Survey Markers

[+-Sapper-]

Ok I don’t know if I am in the right forum, but I was hoping you could help. My organization has me trying to find our property markers that where installed around 1940. They are mostly brass cap things. I can post a picture if you would like. I was given a long list of coordinates help me find them, The only problem is the coordinates I have are in What looks like UTM. so just assumed I could use one of those free online translators, like http://jeeep.com/details/coord/. only when I do that it puts me about 7 degrees above the equator, and I’m in Oregon...... I know I'm in zone 10, so the only other thing I can figure is that northing/easting zeros aren’t the normal ones.

 

help me, im clueless. I’m going to be out in the woods with a metal detector forever.

 

thanks

-sapper-

[stvanme]

If you posted a listing of the coordinates and some idea of where in Oregon the property is located it would be easier to help you.

[holograph]

Ok I don’t know if I am in the right forum, but I was hoping you could help. My organization has me trying to find our property markers that where installed around 1940. They are mostly brass cap things. I can post a picture if you would like. I was given a long list of coordinates help me find them, The only problem is the coordinates I have are in What looks like UTM. so just assumed I could use one of those free online translators, like http://jeeep.com/details/coord/. only when I do that it puts me about 7 degrees above the equator, and I’m in Oregon...... I know I'm in zone 10, so the only other thing I can figure is that northing/easting zeros aren’t the normal ones.

 

More than likely your property is described in state plane coordinates. Try using the conversion at http://www.ngs.noaa.gov/cgi-bin/spc_getgp.prl and see what you get.

 

You will first have to find your zone number by using the related tool at http://www.ngs.noaa.gov/cgi-bin/spc_zones.prl

[Z15]

Maybe you have the coords swtiched. x for y

 

Your GPS rec should convert them for you.

Set your GPS'r to UTM, enter the UTM coords and then switch to NAD83 Datum and see if it will convert to lat and lon. I don't know if all GPS'r have these features but the more expensive ones do.

Edited May 25, 2006 by Z15

[Photobuff]

I find this whole state plane thing very confusing. You might also find this link useful:

 

http://gpsinformation.net/state-plane-mag.html

[+-Sapper-]

Maybe you have the coords swtiched. x for y

 

Your GPS rec should convert them for you.

Set your GPS'r to UTM, enter the UTM coords and then switch to NAD83 Datum and see if it will convert to lat and lon. I don't know if all GPS'r have these features but the more expensive ones do.

 

ok ill give this a shot. We have a bunch of differnt GPS at work, ones bound to have this.

 

thanks

[+-Sapper-]

If you posted a listing of the coordinates and some idea of where in Oregon the property is located it would be easier to help you.

 

all rigth thanks. Ill bring some coordinates, and my best guess as to where they belong to home from work tonight

[+supertbone]

When I used to work on a survey crew I would often find them buried and would have to use a metal detector and shovel to find them when I was in the general area. Occasionally they were missing as markers are attached to semi-perminant structures like wood posts. Those thing rot.

[+Kewaneh & Shark]

Assuming your coordinates are UTM coordinates, the easiest thing to do would be to set your GPSr to UTM as it's primary units and then go hunting. If the units are State Plane (I believe Oregon has 2 State Plans zones which run east/west), the only reliable conversion program you can use would be the NGS conversion programs linked by Holograph above.

 

In the UTM system, the zones run in a north/south direction and the northing units are larger than the easting units. for example, the UTM coordinates for Salem, Oregon are UTM 10 497231E 4976608N. (The northing is nearly 5 million, but the easting is less than half a million.) If you don't know from your coordinate list which numbers are the northings and which are the eastings, change the primary units in the GPSr and go outside and let it show you where you are. The numbers it shows and the numbers on the coordinate list should be similar.

 

- Kewaneh

[stvanme]

If you posted a listing of the coordinates and some idea of where in Oregon the property is located it would be easier to help you.

 

all rigth thanks. Ill bring some coordinates, and my best guess as to where they belong to home from work tonight

 

Just what part of Oregon is all that is needed, such as what town/city is close by.

You also might have to consider that these are local coordinates. Land surveyors in the past often establish their own system used just for surveying a particular parecl or job. They would makeup the X/Y's and assign them to a location. Such as X=5000.00, Y=10000 @ SW property corner. They would be related to no coordinate system in the real world, just an aid in the surveying of that particular parcel. For this reason you don't often see these published/distributed, but I have on some occasions.

With the advent of GPS and state laws requiring real world coordinates you don't see this much anymore, but I still see it done for "quick and dirty" jobs.

[+Kewaneh & Shark]

...You also might have to consider that these are local coordinates. Land surveyors in the past often establish their own system used just for surveying a particular parecl or job. They would makeup the X/Y's and assign them to a location. Such as X=5000.00, Y=10000 @ SW property corner. They would be related to no coordinate system in the real world, just an aid in the surveying of that particular parcel. For this reason you don't often see these published/distributed, but I have on some occasions...

 

Your coordinates could very well be on a local & assumed system. It is a very common practice, at the beginnings of a project, to assume a coordinate system, and at times, an elevation (datum). Through the course of a project, if reference to an established coordinate system or datum is required, the proper calculations can be made to transform the existing data. If there is no such requirement, and most times there is not, the local system is maintained throughout the course of the project. This coordinate system is for internal, calculative purposes only, and (very) rarely published or shown on a map.

 

...With the advent of GPS and state laws requiring real world coordinates you don't see this much anymore, but I still see it done for "quick and dirty" jobs.

 

State laws govern accuracy standards, mapping standards, and State Plane coordinate system use standards, not coordinates systems to be used by surveyors on a day to day basis. State law can require that if a coordinate system is to be published on a map, that it meet a certain criteria, or that it be in a particular system for a particular type of map. The advent of GPS has had nothing to do with this. State Plane coordinate systems, their use, and the laws that govern them, have been around for years. What GPS has done is made the use of such systems easier, but assumed coordinates systems are still used on a daily basis because of their simplicity and ease of use.

 

- Kewaneh

[stvanme]

...With the advent of GPS and state laws requiring real world coordinates you don't see this much anymore, but I still see it done for "quick and dirty" jobs.

 

State laws govern accuracy standards, mapping standards, and State Plane coordinate system use standards, not coordinates systems to be used by surveyors on a day to day basis. State law can require that if a coordinate system is to be published on a map, that it meet a certain criteria, or that it be in a particular system for a particular type of map. The advent of GPS has had nothing to do with this. State Plane coordinate systems, their use, and the laws that govern them, have been around for years. What GPS has done is made the use of such systems easier, but assumed coordinates systems are still used on a daily basis because of their simplicity and ease of use.

 

- Kewaneh

 

I was refering to the use of GPS by the surveyor and the unacceptable use of local/assumed coordinates in its operation, which is considered bad practice. If a surveyor wants to use GPS for high accuracy work he is forced to use the WGS84 datum and some type of projection/coordinate system. In conventional work I know of very few surveyors that take the time/effort/expense to use an established coordinate sytem unless they required to do so.

Edited May 26, 2006 by stvanme