Drowning

Anyone have any good advice for drowning or custom moves?

Saving Throw doesn't seem to work very well, so I used Defy Danger which is obvious, but on a failure drowning immediately seemed weird.

So, I had them take damage. Which also seemed weird. Perhaps I should have followed up with impending doom, like, "You start to feel your lungs fill with water..." and, then had them roll another Defy Danger? I don't know.

Just looking for general advice / ideas / custom moves. I foresee more swimming occurring and I'd like to be better prepared. :)

This was an AW custom move that was in effect for a game I played in.

When you find yourself in the water, roll+sharp.
If you are in unfamiliar waters, take -1 to the roll; if you cannot take a moment to survey the water, take another -1 to the roll.  On 10+, you get wet.  On 7-9, choose one of the following:
-You are noticed by a shark or sharks.
-You are noticed by something else.
-You find a particularly nasty bit of effluvium.  Take -1ongoing until you can get clean.
-You run into something sharp.  Take 1-harm, and you are now bleeding.
(by MC Charlton Wilbur)

This move is obviously based on spotting threats in hazard-filled water, so WIS would be the analogous stat.  If the move were based solely on keeping your head above water STR would be more appropriate.

Derived from the Choker:

When you're in danger of drowning, you have a number of chances to find safety equal to your level. When you try to swim to safety, roll+Con.
On a 10+, you’ve found a safe place to breathe.
On a 7-9, you take 6 damage and gain +1 Ongoing to find safety.
If you run out of chances to escape, you pass out and will drown.

I think drowning best fits as a custom move and these are great candidates. How drowning works depends a lot on the situation, I think all the solutions suggested so far (including just covering it with GM moves) would work.

Another way to handle it with a GM move: tell them the requirements and ask. "You've plunged under water, your armor's dragging you down. You've got a second to lose some weight or you'll be at the mercy of the mermen for rescue. What do you do?"

I'm sure a lot of custom moves could be generated depending on the situation.  Seems like:
Swimming or keeping your head above water - STR
Avoiding obstacles in the water - DEX
Holding your breath - CON
Recalling how to escape the submerged ship - INT
Spotting dangers - WIS
Being attractive enough, even sopping wet, to be rescued by mermaids - Priceless

I really like the choker version and Sage's GM moves.

@mease19: I have this custom move in play:

When the situation warrants, roll Defy Danger using a different stat. The GM will tell you which one, based on the situation.

Great advice everyone! Thanks!

Another way to handle it with a GM move: tell them the requirements and ask. "You've plunged under water, your armor's dragging you down. You've got a second to lose some weight or you'll be at the mercy of the mermen for rescue. What do you do?"

As Always, Sage hits the nail squarely on the head! Cut and paste immediately into my 'handy DM hard move quotes' on the inside of my DM screen (yes I have a DW DM screen).
Awesome :)