Composition of mountain water
The mountain water of the bypass Visp (road tunnel in Switzerland) is supersaturated with lime and causes, without any additional external influences, deposits. As long as the composition of the natural mountain water will not change in the future, the formation of deposits will continue unchanged.
It is very difficult to achieve a positive influence on the composition of the mountain, because the quantities which are required to influence the composition significantly, are very high (for example, removal of the lime out of the water). Implemented is the addition of additional water in the drainage system (at the start). By mixing two different waters together (in total) we will get always less deposits as when we separate them (in the sum).
So it makes sense, to connect the individual sections of the drainage system to each other. A negative influence of the composition of mountain water is much easier to realise and can be observed anywhere. By the contact of the mountain water with the CaO-components from the shotcrete, the amount of calcium dissolved in the mountain water increases.
A thick shotcrete is the best measure against the undesired saturation of mountain water with calcium compounds. However, income and expenses, should be estimated in advance.
