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Any surveyors? A question....

Someone laid this down about 50 feet from my property line earlier this week. It’s 6’ x 6’ and 1’ wide. I’ve also seen these while out hunting and hiking. I’m sure there’s a simple explanation. Can anyone explain the use?

I'm not sure, but it may be a marker for aerial photos.

I'm not a surveyor, but am an engineer and use survey data obtained from aerial LiDar surveys flown by airplane, helicopter and drones. I wonder if those are known coordinates that are used to calibrate the data obtained? I always wondered how they do that?

Aerial marker for sure.

Aerial marker for lidar or photography...100%

Okay, got it. How does it work and what’s the purpose? Are there others laid down in the area? This one seems randomly placed for sure. There’s no corner marker close by, it’s not on a property corner but it is close to where the slope of the steep 900 foot tall hill begins.

I am sure there are others around. They will put these down and use regular robots or GPS units to set northing and easting on these points. They then fly over and use the flyover data in combination with the ground data. It could be used for aerial photos or lidar which is basically just ground elevations.

Not a licensed surveyor but a civil engineer. Have laid out a number of grids for aerial flight mapping.

That x is a target for aerial photography that is used to develop topo mapping. There will be a grid of points that is surveyed in off of standard survey benchmarks (State Plane or other standard) for latitude, longitude and elevation.

The plane will fly the grid at a specific altitude and on a pattern to get aerial photos from different angles that will use the ground grid to type into the overall standard grid.

Lots of pretty close answers, but to the point. It's a ground control marker used in aerial Photogrammetry. There will be a series of these positioned around the target area with survey grade receivers to sub-centimeter accuracy. The area will then be flown with a Cesna with a high end aerial camera along with onboard GPS or a drone (more common these days and cheaper). The overlapping photos, from the plane or drone along with the ground control will provide a number of deliverables. A georeferenced photo, a point cloud that will give you millions of points anywhere in the target area, and a surface model of the target area. In short, once flown, any and all features in the target area can be accurately mapped to centimeter level i.e road intersections, buildings, you name it.

I cut my teeth on this. Have flown drones in the Andes to Sub-Saharan deserts of Africa. Crazy cool technology that has been around for a looooooong time. I used to position panels for the DOD back in the day when everyone was our enemy. Anyways, sounds like a large scale construction project is underway and they're doing a preliminary survey.

Thanks Cazador! If you saw where I live and where the marker is it’s hard to believe there’s anything that’s going to happen in close proximity to this particular marker but as you stated it’s likely one of many. This one is right next to three private lots which are right next to very steep dessert hills that are 600’ and 900’ higher than the marker. Much of the land is BLM but some is private. That said there is land within close proximity, both BLM and private, that could be built on and the BLM has stated they might sell off some of the Federal land while the private is a massive parcel, most not useful, that’s owned by a land development company out of CA. I supposed that company could be working a large scale development project along with a land swap with BLM.

Damn! Caz with THE answer of all time! Learned something today.

I still know he despises trail cameras. :)

Tiltz,

The target area normally isn't small. It could be square mile ( very small) or hundreds of miles (large) that's why it's being flown vs a traditional land survey. In areas with a lot of difference in elevation, you need to place a lot of panels to account for it in order to get accurate vertical results. Also keep in mind, the data obtained from the flights is used in all sorts of ways, I didn't mean to sound like they're putting a highway corridor through your back yard. Many countries use the data for "Tax Purposes" as they have a complete overview of the property, and what's on it. Square footage, assets, you name it.

@ Embry, believe it or not, at one time I was thinking about providing aerial photos on properties where guys WT hunt. These aerials would be super high resolution, and would give a guy a true "Picture" of what the property looks like at any time of year. It would make google earth look like a 1960's Polaroid photo but then the Trail Cam side of me kicked in (just kidding).

Caz,

Thanks for the information! I’m asking more out of curiosity than anything since I’ve seen these markers all over NV throughout my lifetime. I’ve always assumed they were used for some sort of aerial survey but never really knew how that process worked and the purpose so now we all know!

There is also traditional ground surveying going on a 1/4 mile away and someone just dumped about 100 yards of backfill sand in the same area yesterday so something is definitely going on. We’re right on the edge of town with some of the only undeveloped land in close proximity to Reno so it’s inevitable that something’s going to happen at some point. Best case, the feral horses will get rounded up.

I'm a little late to the show on this one but I am a licensed land surveyor and a retired County Surveyor. Cazador and Treeline pretty much nailed it but just to simplify the answer a little. A surveyor will use traditional methods (usually GPS) to survey and determine the exact horizontal and vertical position (i.e. XYZ coordinates) of the center of every target. Since they then know the exact surveyed position of every target and the same targets are visible on the aerial images they use the targets to adjust the imagery to match the surveyed targets on the ground. They are known as ground control and without them the final aerial photography product would not be as precise as it needs to be.

Just happen to be creating point clouds and orthomosaics right now from a drone mission I just flew yesterday at the mine I work at. Definitely an aerial photogrammetry target. Really cool technology. As Caz said been around for a long time using large aircraft, really taken off with the upswing in drone technology. Used to do most of our surveying on site using lidar scanners and GPS surveys, we use drones a lot more now. Even got to fly drones with lidar scanners in our underground mine last year to map out drifts and stopes. You get some pretty amazing 3D models, just takes a bit of a learning curve to not fly one into a rib or chunk of rock!

“A surveyor will use traditional methods (usually GPS)...”

Actually, I think traditional survey methods would involve a staff compass and a chain!

Just yanking’ yours :-)

Pretty cool how varied the backgrounds are, of guys on Bowsite! This is but just one example!

