Back in the day, construction was a business that involved a lot of trial and error. When building large offices or apartment blocks, there were no clear ways in which to accurately take measurements on the go. This led to a philosophy in the construction business that they had to leave room for error. This also meant that things like the excavation for the laying of foundations was pretty hard to do. After all, the tools that were in existence for the excavating of these holes were the huge arms of the backhoes and the smaller pickaxes and shovels that the workers on the site would use. While all of these were great for burrowing, they would usually result in laying waste to a large swathe of surrounding area. Any nice trees nearby that the owner thought they could preserve, for instance, are going to be in a lot of danger.
Water has power beyond what you think
However, this does not have to be the case anymore. With the recent advances in science and technology, extensive research has been done into the power of water to wear down hard surfaces. For example, the constant flow of water in a river has been known to cut channels through the hardest rock. This is one of the reasons that you are able to find gold deposits in some rivers: the water has cut through caves that contain the ore in large amounts, and caused some of it to flow out with the river. When it comes to junk pick up in Melbourne methods are now preferred, because it is so much cleaner, safer and more accurate. Some people have started to harness the power of water in order to dig holes with precision.
Scientific facts prove this
This is actually one of the simplest laws of physics. The force exerted by any object on a unit area is equal to the pressure. This means that a higher pressure of water will exert a much larger force on the area. If the stream of water that is made to shoot out is of a tiny surface area, then the force it hits with will be far higher. In fact, it will be so high that the stream of high pressure water is able to cut through steel and rock with the same amount of effort as a hot knife through butter, this includes with liquid waste removal. When this is employed in fields like digging non-destructive cuts are achieved in the ground, no matter the texture or hardness of the surface. If you are in the construction business it is time to switch over to the cheaper, more precise method of ploughing holes in the ground and in the street.