Every time I try to out-guess mother nature, she makes a fool out of me.
For example, I once had a client in Nevada who needed foundation recommendations for a lightly loaded structure that he wanted to have built. He described the site to me and based on my experience with similar sites in the Nevada valleys, I told him that we should be able to accomplish what he wanted with a series of test pits. The area seemed to be typical of the valley-filled sediment areas so common in Nevada. I sent one of my engineers out to inspect the excavations. Naturally, I would have preferred to use a geotechnical drill rig, but I was deferring to my client’s very limited budget.
What my engineer found had confused him. He showed me a bag of the material that was obtained from the excavation. It was sand. Sand dune sand. Nope, we’re not building a structure on shallow foundations on a sand dune! We had obligingly saved the client money on the site investigation, but we were unable to design the foundations that they needed based on the information we were able to collect. They did not retain us for any additional work, and I often wonder if some poor outfit had designed the shallow foundations that the client wanted on those sand dune sands. Plus, I had really guessed poorly on what mother nature had done.
Lesson: do the diligent work that is needed for a project. Don’t let mother nature fool you.