Now that we're really getting into the heat of summer, I can not get a clear answer as to whether or not swimming is halachacally permissible on shabbos. I can understand the prohibition of wringing a towel or one's hair, but what about standing in three feet on water? No getting hair wet ( and if I did, I would not wring it dry) no using a towel. Am I still prohibited. Can I submerge myself? After asking this question over and over - I still do not have a clear final decision or justification.
Any thoughts?

See 326 Mishna Brurah 21 and 24 that there is a Minhag not to “wash” your body with cold water (even though that Chazal only prohibited hot water. Even though the reason for the Minhag are because of squeezing hair and other reasons that you may get out of, but the Minhag works like a Lo Plug (no exceptions) since we don’t see anyone that makes such differences in the Poskim (at least of what I have seen.)

I heard that in Ohr Shraga (before my time), during a heat wave (in the days before air conditioners there), Rav Yaakov Kamenetsky permitted going to the pool (I guess he held under these dire circumstances it circumvents the Minhug. What would be an exact circumstance to permit I would defer to a Rav that knows the circumstance (since I don’t have a direct Kabalah.)) I heard that he only permitted it without swim trunks (maybe you’ll squeeze them) and without swimming (since it’s prohibited Midarabanan to swim on Shabbos.) On these conditions I have a Pikpuk (questions) on the Issur.

Though, of course we don’t permit someone to soak his clothing on Shabbos, only if he fell into the water, as per 301:45 MB 162. Or when he goes for a Mitzvah and needs to cross a body of water Ibid.4 and only when you wear it in a changed way (see there.) But that’s only for things that you don’t usually let it get wet, and you care about it being soaked, so we’re worried you’ll squeeze it. But bathing suits are made to get wet, so you don’t care if it gets wet, so we’re not worried you’ll squeeze it. This point is made in 320:15.

Swimming in a pool, once you get around the Minhag of not bathing in cold water, should be permitted, as of 339:2 since it has a rim to it (you don’t have it filled to the top) and is in a Rshus hayuchid. So Tzarich iyun on the prohibitions.

A towel is permitted, as per 301:48, as long as you don’t hand it to an attendant.

Rav Chaim, what about going into a mikveh instead of a "swimming pool"?

If it's cold, it's permitted as per MB 326:24, but hot Mikvah is Ussur (but Chasidishe do have their Heter for that too)

What is the heter? Is it used by all chassidim?

The Heter, as I understand it, that the only action that is ussur is R'chitza (bathing.) Toveling is a seperate action which is not included. The Talmidai Chachumim amoung them do not stay in the Mikvah, because that would be Rchitzah, but dip and go out right away. I don't know all Chasidim, but to my knowledge it's common practice.

G- swim! From your mouth to
G-d's ear.
Any problems, bring it on! Aru feeling lucky?
Jared ben David