPS app on my smartphone. In addition, my county has a "parcel access" pr "geo access" site that overlays property boundaries over a satellite image. It gives lot information, owner of record, property size, some latitude and longitude and much more. Search "parcel access dutchess" to see it for my area. Your county and state may have a similar site.

Surveying is an interesting field, it's interesting how they did it before GPS.

More of my 2 cents.
 

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You guys ever use google earth? It is fantastic job of measuring distances and plotting lines.
 

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Discussion Starter #8
I think the closest you could get is with google earth, and just trace out a rough path.
Google earth keeps crashing on my mac but I did find an awesome web site to do arial photo measurements in WV, for those who live in WV or those just interested you can find it here. There are multiple map layers to pick from.

I also have the deed that has the heading and distances so reading the writing on the old plot survey is not needed, I just did not want to post the deed to the web site not that someone couldn't figure it out and look it up anyway.

Here is a website that has a lot of calculators (and code) that I found a while back. There is a lot of information on the site, and I just used one of the many calculators. You just have to scroll down until you find the right one. Though it uses kilometers for distance, it works for shorter distances after you convert. There must be other similar sites too.

Calculate distance and bearing between two Latitude/Longitude points using Haversine formula in JavaScript

I used one of the calculators to find the GPS coordinates of the other corners of my land, after I got an average of the coordinates of the first corner. I used Google maps, garmin and a GPS app on my smartphone. In addition, my county has a "parcel access" pr "geo access" site that overlays property boundaries over a satellite image. It gives lot information, owner of record, property size, some latitude and longitude and much more. Search "parcel access dutchess" to see it for my area. Your county and state may have a similar site.

Surveying is an interesting field, it's interesting how they did it before GPS.

More of my 2 cents.
Tomfive- you have really gotten me going in the right direction, thank you. Last night I figured out what I thought was a close lat and Long for my first pin and was able to use the measurements and heading and get all the way around lot line. I mathematically ended up where I started so their formula is good.

The main reason I'm trying to find the lot lines quick is my neighbor is dumping in the woods behind my house and I want to make sure it is not on my land. If he is close to my rough guess then we will have to resolve the issue but I don't wait the 2 months for an official survey. I have also had a couple of what I call "Dirty Hippies" wondering behind my house looking for ginseng. Not that I want to deny someone a way to make an income but I don't like people walking through my property with out my permission. So I would like to put up no trespassing signs.
 

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Tomfive- you have really gotten me going in the right direction, thank you...
felixm22, you're quite welcome. :hi:

My wife and I had a fun time learning amateur surveying and marking our property, at least estimating our outer limits. We did it for a slightly different reason, my good neighbor got "convinced" by a tree service to take down about a dozen 25 yr old spruce trees along our property line. The trees were planted by the previous/previous owners, and were basically on their property by a couple of feet. They got a little scragley(sp) but they could have been pruned. It actually turned out that a few of those trees were on out property. Oh well, they're gone. Don't get me wrong, we have great neighbors.

So now that the privacy tree line was down, my wife and I decided to put some drainage lines in and start planting new trees and shrubs to give us some more privacy and fill in some low spots that collect water. We just wanted to make sure we were on our side of the property line. We found a lot on the internet, and I called a couple of surveying companies and got more information. So we marked our property with some stakes and string and the digging continues.

Good luck with your neighbors.

BTW, today, surveyors use differential GPS, much more accurate that our conventional units, and much more expensive. But that is another story.
 

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Discussion Starter #12
Also consider if the bearings given are true or magnetic. Most are based off true north.
I would have to double check to be sure but I'm sure that the website that Tomfive posted does go off true north. In digging I also came up with the formulas on how to convert surveyors directions into compass directions it is posted below:

For all quadrants, to convert quadrantal angle to true bearing:

NE: Use angle as is
SE: Subtract angle from 180°
SW: Add angle to 180°
NW: Subtract angle from 360°​

Tomorrow I going to take out the GPS and see if I can get an idea of where stuff is and maybe I'll catch the dirty hippies.
 

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You guys got me interested in my property lines and I have a few questions for you.

I dug out my deed and of course it is in this format:

S 80 degrees W for 7 perches

It was easy enough to figure out the heading, and a perch is just 16.5'.

