Copper pipes are used extensively in plumbing systems in Australia (and internationally). Drinking water can contain elevated concentrations of metals such as copper and sometimes lead when left standing in pipes for extended periods. In this case, it is a good idea to flush cold taps for 2-3 minutes before using the water for drinking or cooking. This will lower the levels of copper and other metals that may be present in the water. This ‘first-flush’ of water can be used for washing up, watering plants, or other non-drinking uses.
Visit the NSW Health website for more information.