A big problem is that the lawyers toss a net over all the names attached in some way to a project hoping to catch as many as possible who might have some assets worth going after.
A good general rule of thumb (that has saved my bacon over the years and taught to me by a mentor very early in my career, many moons ago): Always check your work with "fresh eyes", and always double check everything.?ÿ If, when looking at whatever the task at hand was at the time, something doesn't "feel right" and you have that gnawing feeling in the pit of your stomach that you missed something, you probably did. It's weird, but over time you really do develop a "sixth sense" (probably in every profession, but due to the potential litigious nature of our work it's probably a heightened sense in Surveying). Hope this helps
My biggest mistake in 22 years from a liability aspect was on a topo, where I thought the liability would be less, but maybe that's why I f**d up.?ÿ
The site was a acre lot that sloped down from the road to a steep bank 20' high above a rocky beach. The crew cut parallel lines through very thick brush about 10' high to the bank, then traversed down to shoot the beach. At the end of each parallel line was a shot labeled "TOP". All the TOP shots made an almost straight line except one. It was about 20 feet back. When I drew it I assumed that the crew missed the last shot, so I drew a break line across the short cut line. WRONG. There was a small canyon that I missed. When the lot was cleared and being excavated, I got a call from the owner. "I spent $500k on the lot, had the architect design my house, the excavator is working, 5 containers just left Miami with building materials and none of it is any use to me because the pool can't be built in the canyon."
I didn't hear from him again, the house (and the pool) got built, so I assume he realized there was only maybe $10-20K of extra concrete for his $2M house and he moved on.
99.9% of the time, you don't have to be accurate, you have to be right. And accuracy helps you to be right and avoid the big mistakes.?ÿ?ÿ
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I once had a couple of crews clear a 50' grid across a 2 acre site.?ÿ The undergrowth was so thick I believe it would have been impossible to even crawl through it.?ÿ The work was tough but I eventually had stationed grid lines I could see through.?ÿ We completed our topo and I even personally walked the grid lines several times before we turned our work over to design.
With all our best efforts we still missed a good sized drainage wash.?ÿ We caught it early on in the project but I was still mortified.?ÿ I realized there could have been a structure hidden in there and our method would have missed it.
Live and learn.
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My worse mistake that I got caught on was a lot job. I tied two found pins located at fence corners and calibrated to them to search and reset lot corners. The neighbor noticed my lathe on his property and hired his Surveyor to check my work. His Surveyor called me and informed me there's something wrong with your survey. What! I never make mistakes. We met at the job site and he showed me another pin 8 feet away. My face is still red 5 years after.
When I preformed the calibration I had failed to hold the scale factor to 1. Of course then everything checked out perfect. Once I corrected that problem. You only have to check the box to hold the scale factor to one. I ended up finding all the old lot pins.
Still feel like a fool.
I've made thousands of mistakes, some lessons learnt,
- Never be afraid to ask questions and seek information you don't know from your team or site engineers or equipment specialist, be very confident in what your doing and make sure you've done everything you can to know that your work is correct
- Cross check designs civil and architectural (architectural overrides civil plans), be extremely thorough when calculating any set out data
- The usual field checks, check shots, and target height checks but more than that I relevel and reset up after my set out to do a few checks as well, it is possible for your set up to be wrong but your check shots will come in as if they are correct, this can happen in a few ways and its tripped me up a few times
- project site establishment has been a new one for me, including boundary definition control network and running through the initial ground works, for a project control network you base your traverse to run around the perimeter of the boundary surveying boundary marks for the definition along the way, from there traverse into the project to extend control where needed
- I would take the time to understand boundary definitions and run through the whole process of defining a boundary with a registered surveyor, this will give you some invaluable knowledge, especially all the designs/documents you need when first taking on a project
- Never set up on Ashfault
- Never trust anyone meaning pedestrians/construction workers/ your team mates near your total station they will bump it, don't be afraid to tell anyone to get the fuck out the way of your line of site, no time for it
Just some things to note is that there is always something in your surveying you can be doing better/more accurately or efficiently, always seek to find different methods of doing one task, no survey task is cookie cutter, every project is different and needing the same stuff but you'll need to do it differently to make it work.
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As everyone knows, a traverse closure can close even if your calls are out of order. The obvious problem is that a perfect mathematical closure could still have huge gross errors on the ground.?ÿ
One of the biggest mistakes is to trust that what others provide to you is correct and complete, including the boundary.?ÿ Finding the other guy's pins and holding them can cost you big time.?ÿ If he made an error, you made an error and will be pulled into the same law suit by the adjoiner.?ÿ A simple example is a current deed that suggests a certain line runs down the center of Lot XX.?ÿ An inspection of the current deed says that boundary is for the East Half of Lot XX.?ÿ But the lot is significantly longer than what the deed says and the first deed says?ÿ "The East XX.X feet of Lot XX".
When you are doing calcs from design drawings for setout - always get a second pair of eyes to run over it, even if you have to hire someone from overseas. Much cheaper than paying for a stupid setout error! and underlay the pdf if your CAD package allows you to do this
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Note--I have never attempted to use this so I cannot comment on its implementation.?ÿ I have also never seen it implemented or spoke with someone who has.
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Per the SurvCE manual:
"Activating a laser for use with a robotic total station follows a similar procedure. Attach the laser
to the prism, pointing towards the ground. Every total station read will automatically trigger the
laser, and the read value will be used as the rod height."
p.242
http://survce.com/SurvCE%206.0%20User%20Manual.pdf
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On uneven/grassy terrain, I actually think it would be worse.?ÿ It would be nice if you could set it to check the entered rod height +/- an amount of your choosing.?ÿ Ie. flash a warning if it detects you're out by 8" or so.
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Side note--I usually find that trying to only use the 4 preset rod heights in SurvCE eliminates most errors (ie. you know the measurements can be corrected to one of those if the height was entered incorrectly).
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I believe construction layout is the cause of approximately 75% of all insurance claims in our profession here in Ontario.
"Construction layout is and continues to be the largest source of claims against our Insurance Fund."
p.6 onward
https://www.aols.org/site_files/content/pages/about/media/ops-magazine/summer2019.pdf
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Year Incurred Losses # of Claims Average Claim $ Legal Fees 2010-2011 $1,400,000 64 $22,000 $435,000 2011-2012 $1,020,000 51 $20,000 $180,000 2012-2013 $1,050,000 70 $15,000 $160,000 2013-2014 $820,000 70 $11,700 $175,000 2014-2015 $800,000 56 $14,000 $195,000 2015-2016 $535,000 57 $15,000 $120,000 2016-2019 Undeveloped Undeveloped Undeveloped Undeveloped
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To the OP, by those current stats, not pursuing construction layout would likely result in a lower chance of being in a situation where a "big mistake" occurs.
Ouch.?ÿ I'd say, thanks for sharing, but now you've just scared the crap out of me.?ÿ Kind of glad I'm not an owner
