Traps in Surveying Definition

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Author

LPMS Admin

Published On

03/09/2021

It seems timely to have a short article highlighting what to many of us seems like the obvious.  The fundamentals of survey definition, although ingrained in many an experienced surveyor does need reinforcement not only for those well practiced but for those still gaining experience.  I believe these fundamentals also need reinforcement given the more modern Landonline environment we now live within.  Particularly regarding the pre-validation process and the temptation for some surveyors to treat it as a quality assurance methodology. 

The first fundamental that I want to touch on is the importance of a good origin whether that be in bearings or co-ordinates.  It is not unknown in rural areas that have had little recent survey activity that confusion can be generated around origin points and their related co-ordinates.  In class B or class C areas where co-ordinates are being sourced it is worth being certain of the survey description of a particular mark that you are assigning to a co-ordinate as mistakes at this point could lead you to be meters different from where your definition needs to be.  In other words, do you know for certain which mark you are beginning with? This may not necessarily be picked up by a pre-validation error due to a sparsity of information.  Deciphering old plans can be challenging at the best of times and so care at this point to ensure that you are certain as to your beginning point whether this be from a trig position or some other sixth order mark.  Mistakes at this entry point level could easily slide through the survey approval process at LINZ and may not become evident until LINZ are inserting the data into the digital cadaster, whereby at this point the survey may already be approved and deposited.  There is then the potential for the headache of a correcting survey and possibly a complaint being generated before the Licensing Board if the mistakes are numerous. 

Further to this, although surveying definition appears to become more and more mathematical as time moves on it is important to recognize that, where poor survey definition exists that the importance of long-term occupation is considered.  The importance of long-term occupation even in areas where survey definition is not limited as to parcels or of an interim nature, is sometimes not fully appreciated, especially by younger surveyors.  Situations where you are dealing with information from diagrams on transfer and shaky mathematical definition needs to be questioned when long term occupation is not matching.

The other important lesson from these surveys with challenging definition is not to be too proud to discuss these problems with colleagues as many of these issues can be sorted through sharing. If you operate as a sole practitioner, it is a very good idea to have other surveyors that you share these situations with.  Although I am not one personally, I am sure a lot of sole practitioner’s buddy up with others to allow this problem solving to occur. 

The other factor to remember is that with current high work loads it is tempting to short cut through processes around difficult definition with the intention of moving on to the next task.  This is a dangerous situation and needs to put in perspective.  You are better to go back and communicate with your client about estimated fees and if needed adjust anticipated costs to reflect the difficulty of the definition you are encountering.  This is a better solution that feeling pressured to limit your time and expertise to meet a pre-supplied budget. Haste will drive definition mistakes and is to be avoided for not only your professional health but also your own personal mental health as we don’t need to be before the Licensing board at any time explaining ourselves out of a corner.