Watermain is starting to make sense...
http://maps.google.co.uk/maps?q=hounslow&oe=utf-8&client=firefox-a&ie=UTF8&hq=&hnear=Hounslow,+Greater+London,+United+Kingdom&gl=uk&ei=5R_6TPX1HoqWhQe7nYjpCg&oi=geocode_result&ved=0CB0Q8gEwAA&t=h&ll=51.514582,-0.359405&spn=0.001679,0.004823&z=18
I've...