What was the condition of the water? Calm and clear? Muddy? A ragging turrent? Dreaming of water in general tends to represent aspects dealing with emotions.
Large bodies (like an ocean) indicate your overall emotional self. The river is like a channel for your emotions, perhaps as a means bywhich you express them. The river might also be more like a drain and it is sapping you of your energy. Or alternatively, it could be that you need to express more emotions and the flood is a representation of this. Generally floods can represent feeling overwhelmed, over stressed, unable to cope, it can also represent fears/anxieties (those kinda go hand in hand). Other possibilities - depression, or prolonged saddness and fraustration from saddness.
The boats are like vehicals we use to explore bodies of water, or - emotions. They represent the self and its ability to subdue the waters. Thus over turned boats probably mean being in a situation you don't know how to handle or cope with. The boats might not be about "emotions" persay, but rather a situation(s) in your life that might make you feel like you are being overwhelmed, as though you were in a flood.
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