Invert measurements can be a pain. Underground structures and manholes are dark, hard to reach and often filled with garbage, water, mud and other things i try not to notice as they float by. We would use measuring rods but on recessed pipes and structures we often still had to mentally straighten the rod and estimate the vertical distance. But wait! Then we received this amazing clip on attachment that fixed everything.....sorta. It turned out to be quite bulky, heavy and took some practice to maneuver it into the structure. While on a site with multiple sanitary manholes i couldn't help but notice that our new tool also appeared to act as a ladle, bringing the wonderful content of the sanitary structure to the surface where i would then have to remove the attachment. The tool quickly fell into disuse and remains in our storage closet. There had to be a better way.
My father, who has been surveying for over 30 years, also recognized these problems so together we decided to find a solution. We developed a new tool and methodology that allows for quick and accurate vertical measurements at any angle. But what makes it even more unique is the ability to quickly achieve a redundancy of measurements as well as office checks so that you will never have to return to a structure in order to verify information. I urge you to read this article and please reach out to me if you have any questions or concerns. I would be incredibly grateful to hear your feedback or experiences concerning invert measurement. Download Accurate inverts article.pdf