Water destined for human consumption must be germs and bacteria free, and exposed raw concrete, due to its ruggedness, creates sources for the developement of baterias that affect the water's healthiness.
On the other hand water load variations as well as temperature changes can create cracks, an it is necessary to avoid the risk of corrosion of the concrete's steel.
Furthermore, over the years deposits and cisters usually show leaks because they are not monolithicaly built.
Because of these things the correct waterproofing of any deposit, cistern or pond that will be used to store water is essential.
These systems are certified to be:
> Permanent contact with potable water for human consumption.
> Permanent contact with food products.
> European certificate for the protection and repair of concrete structures
On top of holding ETA certificates with an estimated useful life of 25 years.