Manholes and sewers gutters are important in maintaining underground pipe and sewage networks but their maintenance and repair is kind of problematic so most engineers try to avoid making one under roadways. These underground holes are necessary where a sewer line changes direction.
Now the problem is that manholes on roads tend to sink deeper and deeper over time and need to be raised on a regular basis. The huge machine in the video below is perfect for this function as the crew drills out the manhole in an attempt to raise it. Have a look:
This machine is a giant saw specifically made for cutting concrete and manholes. It is used to either replace and repair old manholes or install new ones. The cutting head of this saw has a diameter of 5 feet and can drill into 14 inches of concrete in just 1.5 minutes. When the cutting is completed, two small arms under the head of the machine will lift the concrete and old manhole to deposit it at another place. This clears the area for repair and engineers can go about their work.
Pretty cool, huh?