Ms Maria Graham:

Self-declaration, with some auditing, is usually the most cost-effective way of dealing with something if one is dealing with a large population cohort. It works very well in other regimes. There are just two points I would make on this. Based on my recollection of previous engagements and what we have heard from the Commission, the test of compliance around an excess charge ought to be reasonable. Therefore, it is a question of making a judgment on setting a threshold that could be considered reasonable in terms of a charge for excess consumption. A point was made on how that might change over time and on whether it would be reviewed in time. Water usage is dependent on water-saving devices and what the norms are. The norms now may be entirely different than they were ten or 20 years ago. The questions of reasonableness and changes over time might be considered as part of a test.