The Government has now mandated the control of piped water, storm water and waste water to itself. The avoidance of polluted piped water, the under-capacity of storm and waste water are necessary public health measures. But the shortage of water in most Territorial Authorities is shameful and the necessity to ration water when there is an abundance of water available is ignoring an obvious resource.

The fourth water is rain/roof water. Roof water can be harvested by every house or commercial building. Roof water can be collected in underground tanks filtered and available for garden and households alike. They are mandatory in Australia for firefighting etc. In New Zealand we like our gardens well-watered and producing healthy garden grown fruit and vegetables.

An obvious economy is water rates. Less obvious is the reduction of water to waste overburdening our piped wastewater infrastructure.

G Hodgson, Bethlehem.