I like these, Paddy. One suggestion would be to try a slower shutter speed to try to keep a bit of detail in the water. From my little knowledge of flowing water, teh trick is to keep teh water from looking like lead!
I like the composition of the last one most. The first has more potential – with teh bridge and the height oif teh drop – but maybe needs a different position for a better perspective.
I like your shots alot. Really enjoy doing these water shots always involves alot of practice. I agree with BM about allowing for a little more detail in the water or it might end up becoming too white. I think the second last photo is great but where the water meet the ground it is a little too what slightly overexposed but if you allow for a little more detail it would be great…