WHY IT'S IMPORTANT TO FLUSH YOUR TAPS
Many natural New Zealand waters tend to be "soft" with moderate to low levels of alkalinity and pH. These properties can give the water the potential to leach metals from taps and other plumbing fittings when water stands for several hours, for example overnight, (ie. are "plumbosolvent").
To ensure that any risk from higher levels of metals is avoided, the Drinking Water Standards of New Zealand requires that Drinking Water suppliers pass on to consumers the following message from the Ministry of Health.