When the river is high, the force of the current carries the foam from the weir a long way downstream.
In the disastrous floods of 1998 all the houses you see on the opposite bank were flooded. Their gardens were inundated and the basement rooms filled with water, and some of the houses in the street had flood water in the ground floor too. The building on the extreme right of the row is the Post Office, and I saw the staff, two days after the flood, removing a lorry load of letters which looked like papier mache, which had to be separated and delivered if possible. The Church in the background stands on a slight hill. It was cut off by the flood water, and the crypt was filled to within six inches of the nave floor level.
There are pictures of the floods here.