Just my 2 cents experience
Got my wife an Arc 5 months ago. One day she dump the phone together with the cloths into washing machine(i do not know how she manage to do so Arc is not a small phone) Got a good wash and spin dry completely.
Then she found the phone! She tried to dry it together with the cloths under the sun but no dice in the end.
Call me evening at work and after some lecture from me i took the phone to my repair friend.
Well sony warranty will not work on this so full dismantlement for the Arc.
Some tissue wiping and hot air gun on the motherboard did the trick. Assembly back everything and the phone boot back to life
But the lcd is with water mark and the touch screen not working partly on the middle!So i took it back home,
got a tupperware filled it with some rice(uncooked) and kept the phone inside without the battery for a week.
After that the touch screen is normal and the water mark is gone. No need to flash or software repair. Simcard and sd working fine even after washing Been using the phone until now no problem.
It happen end of last year.Cos me RM10 to do it.(ok, it a members kaki price)

My two cents. U can try outside shop to repair it if your phone still can boot up.

This is not my first time. I drop my old Sony C510 in the sea water, then i took out the batt and went to the toilet and wash it with tap water

My repair friend open up the phone, clean with tissue,hot blow the phone and the phone came back to life.Well is was not 100% working, the back camera took 2 months to dry up b4 it decide to work properly. I have to change a new mike.

Its not that teruk as u think if u drop yr phone in the water, u stiil have chances to repair it.