ruthhope
Free Ranging
10 metres x 10 metres is perfectly adequate space for 3 or 4 ducks.Sadly you confirmed my thoughts. Ooof kinda gutted but I know it's not posssible. Thanks for the reply. Sadly I live in Aberdeen Scotland and space is limited.
Make sure it is predator proof -- foxes, owls and hawks would be a worry.
You can certainly use a kiddie pool.
Yes ducks will get water everywhere, but you can use deep litter in their duck house -- scoop out messy bedding, but just add more dry litter on top of wet areas. I use mainly pine shavings in my coop but when it gets very wet, I add a layer of dried leaves. You might collect leaves in the autumn and keep them for use in the coop. Perhaps getting the leaves dry will be an issue in the UK; I'm lucky as we have lots of hot sunny days for raking dry leaves in Florida!
Out in the run, leaves are also good for keeping mud at abeyance. My ducks free range and my garden is deep in leaf mulch and the ducks love it as they like rummaging for bugs in it. But I am on well drained sandy soil. If you are on clay, it will be more difficult to control mud. Some folks use artificial turf but I think that 3 or 4 ducks in 100 square metres won't be too bad