- SPECIAL REPORTS
- THE MAGAZINE
On pirate maps, “X marks the spot.” When entering the main doors in most large malls across America, we find the information board with a map and key to help us locate a store. Our survey plans often have a location map. In parks there will be a placard with a big arrow that says “YOU ARE HERE.” These are all a necessity to find the place we seek.
A director of surveys for a Maryland firm told me about a time when he had a crew stake out a sanitary trunk line and things went wrong. It was probably marked with 8- or 10-foot offset stakes and it was a long straight run. After a large portion of the pipe was constructed, the contractor realized the pipeline was on the wrong side of the line of offset stakes. That would make it 16 or 20 feet from where it ought to be. In my area of the country a 30-foot-wide easement is large for a single sanitary line, and, at 16 feet from where it was intended, it would be outside the easement. I feel sure anyone reading this knows that the contractor tried to blame the survey crew.
After listening to this sad story, I decided to routinely set a stake at the rough location of the objects I am staking out. I just don’t want to receive manipulative phone calls from managers of poorly supervised construction crews.
For a proposed manhole I will place a lath and tie a different color flagging on it than the color I used for the offset stakes and mark it “PROPOSED MANHOLE.” At proposed inlets I will paint a white rectangle on the ground and cross hatch it. For “dig stakes” set for a deep dig on a house basement, I like to paint in short lines pointing from stake to stake so the dozer operator knows how the corners lie. There are times when I am asked to rough stake for footers in a basement hole, and I will set the outside building corners and paint not only the direction from corner to corner, but often the inside wall line so they know without a doubt what I was marking. You could say that I do this for them as part of the service, but really and most importantly I do it for myself.
Some years ago, I sent a competent crew chief out to stake a silt fence at the start of a large municipal park project. The contractor wanted to install the erosion and sedimentation controls. Along the property line were small trees and a lot of brush that needed to be cleared to install the fence, which was 5 feet off the property line. I instructed the party chief to use the line stakeout routine on the instrument and find an offset line that would allow him to give the contractor a long straight line to measure from. He came up with a 30-foot offset line, and it was very visible in the short grass. Anyone looking at the plan would know that the silt fence line was in the vegetation along the obvious property line and not out in the open field. I believe that anyone looking at a copy of the plan would know the silt fence belonged in the brush and not running through an open field where ball fields would be constructed.
So where did the construction crew put the silt fence? Right down the line of offset stakes. To make things worse, it was super silt fence that was installed on the equivalent of cyclone fence. To make things even worse, hard shale was under the thin layer of topsoil so it was very difficult to install.
The contractor called cursing on the phone about 5 p.m. He really gave it to me for the error in staking the line and probably informed me it would be my cost to fix things. I was polite and told him I would go and check it out. I really like this contractor and he is a Cracker Jack operator. When he is on the job, I know things will always go right, or he will correct things and make field decisions that can be relied upon. In this case, he was elsewhere when the installation took place and one of his fellows phoned him to say things had gone wrong.
My father, a retired PE, taught me that it is best to examine yourself first to see if you have made a mistake and try to prove yourself wrong three times before telling someone else they are in error. In order to determine any errors my field crew had made, I drove out immediately to the job site to see what had happened. Upon arriving I saw the fence was obviously in a wrong location. The fence posts were gnarled on top from all the force necessary to drive them into the hard shale. The lath were clearly marked “30’ offset to silt fence” and flagged well. I took photographs of the markings on the lath. I called the contractor and told him the situation and he began to tell me that it said 30 inches and so it was the line staked out for a 30-inch silt fence. I don’t know a contractor in my area that does not know the offset symbol. It seemed this was going to lead to a long argument with this ordinarily great fellow.
Later that evening, I received a second phone call from that contractor. This time he apologized for what he had said earlier. He agreed that it was well marked and his crew was sent out by a foreman and they did not know what they were doing. There had been no field supervisor. Had my crew chief been able to set some stakes and mark them, “Silt fence to be installed here,” the problem might have been avoided; but then again, maybe not.
When the surveyor with the trunk line problem explained it to me, I thought back on the silt fence line. We often don’t see the person using our stakes. Even though they are emailed or faxed copies of field notes, we cannot be sure the field people actually received our notes. Letting an “X” mark the spot may help out an inexperienced person and save us headaches.