The sensory properties of natural waters

The sensory properties of waters involve those which affect the human senses, particularly taste, odour, appearance and touch. Among these temperature, taste, odour, colour and turbidity, are important characteristics. 

Depending on the type and source of water its temperature may vary over a wide range (from 0 C to almost the boiling point). 

Running surface waters follow the minima and maxima of the atmospheric temperature. 

The temperature of waters in reservoirs decreases with the water depth from the surface. The temperature of surface waters varies strongly during the seasons of the year as well as during a day (within a range from 0 to f 25°C). The temperature of surface waters strongly affects the intensity of self-purification processes the lower the temperature, the slower the rate of these processes. 

The optimum temperature of drinking water ranges from 8 to 12°C. Water which is warmer than 15°C is not refreshing [8]. 

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