Water tank for retic

Hi, just seeing if anyone has any experience with using stored water to run reticulation?

I’m going to set up retic to water about 1700sqm of lawn this winter. I know it is a fair bit of lawn, but it is pretty well shaded and I don’t think it will require heaps of water, but it does need some and I’d like to do something about that.

The small lawn area and garden around the house is set up to water off mains.

Initially I was going to put a bore in and run it over 3 stations, however checking the neighbour bores they are very high in iron, and outright it’s terrible water, not to mention it stains. Asking around the water table is getting lower and lower and a lot of the older bores are getting drilled lower.

Anyway, I have a 150sqm shed, was considering putting about 70KL of tanks on it and using this to water the lawn. I can add to this if I need. I calculate the lawn would use about 6000L a week if it was watered 20 mins twice a week. Which would mean I’m out of water in 3 months assuming no rain, which is not uncommon. Someone better with water usage might provide better insight than me at this.

Alternatively I can use a bore to add to the water tanks in the middle of summer. Kind of beats the point of it though – not sure if a filter or something would be worth thinking about.

Economically it seems stupid, but I guess if it is a contribution to saving water then it might be worthwhile. Money is not the overriding issue but it’s also not a bottomless hole.

Thanks