I think that reducing leakage by 15% is a relatively poor target. I think that your target should be much higher, particularly given the waste each and every day. The water lost due to leaks each day is worth 250,000 houses use of water per day based on your calculation of 140 litres per day. Reducing this by 15% means that 212,500 houses worth of water each day would continue to just disappear... try throwing that figure around when you are asking people to restrict water use and get water from standpipes in the street. That is not ok. It should be an incremental reduction. Eg. A strategic plan to reduce leakage by increments each year. Eg. 20% by 2025, 30% by 2030, 40% by 2035 etc. Breaking it down in this way will make it more achievable and you can approach it in a strategic manner. There should also be publicity campaigns to encourage the general public to report leaks and how. I.e. a free number if you see a leak. It should have the same gravitas as a gas leak. It may not be fatal now, but in the long run, it WILL affect our livelihoods and people should be more aware of water. Adverts about not running the tap when brushing your teeth, using tumble dryer water to water the garden, how to save water etc

In terms of increased use of groundwater, there needs to be transparent work that goes into ensuring the quality of groundwater used and work towards reducing pollution which affects this groundwater.