After thinking about this for a while. I don't know about you guys but most of the plans I get now days a virtually impossible to build of the hard copies. Key dimensions left off, incomplete data, just a picture for the surveyor to figure out.
Ron Lang, post: 374186, member: 6445 wrote: After thinking about this for a while. I don't know about you guys but most of the plans I get now days a virtually impossible to build of the hard copies. Key dimensions left off, incomplete data, just a picture for the surveyor to figure out.
In fact just a week or so ago I was hired to layout a couple hundred feet of waterline and a couple fire hydrants. The plans had b & d on all the property lines showed existing features such as buildings, curb, islands, manholes.
This was a rush job so i didn't ask for cad files, which wouldn't of helped anyway. I get to the site look for corners and find none. No control shown on plans. In fact the plans did not even dimensionally locate the water line. So to calc, I put the property in cad, scan the plan, and scale to fit. I always, put points on bc, mh, pp, and defining curb points in case I cant find control.
I ended up using a few manholes and building corners to establish my position. Start laying out my waterline and low and behold the fire hydrants are in the parking lot, 7 feet away from the island it is supposed to be in. The wl doesnt match the physical location.
Long story short, lol. I called the engineer and he said oh that waterline was an after thought and the did use actual field survey locations for the design, they used GIS data. I said no sh#$. You also have you vertical datum off by 100' or so.
MORAL we are only as good as the information we rely on to do our work properly.
I'm not sure why folks keep repeating the 'staking from CADD without checking' thing. Nobody has advocated that.
Some places haven't made the leap to digital yet, but others are there. We have digital recording in several states and models are used on most local construction sites. One of our jobs has three people laying out. The only ones not using a model? Us. We are working from an ACAD file that has been checked and is continually updated. It works just fine. There is no difference failing to integrate your bulletins with your plans than dropping the ball in CADD.
I was asked by an engineer to help stake a power line, I was emailed an excel file with the structure locations and guy wires and another with control points with UTM coordinates. The next day the engineer and I went out and he showed me a few control monuments. After locating a few control points, I determined the coordinates to be grid. I called the engineer to verify that he was working in grid not ground. He had no Idea there was a difference. After staking 10 or so structures I reached an existing P.I. structure previously staked which didn't match by several feet. That night I imported the points into a cad file that had been emailed to me during the day and checked the location staked with the drawing. The next day I brought up the PI structure not being in the correct location. The engineer went and checked his staked offsets to the pole and said the pole was correct. He had staked 8 structures perpendicular to the line I had done with his total station. It took me several hours to convince him and the electrical company engineer that the ground and grid measurements differ. While this conversation took place the contractor set 5 or so poles and realized they didn't line up. He called me and both of the engineers who decided to hold the already set PI poles for line. Thanks to the drawing I proved the coordinates given to me matched the cad and didn't line up not to mention the poles previously staked at ground distances. What a mess. I had many engineers ask for state plane on a design projects. I always hold one control monument where grid=ground and use ground for the project. I guess it makes sense to use UTMs for long power lines but the engineer should have known the structure spans would be at ground.
Ron Lang, post: 374186, member: 6445 wrote: After thinking about this for a while. I don't know about you guys but most of the plans I get now days a virtually impossible to build of the hard copies. Key dimensions left off, incomplete data, just a picture for the surveyor to figure out.
So what are some of your options here?
- Stake from the CAD drawing that you may have checked 20 different ways and believe to be correct?
- Design a solution that works like a charm?
- Send an RFI to the engineer requesting the missing information?
Each option has itÛªs pros and cons.
1. Stake from the CAD drawing.
Pro: The contractor will like you for keeping things moving ÛÒ if you see him in the local watering hole, heÛªll buy you a beer ÛÒ he may even want to keep working with you (as long as your price is the lowest or very near it) ÛÒ possible long term client ÛÒ To me, this is the biggest temptation to stake from the CAD drawing.
Con: If this drawing is in conflict with the sealed document and something goes sideways ÛÒ itÛªs all you. ItÛªs not you and your insurance company ÛÒ itÛªs all YOU. Your professional or general liability insurance wonÛªt cover you working off of unsealed documents. Additionally, you may be subject to disciplinary action from your licensing board (or your boss will if you arenÛªt licensed) for negligence.
2. Design a solution that works like a charm.
Pro: YouÛªll be the hero and youÛªll be subject to all of the other pros listed above.
Con: Unless you are a licensed engineer or your state regs allow you to that type of design ÛÒ itÛªs all you. Once again, itÛªs not you and your insurance company ÛÒ itÛªs all YOU. Your professional or general liability insurance wonÛªt cover you for work that you are performing illegally. Additionally, youÛªll be subject to disciplinary action from your licensing board (or your boss will if you arenÛªt licensed) for unauthorized practice.
Even if you can legally perform that design work your insurance company may not cover you for work that is outside of your scoped activities.
3. Send an RFI to the engineer requesting the missing information.
Pro: You wonÛªt risk your business and your personal wealth. Your insurance will cover you because you are not working outside your scoped activities or the law. The owner will get the professionally designed improvements that they paid for. The licensing board wonÛªt be taking action against you.
Con: The contractor probably wonÛªt buy you a beer. If you didnÛªt do your comps early in the process, this may delay the project (and some will say itÛªs your fault ÛÒ but itÛªs not).
Additionally, if this is a recurring problem or if the engineer is not responsive, this should go to the state licensing board. The engineer has an obligation to provide sealed drawings that are complete and constructible.
When you stake from anything other than information directly on, or derived from, the sealed plans, you are taking on a whole lot of professional liability and probably personal liability too.
Ron Lang, post: 374186, member: 6445 wrote: After thinking about this for a while. I don't know about you guys but most of the plans I get now days a virtually impossible to build of the hard copies. Key dimensions left off, incomplete data, just a picture for the surveyor to figure out.
Before cad the drawings did not scale as well. After cad they scaled much better. If there were no dimensions we got er done one way or another. I think people who are using the cad to do layout think they are using a correct procedure (compared to simply scaling). Either way is wrong, but we as the construction layout surveyor should not have to continuously try and explain why there is inadequate data on the plans to layout from. The surveyor is still the step child of the engineer and is just ignored when it comes to what is needed on the plans to accurately construct. In fact a past engineer I worked with stated after I commented on lacking dimensions on her plans "the plans made it through the agency plan check, what more do you want". The point of plans was directions to build from at one time, now they are nothing more than a procedural product so the local agency will allow one to develope. My 2 cents, Jp
Some DOT's are working toward making the I model the official contract document. The times, they are a changin'. Do your best to keep up.
We simply do not stake other firms data. Two factors are involved in that decision: 1) staking for others is typically a process that involves bidding and we do not bid on work. 2) Staking data provided by others is not worth the headache.
I have worked at places where we did provide staking for contractors based on plans supplied by others, it rarely worked well.
We only stake our own designs these days and the plans reflect this. Why label each and every intimate detail when it is not needed...of course this is only applicable when the staking is done in-house.
