DIY Land Survey

[Highbeam]

I got a chance to see just how expensive those fancy prisms were when some hoodlum stole my backsight!! Backsight being the tripod mounted prism on the other monument used to establish your location. The crooks actually released the prism from the tripod and made off with it. I'm sure the kids don't realize how expensive the fancy mirror is in their bedroom. Nomatter where you are when you look at the prism you always see your eye.

 

[HomeBrew2]

... some hoodlum stole my backsight!! ....

Ouch! Yeh, now that I'm going to have to tramp around the neighborhood tieing out corners, I figured a bike reflector tacked to a plumbed lath would be an expense I could tolerate should it get swiped or runned over.
Also nice to be able to tack up a dozen of em on trees, etc, take a dozen shots, grab a beer, repeat.

 

[dillo99]

On a related topic..........Here is a website that has satellite photos and topo views, along with a planimeter for calculating acreage / dimensions. The planimeter works pretty good once you mess with it.......


Google Planimeter

Try Google Earth Too! Requires a download but is very cool. I was able to take a scanned survey property map of my 27 acres and then fit it over satelite photos from Google Earth (you can make the map transparent). This allowed me to locate all the corners of my property quite easily. You can also add your own markers and use a ruler to take accurate measurements. It is pretty cool stuff.

Google Earth - Home

 

[HomeBrew2]

... This allowed me to locate all the corners of my property quite easily. ...

I am a fan of the accessability of land plats and other legal records and aerial photos via the internet, no matter the source. Google "anything" is worth what you pay for it.

I think we may have a slight disconnect between reality and "internet-based surveying" on this particular thread though.

The internet is a wonderful resource for information of all kinds. And many hits from a search provide real, usable info. Copying, pasting, rotating, scaling, is fun ... and has great visual benefit ... but virtually no merit in regards to a legal, court-substantiated boundary.

Just my take on reality as I know it ...

 

[Champy]

HomeBrew2 - "The internet is a wonderful resource for information of all kinds. And many hits from a search provide real, usable info. Copying, pasting, rotating, scaling, is fun ... and has great visual benefit ... but virtually no merit in regards to a legal, court-substantiated boundary"

I agree 100% regarding the legality of it. However I was using the online planimeter to estimate the boundary lines of properties for sale that we were considering splitting. Nobody wants to pay $3k for a legal survey just to determine where the north half of a odd shaped 60 acre farm really lies - then find out you really don't want it. I also used it to approximate acreage claims by realtors - and you'd be surprised how far off they were!

I "surveyed" the land we ended up buying via the online method, and kept coming up with 5 acres more than the realtor or the county accessor showed. Guess what - after the formal (legal) $urvey......we had 4.3 more acres! This process won't stand up in legal terms for deeds; etc.. but as a quick and easy means to estimate property lines; acreage; etc.... you can't beat it.

 

[HomeBrew2]

... you can't beat it....

I'm with ya man. When it works, it WORKS! And I am glad it worked for you Umm, also glad you had it surveyed but sorry it was so much $.

 

[zeuspaul]

**When it Works** and sometimes it does. But sometimes it is doesn't.

I used the property lines and aerial photos from Zillow.com along with the contours from Topozone.com to *point* me to my property lines. I was then able to find the actual property markers.

However I also have the legal description to verify that the online stuff is at least close to being correct. I looked at the online property lines for a couple of neighbors and some were right and some were totally wrong.

Zeuspaul

 

[HomeBrew2]

**When it Works** and sometimes it does. But sometimes it is doesn't....

This seems like an appropriate time to open the can-o-worms regarding internet "parcels" and such. (Uggg)

Unfortunately, rarely, does anyone notice, or have access to the metadata (specifications about the 'data') for the online parcel data. Most folks assume that because it comes out of a 'puter, it's dead nuts and gospel.
Obviously to some, this is the realm of GIS (geographic information systems). This may be a news flash to some, THERE ARE NO STANDARDS, LAWS, UNIFORMITY OR ANYTHING ELSE THAT QUANTIFIES THE ACCURACY/PRECISION OF THE BOUNDARIES DEPICTED in a real-world-coordinate representation.

Case study: I built and now maintain the GIS in a neighboring county. Unfortunately, the Board of Supervisors funded the data development but, did not fund any field surveying, in any context of the phrase, as a basis for the parcel layer. What we wound up doing was scanning all the Assessor's maps and squishing, squashing, streching and morphing everything to fit inside the individual "sections" (public land survey sections) as they are depicted on USGS quad sheets.

An educated guess as to the accuracy of our parcel data is +/- 20% in the worst case. Best case, 1%. (1%=A city lot with 60' frontage could measure 60.6' or 59.4'.) You do the math on the worst case for a large parcel.

So, my purpose in my little [professional] world is to strongly advertise our "parcel" data as being a really neat graphic index of the 130,000 or so parcels in the county ... with absolutely no realation to real world dimensions to any specific parcel of land.

No, I'm not the least bit happy with this state of affairs of data accuracy but am very aware of the astronomical amount of money it would to take to research, survey (even with GPS), calculate, adjust, and publish accurate parcel data for 4500 square miles of dirt in one of the poorest counties in Kalifornia. And, I'm sure there are jurisdictions a whole lot worse off than the county I work for ... but everybody's website looks cool

Reference: I have a Bachelor's in Land Surveying and Photogrammetry from Fresno State U, LSIT certificate, 15 years partychief/field engineer, 2 years Chief of Surveys, 11 years GIS.

Cheers!

 

[crocodile_jkg]

Hey guys:

I was wondering if you could do a quick survey or even a topo map of property using consumer gps units? Seems like it should be doiable?

James

 

[HomeBrew2]

Hey guys:
I was wondering if you could do a quick survey or even a topo map of property using consumer gps units? Seems like it should be doiable?
James

Here's my take on it: If you can walk your driveway, or other simple route, two or three times and get the same results, horizontally, you've got a good chance of making it happen. I couldn't get better than +/-50' among discrete "surveys". Be aware that horizontally, [consumer] GPS, is, or has the possibility of being, fairly accurate but, vertically it is pretty hard to get reliable results ... the satellite geometry is just wrong and usually results in poor solutions.