Excess Fluid

If your composter does get overloaded with fluid, you'll probably notice a river-bottom odor coming from the bin.
Don't despair.
Remove the soil and worms and undigested scraps, perhaps in small amounts in plastic supermarket bags.
Clean out the bin or pails, and reintroduce the soil and worms mixture gradually by the trowel-load.
This will give the soil some aeration and drainage properties it had lost.
If you have a chance to add some strong fibrous material, such as straw, so much the better.
If the soil is very wet, some dry shredded newspaper will help even out the load.