In a blistering third year of drought, Californians have been asked to limit their indoor water usage to 55 gallons (208 litres) per person per day. It takes about 30 gallons to fill a bathtub, so forget about a deep Jacuzzi experience. Yet in the gated communities of Calabasas and Hidden Hills – exclusive enclaves in the Santa Monica Mountains above Malibu – lush lawns and filled swimming pools and koi ponds make it clear that some are ignoring the rules. So officials have created a device to take power showers away from rich and famous water hogs. A small metal disc with a pinhole drilled through the middle, it has seriously reduced the flow of water into some multimillion dollar homes. People here call Derek Krauss the ‘water police’.