Drinking water reservoirs

The constraint that comes before everything else

A coating in contact with drinking water must not release substances into the water, alter its organoleptic properties or encourage microbial growth. The most widespread European technical reference is the German DVGW certification, in particular the W-347 and W-270 worksheets, which assess respectively the release of substances from cementitious materials and microbial growth on surfaces.

This is a requirement that narrows the field drastically: many excellent general-purpose products are not permitted in this context, and verification must be done on the individual product and its specific certificate, not on the family as a whole.

The two routes

The first is making the structure itself waterproof, with a crystalline admixture dosed at the plant and a declared suitability for contact with drinking water: no coating to maintain, no interface that could detach.

The second is an internal coating with a certified crystalline or cementitious slurry, which can also be applied to existing structures and is the obligatory choice when renovating a reservoir already in service.

Scheduled maintenance

Drinking-water reservoirs must be periodically emptied for inspection and cleaning. This is the window in which any work is carried out, and its shortness drives the choice of materials as much as the technical requirements do: speed of return to service matters as much as performance.