Engineering can save us from drought Joseph Bazalgette, chief engineer of the Metropolitan Board of Works, was given all powers necessary by Parliament to modernise the sewer network. With one of my engineering heroes, Isambard Kingdom Brunel, his men constructed more than 1,000 miles of brick sewer under London's streets. It set a global gold standard. Today, two thirds of the world's run-off water is used to dilute and bear away sewage. Thanks to their foresight, this underground network remains with us. But now - quite rightly - there are plans to build a huge pipe the size of the channel tunnel, 35 meters below the Thames, to improve on the Victorian sewers. Civil engineers will answer the crucial question of how we move water that's stuck in the wrong parts of the country, and they are already overseeing the replacement of thousands of miles of leaking pipes to ensure it arrives where it is needed. But ingenious ideas from engineers will also help us use what we've got more efficiently. The statistics are staggering: the average Briton uses 150 litres of water a day. Reducing that amount is relatively easy. Lavatories use about 30 per cent of a household's water - 13 litres of water literally flushed away on an old lavvy, though much less on a newer dual-flush lavatory. But why are we using drinkable water in the first place? Couldn't we use our old shower water? Anthony Jakubiak, 24, from Milwaukee is doing just that. His invention takes water from your shower and reuses it to flush the lavatory. He has just been awarded a bursary by my Foundation to assist him in the development. And hopefully he will take it to market soon. But perhaps the more pressing demand is for the water you never knew you used. Industry uses vast quantities: it takes 11,000 litres to manufacture a single pair of jeans. And farmers are thirsty, too: it takes 20,000 litres of water to make a kilo of coffee - before you even boil the kettle. Almería province in Spain offers some insight into reducing demand from agriculture. It is the greenhouse capital of the world. 135 square miles of temperature- and humidity-controlled greenhouses, housing virile plants. Chemical fertilisers are drip-fed to each plant from vats nearby. They receive no more and no fewer nutrients than necessary. I'm not advocating a world where we are all drip-fed our nutrients, and wear shorts instead of jeans for fear of drought. Instead, I think it's time to resurrect our inventiveness. It's a simple adage but "doing more with less" leads to creative engineering. As with most problems, young minds often develop the best solutions. Each year my foundation runs the James Dyson Award, a student engineering competition that urges young people to develop problem-solving inventions. Last year's winner, Edward Linacre from Australia, took a very simple principle - condensation - and used it to strikingly good effect. By passing warm, humid, air through cool underground pipes, he was able to extract water using small amounts of energy, piping it directly to the roots of plants. Fewer spoilt crops. We've been hanging on to the coat-tails of great Victorian engineers for too long. We need to step up our vision and ensure we are equipped to meet our needs. It's for the government and water companies to take action on infrastructure, but here's a challenge to young, aspiring engineers: develop a device that saves water in the home. The simpler the better, and focus on doing more with less. Enter it into the James Dyson Award. And, better still, commercialise it to solve our drought problem. The James Dyson Award is open for entries until August 2: http://www.jamesdysonaward.org/