I always find it interesting, as t-roy says, when someone like Mike gives us his background as he did above. I find that there are a lot of knowledgeable people on here regarding bowhunting as well as other related subjects. Some are very accomplished persons with interesting backgrounds as Mike's above. Along the way I've done some surveying myself back in the "Day" so his was especially interesting to me. Also, I know from threads on here that he is an avid successful elk hunter which I can appreciate. What Bullhunter says is very interesting also.

nowheels, it's funny that when I wrote that about GPS being "traditional" surveying methods I actually cringed a little myself. What I meant was ground surveying methods vs. aerial methods. I know you're just yanking my chain but I totally agree that I didn't use proper terminology and a staff compass and chain are true traditional surveying equipment.

I did a lot of surveying with theodolite, EDM and chain (steel tape) and plumb bob before survey grade GPS came along. I lived through the development of modern day GPS surveying and saw total stations replace theodolite and EDM and robotic total stations turn 2 and 3 man crews into 1 man crews.

The county I worked for did a new aerial photography flight every 3 years or so and I have a lot of experience with placing and painting the targets and performing the ground control surveys.

t-roy, I agree there is a lot of knowledge and interesting backgrounds among the members on this site. It's pretty impressive.

badbull, I appreciate the kind words. Coincidentally I believe my experience with topographic maps and surveying (very similar to navigation) has a lot to do with my elk hunting success. I know some guys struggle with understanding topo maps but having worked with them for years and having actually drawn them they're second nature to me. When I look at a topo map I can visualize a 3D image which really helps decipher elk habitat.

Question for all you surveyors out there. My land was surveyed in the late 40's early 50's. Was a lot broken out of a 1880's homestead. All the land surrounding the original homestead is national forest.

What happens if it is resurveyed with modern methods and the original survey is off? What I would worry about is what if my house is now on forest service land?

Terry

Cheesehead Mike, I also worked on crews through the transit and chain era and moved up to having a distance meter that was carried in its separate case the attached to the top of the transit.

My father began surveying full time when he retired from DOT, and he upgraded to a Topcon GTS2B total station, but it didn’t have the data recorder. I worked on his crew for about a year until I graduated college. After using that TS for a few years he upgraded to a GTS3B with a data recorder so that was nice. He retired for good a few years after that, but before the survey grade gps was readily available. Remember when the gov’t kept the selective availability limited to about 20 feet? It’s amazing how far everything has advanced now.

Coyote65, you’ll very likely have different acreage than that 70+ yr old survey shows, maybe significantly different, especially if there is a lot of slope involved. You may think you’re “gaining” or “losing” acreage, but in reality, you still own what you’ve always owned, you will just have a much more accurate survey. If your house turns out to be encroaching on USFS, the surveyor would note it on the plat. If so, I would talk to a RE attorney to find out the best course of action.

Coyote, modern surveying methods don't or shouldn't change the boundary of your property. GPS does not "know" where you're property corners are. GPS is simply a tool in the surveyors tool box that enables the surveyor to make measurements more efficiently. The surveyor still has to do the proper records research and search for evidence in the field. Modern methods such as GPS are then used to locate/survey the field evidence. Then the surveyor analyzes the evidence and develops a conclusion regarding the location of the boundary and accepts existing corner markers or sets new property corners and marks lines. There are rules of evidence that apply to property boundaries. Found original monuments (corner markers) are at the top of the list in the rules of evidence.Typically if your property was surveyed years ago there should have been markers set at the property corners and those original markers would typically hold unless there was some type of major blunder when they were set. If a survey was performed there may also be a survey map on file in the County Surveyors office or other County office where land records are kept. Part of the modern Surveyors responsibility is to research, analyze and retrace old survey records as well as the ownership records (deeds, etc) for the property. Although it may happen occasionally, a surveyor should not ignore existing boundary evidence and just set new markers without proper analysis of existing evidence. Sorry for the long answer but it can get fairly complicated at times and that's why boundary surveyors need to be licensed.

Here is a photo of me prepping a drone flight at 15, 500 feet in Bolivia.

Pretty sad that the laws here in the US really put the brakes on "Drone Technology". It is insane what they are doing with them these days in places outside the US.

It may be true that the FAA drone laws seem overly restrictive in the US, but as an airplane pilot too I'm aware of a lot of airspace incursions by drones and near misses with aircraft even with the existing laws. Some aviation experts say that it's just a matter of time until a hobbyist's drone takes down a commercial airliner.

Thanks for the info on updated surveys. Not going to get one, the legal description is recorded at the county, and I know where the corners are. Still have the original galvanized pipe corners.

Thanks.

Terry

I get the FAA stuff, but really, you have a mine the size of Rhode Island (exaggeration) but not far off, and you can't fly a drone without all the BS government regulations? Always seemed a bit controlling to me. Also, you can fly a drone for non commercial use no issue but if you're a surveyor, or will be using it for commercial use, you have to get a tail number? I get it, but at the same time, it's overreach as with anything else.

Staying on topic, it's a wonderful technology with unlimited deliverables. Sadly, I'm out of it now as I don't have a place to fly.

Terry, if you have the original monuments you're good to go and no need for a new survey.

I hear you Cazador, the regs are very restrictive for commercial use. It appears the FAA erred on the side of extreme caution when developing the regs. I wonder if they'll loosen up over time. Before I retired we were looking into purchasing our own drone to use for County highway projects, etc so I looked into the regs and attended several seminars on drones and surveying. Also being a licensed pilot, getting my commercial drone certification would be fairly simple and I had some interest in possibly starting a drone surveying business after retirement but I decided I was too busy hunting and fishing to work any more.

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