A common misconception is that drinking water is an important source of essential minerals for the human body. While many minerals such as calcium, magnesium and sodium can be obtained from drinking water, research has shown that mineral uptake from tap water is very low. An adult can generally fulfil between 5-20% of their recommended daily intake of selected essential minerals by drinking tap water
This is provided they drink 2 litres of tap water per day and that the tap water has a relatively high mineral content. Most cities in Australia have low mineral content, partially due to the water source and the water treatment process; making it unlikely to even achieve these levels. Bear in mind there are only a select few minerals contained in tap water, while a great many are required, and essential for the basic functions of the human body to complete.
The main source for these essential minerals is from the food we eat, not from the water we drink. A balanced diet is the best method to providing all of the minerals our bodies require.