I am delighted Antony Oliver has got excited over his new water butt (NCE 1 September 2005). But I wonder if his excitement has overwhelmed his critical thinking.
He says Thames Water would confirm that 'every little helps'. But by his own account, this butt is for plants that didn't previously get watered. So there's no water-saving here. This is additional water use, all lost as evapotranspiration.
And it's a real loss, unlike his water 'normally thrown away'. Why do so many people believe the world ends at their outlet pipes?
Even ignoring downstream abstractors, there are wetlands, streams, and rivers downstream, with real environmental water needs. If this butt is used for irrigation, it will be refilled from summer rainfall after dry spells, precisely when those watercourses most need the flow.
Sorry Antony, but if you really care for the environment, you should cancel the butt now, and plant your garden with deeper rooting shrubs.
Dr Keith Weatherhead (M), Institute of Water & Environment, Cranfield University, Silsoe, Bedford MK45 4DT