Thanks for your advice Gary, but thankfully it wasn't too difficult to sort out..... Underneath where the windscreen meets the bonnet there is a long channel which was absolutely filled with rain water. The two drain holes were blocked with leaves and gunk. This water was then finding another way to escape, ie into the footwell! These drain holes can in future be reached from under the bonnet: two rubber outlets which protrude down. I could easily squeeze out the gunk and all the water flushed through. A serious design flaw by Ford - I hope this helps anyone else with my problem.
I have a 2014 Ka and have recently noticed water leaking in to the drivers footwell, usually onto my foot when I press the clutch! It smells like water, not washer fluid etc. It has been raining heavily recently, but it doesn't leak all the time - just one 'gush' after the car has been parked for a while and I drive off. Any suggestions to how to stop this please? Really didn't expect it to leak after two years after previously owning a beautiful fault-free 1996 Escort for 16 years! Thank you very much.