I did not realise that the Ross Fountain was the extra on blip this day last year and also on the 18th when it was covered in ice.  This afternoon there was no water, yet it is seldom turned off.  Sensors detect if there are problems with the pumps not working or there is a lack of water power so they can be turned off by remote control. The sensors also detect daylight levels to switch on the lighting. So perhaps there was a problem.