Leaky pipes are small beer compared to the ~Billion GL lost since late 1990’s by not managing catchment bush.
I have written often on this issue over many years – Update 39 years of Perth dam catchment rain index 1975-2013 – has links to my letter and reply from WA Water Minister – plus some other key links.
A few years ago when Adelaide faced water shortages there was an advertising campaign from the State Government about saving water. This was the excuse to build a desalination plant, which was later (very quietly) doubled in size to match the existing supply. The Gov. backed this up with restrictions on using hoses, watering gardens etc. Indeed we still get messages on our (much increased water bills).
The desalination plant is mothballed and all we have to show for the cost is the extra water charges, but what they tried to hush up was that household use in Adelaide was 6% of the total, and that wastage from burst and leaking pipes amounted to 6% also. I think there was a cheaper way to double the supply.