Nearly two million more Brits will be under a hosepipe ban from tonight as the country's record-breaking drought continues and a sixth heatwave was forecast.South West Water has announced restrictions on hosepipe use for all customers across Devon, Cornwall, parts of Dorset and Somerset and the Isles of Scilly.The company, which supplies 1.8million customers, said prolonged dry weather and high demand were placing 'increasing pressure on the region's water resources'.The official ban will come into force at 0.01am tonight, but homeowners were 'asked to begin following the restrictions immediately to help protect water supplies'.Restrictions mean customers are legally banned from using hosepipes for watering gardens, washing cars, patios and boats, or filling swimming and paddling pools.South West Water also asked businesses, homeowners and visitors to the region to ensure they 'use water wisely by taking shorter showers, turning off taps while brushing teeth and only running washing machines and dishwashers with full loads'.But the utility company - which insisted it had been 'working around the clock to maintain reliable water supplies for customers across the region' - did confirm that water can 'still be used as normal for drinking, flushing toilets, washing and cooking'.Eight other water companies – Affinity Water, Anglian Water, Cambridge Water, Dŵr Cymru Welsh Water, Essex and Suffolk Water, Southern Water, South East Water, and Thames Water - have already brought in bans, affecting about 25million customers.Parts of the UK have endured an exceptionally dry and hot spring and summer, with a drought declared last month for all of Wales and more than half of England – covering parts of the south-east including London, West Midlands and all of the south-west.But today, the Environment Agency (EA) said several further unspecified areas could be moved from 'dry weather' to drought status next week as public water supplies 'remain under increasing pressure with continued dry weather and high demand'.