Rob Westcott (in the May edition of WEM) claims that our 'stressed' water resources demand compulsory metering. But what effect does reducing water use actually have?

Water abstractions have to be licensed, and all new licences (since 1965) have conditions, such as hands-off flows, to minimise their impact. If demand is to increase in a stressed area, the water will have to come from where, when and how it can be sustainably abstracted. There is no shortage of options, as our winter resources far exceed our needs. Of course new developments (probably reservoirs) cost big money, but so does demand management and we need the best balance between the two.

The financial side of that balance is relatively straightforward, but what of the environmental side?

Domestic water use consumes almost no water, and leakage none at all - they just borrow it from one place and time and return it to another. When returns are inland they augment river flows and enhance any downstream abstraction. Even coastal discharges offer the option of deliberate reuse.
And every leak is water returning to the environment - unplanned and haphazard for sure (just like rainfall), but beneficial, especially in the desiccated summers predicted by global warming.

So properly-licensed abstractions for domestic use cause minimal damage, and the subsequent returns are almost pure gain. The net effect is to move winter water to summer, making the environment wetter, not drier, when it matters. (The much-publicised cases where the opposite happens are historic abstractions which for legal reasons could not be properly licensed).

It may seem paradoxical, but given proper licensing, both domestic use and leakage normally lead to environmental gain. In the economic case for increasing supply, as opposed to restricting demand, the environmental component is likely to be a resounding plus.

The need for compulsory meters, or for excessive zeal over leakage, is far from clear.

David Evans FCIWEM