I think that one reservoir will not be enough and a second or even third should be planned in a 25-30 year timescale as the amount of housing that is being built especially in Welbourne Fareham and in other areas in Hampshire over the next 10 years will put a greater strain on our water supply.  All new houses should have mandatory water meters, and agree that change of ownership of property should include change to a water meter they are a good way forward and resources saved on meter reading could be used in other areas.  I think that 15% reduction in leaks is good for moment but a plan for further reductions up to 50% over next 25 years could be way forward, plans to replace old pipes on a general maintenance plan would also help in the reduction of leaks this could be a long term plan but  will show that you are taking water conservation very seriously.