Because he didnt bath there, falling on water would remove loose dirt but without scrubbing and/or running water dirt sticking to your skin(scales in this case) won't wash off, and well, about the smell, most of the time you will still stink even if you scrub under running water, if it has been long enough the stench sticks to you and to fight it off you will have to use some sort of hygiene product (like soap).
Why did I write a through explanation on how bathing works...? Thats weird