The vent line for the gas tank is curled up on top of the gas tank so not very deep. Probably $25 or $30 to snorkel and extend vent lines and it's one of the easiest diy mods you can do.
Those that drown their machines fall into two categories, the one's with no mechanical knowledge and had no idea it was even possible (usually kids). Those that knew better and did it anyway (dumba**).
Either way, post event special maintenance isn't good. Drain the gas tank, pull the air filter, pull the plug, check the oil for water and change if necessary. Dry it out, new parts, fire it up.