Having read the 2018 Water Conservation paper which concentrates on the responsibility of water authorities to control leakage and give advice to consumers about saving water I believe legislation is required to ensure potable water is used appropriately and promote the use of rain water.
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Suggestion:
1. All dwellings with a garden must have capacity to store at least 200 litres of rain water collected from the roof.
2. Preference should be given to allow any excess rain water to be directed to soakaways to improve water table levels.
3. All businesses with enough roof area should collect and store sufficient rain water to last at least a week for flushing toilets before having to revert to supply from the authority.