Surveyor's Footsteps: Keeping Current
King Solomon wrote “there is nothing new under the sun” in Ecclesiastes 1:9. I assume he read that somewhere.
When I attend a surveyor’s convention, there appear to be many new instruments, plotters, programs, tools and resources, all at ever higher costs. Land surveyors, like many other professionals, are to some extent pushed to make new purchases in order to stay current in their profession.
I tend toward using robots, and my initial purchase was fond of yellow school busses. Set up the instrument on a roadside and try taking shots and you could have problems. I learned to be more aware of when kids got out of school and planned on setting up somewhere else.
The first time it happened, I was shocked when I saw the robot lose its prism lock and turn to follow the bus as it zipped 180 degrees away from me. That would not be a singular occurrence. My second robot took no interest in busses.
Over time, I have learned to alter my approach and technique so that there are far fewer problems with locking onto something else and with reacquisition of the prism. I believe all surveyors continue to learn better ways to get things done and constantly look for “better mouse traps.”
I was given a CAD file recently while preparing a topographic survey of an old church in Philadelphia, at the request of an architect for his use in design work for the Pope’s visit. The architect was not sure of its origin and creator. The CAD file covered a portion of the church site, and I incorporated it into my work. I dissected the computer drawing and looked for markers used by the prior surveyor. This surveyor may have been a construction person and the plan must have been created for the contractors use. It was not typical of work other surveyors in this area produce.
After finding an old mag nail which appeared in the drawing, I set up on it as my first traverse point. I was very surprised at what I learned that day. It had been set in a joint in the sidewalk about a foot from the “X” in the sidewalk joints. Typically in the past I would have tended to set a mag nail at the X, but this person did not.
Since I am cautious about the potential of instrument legs slipping and the gun falling, I try to get the points of the legs into cracks. Using the mag nail, which I found to be about a foot off the X, I was able to put each leg into a joint. Try it some time. It worked well.
I can’t be sure if the surveyor knew she was placing the mag nail so that each leg would get a solid footing or not, but I want to think she figured this out, or she was shown this technique. It’s great to learn new tricks.
Twenty five years ago, I thought I had a novel idea. After finding a pin or stone in deep woods, I tied flagging onto the pin and then pulled a length out to tie it onto a tree limb. That way as I set up my traverse in woodlands, I could see the flagging tied high and follow it to the ground. The extra nickel’s worth of tape was a good investment in time saved searching the forest to see short wire flags or lath through the trees. Ten years later, I saw where someone else had used “my” technique and then I laughed inside and thought about how there is nothing new under the sun.
But putting a mag nail a foot off the X is new to me, and I will enjoy that for some time to come and choose to believe the person who placed it there was clever.
The Best Buggy Whip
If you pulled out a planimeter, would anyone under the age of 50 know what it is? Like the movie “Other People’s Money” where the star commented about investing in the last buggy whip manufacturer – but the very best buggy whip – I’ve seen some pretty fancy planimeters, some of which were electronic. I used them to scale areas from plans. We would scale a square and check our scale factor three times, then begin tracing around impervious cover or areas of steep slopes. Now I hatch areas on a plan and get square feet to three decimal places. It’s not really better; just easier. There is some value in realizing we can’t be too precise in everything we do, which helps us keep the spirit of the law and not always force ourselves to needlessly worry about the letter of the law.
Would I go back to my planimeter? Absolutely not. The same goes for using a transit and tape. It’s just too easy with the technology we have now, too fast and with far fewer errors. In many ways, the plans are not more accurate today than before. That is, provided the surveyor used good procedures to create the plans. Having come from the golden age of land surveying, I appreciate knowing that there are situations where a scaled area can be just as good as a calculated area.
How close is a tree? Using stadia and transit at 40 scale, trees are not much more accurate on our printed plans today. When I really want to be sure where a tree exists, I use the reflectorless option, set a 300 foot rod height, and locate its trunk three or more times. I can then create a three-point arc and inquiry the radius and place a node at the center of the arc. It’s a good way to locate a tree, but on my plans I have a standard note that the plan is not to be used for tree removal along property lines. The client must have the line field staked for removing trees. That way, when I come across a tree on or near the line, I can carefully think about where it exists in relation to the property line as I use a line stake routine.
After an engineer complained to my party chief about his inaccurate guesses of the caliper of the trees he had located on a heavily wooded college project, I suggested the three point method. The chief really went to town with his three points per tree and drove the CAD operator nuts. It became difficult to make him locate the trees in a more traditional way. The office person and the party chief have worked things out because the complaining has ceased. We all adjust, we all learn, and in every firm the field and office must progress together.
More Horse Sense
To be a great land surveyor one needs common sense. Some people call that “horse sense.” An experienced party chief will encounter a much wider range of experience in the field than an office employee sitting behind a desk. It’s important that field people appreciate how their time spent outside will have educational implications for the rest of their lives. Some people are more gifted than others and intuitively judge when something can’t work.
I recall in Missouri when the crew I was on had been given instructions by a recently hired field crew manager. He was a retired military officer who had no real surveying experience. The task the company’s civil engineer demanded was to measure the depth of a particular manhole. Of course they needed to know the invert because sewage flows downhill, and they were designing a sanitary run from the new subdivision. We were given our marching orders and told to get it done.
Our party chief arrived at the location of the manhole in question and it was paved over thickly. He drove back and told the supervisor it could not be opened because it was under blacktop. The officer, although smart, had no field experience and thus had no idea what it would take to open that manhole. We were directed, in no uncertain terms, to open that manhole and measure the depth. The civil engineer must have that invert elevation.
Armed with cones, a sledge hammer, and chisels, we took turns busting up the macadam. At the end of the day we returned with the measurement. It had taken our crew a whole day of hard work. As a reward for having a field crew spend the entire day opening a single manhole, the supervisor was let go. Once the experienced office staff found out it took all day, experience told them the new man was not right for the job. He could surely lead men into battle, but not into the surveying field. You must have a firm foundation of field experience to be a leader of surveyors.
Currently, I am meditating on purchasing a better mouse trap. During a discussion with my wife about the potential expense she asked “How long will it take to pay for itself?” I’m not sure it will catch me more dollars, and that’s my dilemma. It is pretty cool.