Water for concrete
Water is needed in concrete for two reasons, firstly to hydrate the cement and secondly to provide mobility when the concrete is in its fluid state (workability). Generally the amount of water needed for mobility purposes is greater than that required for hydration only. The water used should be clean, i.e. of drinking water quality, but other water is allowed by concrete producers by following BS EN 1008.
Many properties of concrete are affected by the water content, and more particularly the water/cement ratio.