Now for the questions. I would guess that since the survey on my deed was performed 100 years ago, it was using a magnetic compass. Would this mean if I wanted to go out and borrow a transit/theodolite (a friend used to have one) and make an amateur survey of my property that I would also just use a magnetic compass? If I use a GPS system, is GPS magnetic, or true north?

And now for the fun part, since the Earth's magnetic field changes over time, it introduces an error into the magnetic bearings over time referred to as "declination" in the online research I have been doing. The declination changes over time. For my location in 1900 the declination was -7° 41' 24". At present my declination is -12° 21' 41". Would this mean I need to add 4° 40' 17" to my magnetic bearing when using a magnetic compass and subtract 12° 21' 41" from my bearing when referring to true north?

And taking into account the terrain around my place, as well as tracking down deeds and property records, I can see why the surveyor said it would be a multi-thousand dollar job. :laugh:
 

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You guys got me interested in my property lines and I have a few questions for you.

I dug out my deed and of course it is in this format:

S 80 degrees W for 7 perches

It was easy enough to figure out the heading, and a perch is just 16.5'.

Now for the questions. I would guess that since the survey on my deed was performed 100 years ago, it was using a magnetic compass. Would this mean if I wanted to go out and borrow a transit/theodolite (a friend used to have one) and make an amateur survey of my property that I would also just use a magnetic compass? If I use a GPS system, is GPS magnetic, or true north?

And now for the fun part, since the Earth's magnetic field changes over time, it introduces an error into the magnetic bearings over time referred to as "declination" in the online research I have been doing. The declination changes over time. For my location in 1900 the declination was -7° 41' 24". At present my declination is -12° 21' 41". Would this mean I need to add 4° 40' 17" to my magnetic bearing when using a magnetic compass and subtract 12° 21' 41" from my bearing when referring to true north?

And taking into account the terrain around my place, as well as tracking down deeds and property records, I can see why the surveyor said it would be a multi-thousand dollar job. :laugh:
Wow Andy those are some good questions. As you said the magnetic field around the earth varies so I think GPS uses true north. The one web page that I was using to plop in the first GPS coordinate just spits out the next GPS coordinate. I took the new coordinate and put it into Google maps to see where it was. If it looked close I knew I was going in the right direction.

I would think that your survey would have used true north, but you may want to look at a plat map or county records. You could try the same thing with google maps, if you have long property lines I would think 12 degree would be easy to see.


Sent from my iPhone
 

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That is my problem. I believe google maps uses true north. To get from one point to the next, I have to use the bearings from my deed, which I believe are 100-year-old magnetic north. There are no real markers around my property (that I have found) since I believe it was last surveyed 100 years ago. There used to be a monument at one corner where the previous owner sold a small parcel to his brother, but the previous owner was an ass and one day dug it up. Oh, I know where the monument is, it is over a hill behind my house. Of course that is about 150 yards from where it USED to be. :thumbsdown:

What I'd like to do is an amateur survey of my lot with a transit. I believe just following the bearings in the deed will allow me to make a complete circuit ending up where I begin, but I'm just wondering if it would be 4° and a few minutes skewed from where it really is. That wouldn't be a big deal, but the property is oddly shaped and 1000' deep, and 4° starts adding up at that point.

Google maps isn't too bad, but I really need the satellite view to be of any help, and there is extensive tree cover so I really can't tell what is on the ground to use as a reference.

There are other oddities on my lot, such as the deed referring to the original road in front of my house which was moved about 25' south 60 years ago. A "pin in the center of the road" 100 years ago, is not the same pin that may be in the center of the existing road.
 

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That is my problem. I believe google maps uses true north. To get from one point to the next, I have to use the bearings from my deed, which I believe are 100-year-old magnetic north. There are no real markers around my property (that I have found) since I believe it was last surveyed 100 years ago. There used to be a monument at one corner where the previous owner sold a small parcel to his brother, but the previous owner was an ass and one day dug it up. Oh, I know where the monument is, it is over a hill behind my house. Of course that is about 150 yards from where it USED to be. :thumbsdown:

What I'd like to do is an amateur survey of my lot with a transit. I believe just following the bearings in the deed will allow me to make a complete circuit ending up where I begin, but I'm just wondering if it would be 4° and a few minutes skewed from where it really is. That wouldn't be a big deal, but the property is oddly shaped and 1000' deep, and 4° starts adding up at that point.

