Water update...

It has been a while since I've done a water update...

Sydney Water: based on data from the last 8 water bills we have used 122kL over 646 days or an average of 189L/day. We have four people living here so individually we average 47 L/day.

Comparing those numbers is a little tricky. Sydney Water data indicates that an average dwelling uses 623L/day. They also provide water efficiency targets by season, number of people and property size. For our property the comparison is > 900m² with 4 people.


Sydney Water efficiency targets by quarter (L/day).
QuarterSydney Water TargetTPH actual
Aug - Oct556253
Nov - Jan572195
Feb - Apr576187
May - Jul535167

Despite by best intentions I have not yet put into place the software to measure the rain water tank usage directly, but I do have a system that measures the water height in the tank (Vegetronics) and a NetAtmo rain gauge. 

The rainwater tank sensor reports full slightly below the actual full mark, so there is some truncation when the water tank is full. While individual rainwater tank water height sensor measurements can be a bit noisy, as a daily average like plotted here it is very reliable through most of the range. We have only run the tank dry twice, and we use rainwater for laundry, toilets and gardens >98% of the time.






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