Leakage… that is my bet.
When I was living in Ireland they were transitioning from not paying water to pay for it as many countries. One of the reasons being the bad use of water by the citizens.
An independent study showed that the water system was faulty all over and it lose 30-50% of the actual capacity.
It usually rains that much in Belgium that they can waste lots.
In Spain we do not have that luxury.
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