Constructing new roads requires the use of a lot of water. If a new road is passing through an environmentally sensitive area, care needs to be taken to ensure that not too much water is taken from the local area.
The Eurotherm T2750 programmable automation controller (PAC) is used in Australia to provide high precision control of the heating process, which takes place during the production of laminated products, such as food packaging materials.
It probably goes without saying that there are very few linear position transducers that can withstand being submerged in 20 metres of water. And if you did come across such a device it would be very expensive.