Ducks are the opposite of chickens. The girls make all the noise. I am sure some are more vocal than others, but in my flock, there was the same amount of quacking when I had 2 girls as there is now they just seem to take turns but the overall quack level is the same. The exception is my Pekin who is supposed to be a girl quacks as raspy as my drakes, but twice as loud as any other of my girls and three times as often (as a duckling she peeped twice as loud too). They are too young for me to have actual experience, but my runners and Welsh Harlequin (best laying breeds) are the more vocal of the bunch. Might be just mine or might be the breeds.
Duck + anything + water = mess! If you can isolate it so there is Duck + water and Duck + anything else, mess will be reduced but ducks will try to put everything in their water and water on everything. As an example, I have two pools right now for my flock. A stock tank and a kiddie pool. To get to the stock tank, they have to walk a six foot long ramp (about 3 feet up). That water only has poop and feathers in it and the surrounding area is left alone. The kiddie pool has a couple brick steps, but they can reach in and drink from it anywhere around its perimeter. The pool is full of mud constantly and they have dug an 8" deep hole on one side of it (about 8 x 4" wide). They splash the pool water in the hole, make more mud and dig deeper, putting the mud in the pool. A potential solution would be to put gravel or pavers around the pool to "block" immediate access to the dirt and let the water soak through but that can cause it's own problems. My solution will be to build a second ramp and use another stock tank. I agree that a single duck will probably be lonely at night when the chickens roost. They are very social, so I would at least consider a pair (meaning two, probably not a drake in your situation).
