Surveying land, the nuts and bolts?

I'm curious to know exactly how a surveyor maps out a plot of land. What is the starting point, what kind of marker is used? How does he/she measure from point to point, what kind of device is used, does it measure distance as well as angle?

I'd like to hear any relevant information. I'm in S. Calif. if there are regional differences.

John

 

jbclem,

it starts with a monument. A permanent fixed point used for reference. All new subdivisions have to have at least one. Depending how far the point (the monument) is from the lot or land you are surveying is, depends on the cost. if you read an assessors parcel map and your deed to the property it was based on 36 square mile townships and becomes referenced based on that.

If you read the legal description backwards it becomes easy to see how your property lies within the 6x6 grid of a township (36 square miles). All property lines are based on length and then a direction south, southeast etc... using degrees, minutes, and seconds.

With GPS available today many surveyors no longer have to worry about monuments as they can pinpoint one corner of the property and go from there. it is all math, angles and lengths.

The tools of the trade are a transit of some kind, which measures angle and distance. If they are marking lot corners they will mark with an iron pipe with their license number. They will set that pipe in one corner and then stake the other corners normally. If you are building you can have them set house corners or offset stakes.

It is costly but a key ingrediant to building on the proper lot and within the setback lines of a building envelope.

I hope this helps.

Brian Garrison
General Contractor/ Professional Building Designer

 

I'd like to try to find the monument nearest to a piece of property I own. Is there a way to look at the assessors maps in the area and spot the nearest monument? This is not a new subdivision, it's in Topanga Canyon

 

Or would I go to the part of the lot that fronts a road and look
for a monument at the corners? What would I be looking for, I think I've seen circular metal pieces (2-3 inches diameter) at ground level with writing on them...does that sound like one?

John

 

jbclem,

the 1-2" diameter pin with a civil number could be a monument. You can go to the accessors and see if they have a documented monument nearby. What I have always done is found a civil who had done work inthe area as he would have brought in a point to reference. He would trust his own work from the prior survey and you would save money.

The civils are liable and therefore trust only their own work. Again though if you work with a civil who has gps he does not have to bring in a point. He selects one corner and pinpoints it exactly with the gps.

I hope this helps.

Brian Garrison
General Contractor/Professional Building Designer

 

Brian, thanks for your help. My next question was going to be should I check with the assessors office for documented monuments...but you just answered that. Good information!

John