Google maps isn't too bad, but I really need the satellite view to be of any help, and there is extensive tree cover so I really can't tell what is on the ground to use as a reference.

There are other oddities on my lot, such as the deed referring to the original road in front of my house which was moved about 25' south 60 years ago. A "pin in the center of the road" 100 years ago, is not the same pin that may be in the center of the existing road.
I'm sure not an expert, but My wife and I, and her siblings embarked in an "epic" surveying adventure this last December. We surveyed and split many hundreds of acres into smaller pieces of hundreds of acres. The terrain was varied and rugged, and included roads, streams, woods, right of ways, tillable fields, 6 different building sites, and pastures. The bill was over 20,000.00.
After going through all of that, and asking the "man" allot of questions, I do have a few "fun facts" of things that I learned that may interest you.

1) A surveyor is definately a skilled trade:laugh: The math and geometry that goes into the process is unbelievable. Some might say "but now it's all GPS" but, they still have to locate the monments and origin stakes, further in heavy tree cover and certain terrain, GPS doesn't work.
2) a legal survey is accurate to 1/100th of a foot
3) when an existing fence line of an "old survey" is found to be inaccurate, usually, in court, a modern accurate survey trumps the old one.
4) The surveyor corrects for the magnetic variances, and the curvature of the earth...still small errors creep in, and there are areas of "no mans lands" that all have to be worked out.
5) google earth is pretty damn good at getting close
6) the surveyor has to work closely with the county and you attorney to pull everything together at the end...all of the legal descriptions, easments, right of ways, DNR liens, etc.

So I guess you can get close yourself, I think, but you probably already know pretty close where your property line already is, and I don't think you could get any closer with a compass and GPS
Any "squabbles" one may have with the neighbors or "dirty hippies" would need to be resolved with a legal survey anyway.

But it would be fun to play around with a transit, and see how close you could get to a "known good survey"
 

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Andy, you have a lot of good questions. Sorry I can't help there. But regarding the missing/moved monument, if there is an adjacent property that has been surveyed more recently than your property, maybe they had stakes put in, or monuments on their property that you can use for reference. When I was asking for survey quotes, I mentioned that I didn't know if my re-bar markers that I saw 25 years ago were still there (neighbor whacked it with his lawnmower one day and soon after that it was gone). The surveyor said no problem, they look for markers on nearby properties and measure from there.

Something more complicated is the reference to the national geodetic survey markers. These are "permanent" markers with known latitude and longitude scattered throughout the US. There may be one near your property, and some larger survey maps "may" show some reference to one of these permanent markers. I'm not sure if these markers were available when your 100 year old survey was made, and it'll be a lot of work working this way. We thought it may be fun trying to find a few of these geodetic markers in our area.

One other thought, if you're just trying to get a better idea of your property lines, and not trying to build/modify the land, then just "amateur survey" your land, mark it and let someone else dispute it. That's basically what I did around our property. :laugh:

Just my 2 cents. Good Luck.
 

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Thanks guys. I know a real legal survey is the only one that counts, but I think it would be neat to try and make a best guess at the boundaries. One reason I would like to do it is because the neighbor had a survey performed a few years ago, and the line where our two properties meet seemed a little off to me. From what I could tell, they used a corner point in the middle of the new road, versus the 100-year-old road. The area is wooded, and neither of us are doing anything there, and there is a path we both use that runs right along the property line. It isn't like I'm worried about any construction or fences or anything, but I would like to know where that one property line is. If my amateur attempt shows a large difference between her survey, I would keep it for future reference in case either of us DOES decide to ever do anything along this path. At that point I would have to foot the bill for a proper survey.

I have to do some research to see if the county or township has a map of permanent monuments in the area.

Knowing what I know now, if I ever purchased a rural property again (or knew someone about to), I would make the purchase contingent upon a proper survey being performed and the boundaries clearly marked.
 
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