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Sorry for the newb questions but i was wondering how bench marks are marked on prints....im just learning about elevations and such but im currently laid off so i haven't any prints to look at to try and figure it out....is thier a universal symbol?
 

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Vagitarian
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I usually use a exsiting manhole lid as a BM. I always have the surveyors throw some stakes in with BM's on them.
 

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It is a triangle with a dot in the center.
You can use any fixed object for your own benchmark onsite, but you must extrapolate the elevation from the called out benchmark,.
 

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The triangle is the universal mapping symbol for any type of randomly located survey control point, which includes all geodetic markers, waypoints, traverse stations, etc. whereas the square is used for points that are not set at random locations, such as boundary corners. In fact, many surveyors refer to random control points as deltas, due to the shape of that letter of the greek alphabet.
Around here benchmarks are usually notated with an inverted cone shaped symbol; the point of the cone being at the bench mark with the base of the cone above the location. Typically the bench mark is identified either by number ("BM 1") or name ("BM Bo Didley") and is described by physical characteristic (cut nail in SE side of 24" oak, square cut in top of curb, bonnet bolt at face of fire hydrant, "X" cut in manhole lid, etc.) and elevation. Plans which depict multiple benchmarks often include a table of benchmark data
 
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If you were ever in a situation where you really needed a true elevation to come off of and didn't have anything on plans you could always go on usgs.gov. Its pretty sweet you can search your entire area for monuments or "benchmarks". I actually did this when i was looking to buy my house as i wanted to check the floodplain elevation of the house.
 
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