Recycling tech exists so that net-water use can be zero or near zero. It's a matter of spending the extra money on it: it's cheaper not to.
The text presents a logical inconsistency. Here's a breakdown of the issues:
Sequence of Events: Joe drives Sue to the university and then returns home. This part is clear.
Inconsistency: The text states that after Joe drove home, he drank tea with Sue in the kitchen. However, Sue should be at the university if Joe drove her there, not at home.
To correct this, consider one of the following revisions:
Sue returns home: If Sue returns home with Joe:
"Joe drove Sue to the university. Afterwards, he drove back home with her, and they drank tea together in the kitchen."
Joe drinks tea alone: If Sue stays at the university:
"Joe drove Sue to the university. Afterwards, he drove home again and drank tea alone in the kitchen."
Either option removes the inconsistency and clarifies the sequence of events.