Concrete mixture water is a very sensitive and important raw material used to provide the workability of concrete and to ensure cement hydration. The reason for being sensitive and important is the fact that the amount of water can affect all properties of fresh and hardened concrete.
 
Concrete mixture water should be as clean as possible and there should contain as much substances such as chloride, sulphate, acid, sugar, organic materials, industrial waste, oil, clay and silt which may be harmful.
 
Cement requires up to 25% of its weight for hydration. Water used more than this amount is only aimed at increasing its workability. This, by time, leaves the body of the concrete, leaving hollowness in its place. The greater the amount of mixture water, the greater the hollows, and this not only affects the strength, but also affects the durability of the concrete negatively.

It is used for three different purposes in concrete production:

• ♦ As "Mixture water" in the mixing of concrete with cement and aggregate.
• ♦ As "maintenance water" applied to the surface of fresh concrete placed in its place.
• ♦ As "washing water" to ensure that aggregates used in concrete are clean.

The most important of these is the first one. In other words, wetting the surface of cement and aggregate granules, it is possible to easily mix and place concrete materials, in short ensure its workability.

The water to be used as "mixing water" in concrete production should be as clean as possible and should not contain organic and waste materials that may damage concrete.

The water to be used in the production of concrete must comply with TS 3440 and should be potable in general.