I have been confronted with this question many times without much scriptural or moral justification but observed that such practice seems universal.

Please assist with verifiable reason(s) why such happens.

interesting question!

Na so we meet am, na tradition. Give unto Caesar what belongs to Caesar.

What I learnt according to we Yoruba's believe is to avoid such occurrence again in the family or town so that is why the dead body is buried by the river where it get drowned

I think it is beyond that. Let's do a little research further.

cornoil:
Na so we meet am, na tradition. Give unto Caesar what belongs to Caesar.

AfroMighty:
What I learnt according to we Yoruba's believe is to avoid such occurrence again in the family or town so that is why the dead body is buried by the river where it get drowned

I would rather we see beyond Yoruba's.. as someone already Posited that it's about prevention of regular flood which I don't see any logic in that.

Do remember that this practice is the standard globally.

Where are the elders of the land