Posted By Jeremy Lipke on 1/22/2009 at 5:24 PM
my area the mapping that the aerial companies provide always seems to
lack a statement documenting the basis of elevation and coordinates. No
basis of bearings. No published coordinates for the survey control. The
work is basically floating in space with no way for a surveyor to tie
it back into the ground.
I have seen where engineers design
large projects on top of the electronic drawings that the aerial
companies provide without a clue as to how it relates to the ground
come time to construct the project. Someone knows this information, but
god forbid they retire, the files are lost or they go out of business.
Is this common? JRL
January 23, 2009