You might be at the "Hail Mary" time. I'd try doing a Factory Reset (don't know what model you have, so I can't give the precise instructions, but you can search this site for them). Then try re-programming.
I'm sure you've given it more than a few moments to dry, such as a couple of days in front of a fan.
If worst comes to worst, you could look into sending it off to Uniden for repair. If they can't fix it, there may be a discount available for a comparable model.
https://repair.uniden.com/rates.cfm and
https://repair.uniden.com/repairInstruct.cfm
He's got the 325P2.
To do a reset on that scanner, and the unit turned off, press and
Hold Down the
Hold,
2, and 9 keys then press the power button to turn the scanner on. Don't release the Hold-2-&9 keys until the scanner starts to power on.
There may be a slim chance that your problem is water remaining in the scanner, more specifically the USB port (since you indicate it tries to turn on, but the memory is erased & your software cannot "see" the scanner). You might try leaving the scanner in a warm, dry, place, perhaps near a vent for your heating system, that stays warm due to air circulation. If you're lucky, if the rest of the water evaporates, it may try to work. You could also try using a hair dryer to bathe it in warm air (keep the driver far enough away that air flow is only warm, not scorching hot). After allowing some additional drying time, then try the full reset & reprogramming.
If none of that works, then the scanner will need to go to Uniden for repair. Repair cost is a fl;at rate $79.95, with an additional $10 for return shipping, $89.95 total. (You pay the shipping
to Uniden, they handle the return, hence the $10 cost.)