General survey question on possibility of referencing using plat map

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My wife and I just bought our first house and a bit of land. There’s a constant stream flowing through one corner, and the previous owner had built a dam and a pond. A few years ago, during a flood, the water overwhelmed the overflow pipe, eroded the dam, and blew out a 6-foot-thick section at the center.

Eventually, I’d like to topo the dam and surrounding area to determine how many cubic yards would need to be imported for repairs.
It would also be helpful to be able to find property lines/ corners (not for legal or building purposes, I would hire licensed surveyor) I have rover and data collector, local base with radio corrections and pay for CenterPoint RTX.

This type of survey or layout is different from anything I’ve done before, usually have a cad, vector PDF, controls set by surveyor, or can ask for easting and northings.

Trimble Business Center would be helpful for answering questions like: If I want a pond of a certain size, how much further would my dam embankment tie-in points need to extend? How many truckloads of material would I need to import, etc.? Right now, I have a lot of priorities after buying the house, so I wouldn’t pay for control points.

We own lots 6 and 7. I’m curious, using the given plat map, which includes extensive distance and bearing data, if I could recreate the property lines in Trimble Business Center (within 6 inches or so). And then horizontally refence the lines.

Is it possible to determine a grid coordinate point using Bearing-Bearing Intersection or Bearing-Distance Intersection alone? I understand that a bearing is a highly precise direction, but if I’m picturing it correctly, on a grid, without any coordinate to tie any one line or point to, you could have an infinite number of sets of two lines with identical bearing and distance, and their intersection points could result in an infinite number of coordinates.

I think I would need just one set of coordinates, it could be a start, end, corner, intersection, or a point-on-line (POL) with a known distance to or from that point?

Looking at this very blurry copy of the plat map (that probably was a hidden 1000$ fee in closing) do you see anything that could tie any lines to the grid?

Are there any online or public record resources that could provide the coordinates of any “found iron” markers called out on the plat? Or would best bet be to find a online listed control point in the local area and do a single point datum shift using RTX?

182 Graham Creek Rd Plat Map.pdf (116.3 KB)

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If I was doing it, I would COGO the property line geometry over in Civil 3D without worrying about where it was in the world, fire up a new TBC project in your favorite State Plane coordinate system, go find the monuments and shoot them on the State Plane project, then bring in the property linework and best-fit it to the monuments as best you can. The monuments trump the mathematical coordinate geometry regardless where surveying property corners is concerned, but if you can find two monuments and line up the rest of the linework, it may help you find the other monuments or make assumptions about the other property lines.

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I would recommend a similar workflow.

If you are using Siteworks, once you have 2 points recorded, you can georeference the image to make it easier to find the rest of the data you are looking for.

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I wish that was the case on the monument trumping the Math. I had my house surveyed and they found two in the front. Within the same month the house next door line was surveyed and guess what. The new surveyors decided to add new rebar for the corner lines. which my rebar was visible.
Use you GPS with your state plane zone coords thats after you find the corners. More likely you wont find all of them, so its going to be find some and either turn angles or let TBC help out. There are times you can draw lines in Google Earth and bring them into TBC to work off, if you have some reference object to go off. Then you would bring that in and export back to Google earth to see how much is needed to be shift to fit for layout. A little more work this way from the office.

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Jonathan,

Since you have RTX, you can configure the coordinate system to align with the NAD83 system specific to your region. If you’re unsure of the correct system, you can use this site to identify it. Once determined, set up the coordinate system in Siteworks accordingly. The key step is to ensure the transformation is set from ITRF to NAD83, followed by selecting the appropriate zone. This process ensures accurate translation into true State Plane coordinates. Once configured, you can import the .cal file into Trimble Business Center (TBC) for seamless integration. Any points you shot in the field will now be State Plane. You can then rotate your PDF into the site by the points that you find in the field.

To find your zone you can use this site. https://www.stateplane.org/

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