Long Ashton new developments

Where I wonder does any developer in this area expect to provide water services to any new development from?  Has anyone had a good look at Chew Valley Lake recently. It has not to my knowledge been so low even I believe in 1976 when we had no rain from April to the end of August. Why is it so low? The water company is now supplying Bristol with water from the Mendip Hills. This is leading to a shortagefet stringly by the sailing club who are having difficulties with their bigger dinghies having enough water to sail and race successfully. If as has been put forward that 9,500 houses should be built on Fenswood Farm and between the proposed new ring road, shelved for the moment but.... where exactly do the authorities that might approve this plan propose water to service it comes from?