[bigeasy1]

Yep they're scuppers as mentioned.
I love, love, love, my 23" Seacraft Tsunami,(it's an I/O)but I hate those scuppers.
I'm not familiar with the 20's but I would move as much weight as possible forward of the stern.A pair of plain old drain plugs is invaluable when you want to make sure water stays out.

I unfortunately have a kicker motor that weighs 110 lbs,along with four down riggers with another 60lbs of weight on them located at the stern.
That along with the weight of the I/O package being heavier than an outboard,and an engine box, bilge & transom that I overbuilt makes the boat very stern heavy.
This renders the scuppers useless when one guys in the corner fighting a fish,especially in the spring,when the water temp is in the high thirties to mid forties.

As soon as everybody is seated again,or when at the dock they work fine.
I've tried the Vortex method and sometimes they work great and other times they don't.
I lay in bed at night thinking of ways to make a fool proof anti water intrusion do jiggy.