This simple and relatively cheap measure would use a wasted resource and reduce water charges. It would reduce the amount of rainwater going directly into foul drainage, a major cause of untreated discharge of sewage into rivers and the sea. My system used recycled containers and cost about £150.
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This measure could contribute to the national effort to combat climate change & could eventually have a small effect on flood reduction.
If extended, perhaps by Government grants, to include existing properties, the benefits to climate change & flood reduction could be very worthwhile.