Thursday 22 April 2021 Ngoc Minh Ngo On the sun-drenched island of Crete in the south of the Mediterranen lie stone remnants of the first great civilisation of Europe: the Minoans. Within the rubble is evidence of flat rooftops with attached drains and cisterns; open courtyards feeding into sediments tanks; and rills and gullies ribboning through the grounds. It's evidence of the ancient practice of harvesting rainwater. In the garden we are just as beholden to the water gods as the Minoans, but unlike them, we don’t use only what falls from the sky, but what flows from the tap. Conservative estimates put the average UK household's tap water use in the garden alone at approximately 10,000 litres of tap water every year. Even if you halved this to 5,000 litres, that’s still a lot of water.