Unlike Brian I assume your reference to "raw water" systems is the same as the USA meaning a raw water cooled engine/exhaust. If you also meant your potable drinking water I would agree with Brian and say no. Just use cheap Vodka for that.
As for your raw water cooled engine for me it would be a simple choice between ruining your exhaust system and maybe your engine or possibly killing a few small sea critters - easy choice. The town or factory up the road is probably putting more crap than that in the water every minute
Windshield wiper stuff may not be the best but it will probably work. I've had my washers freeze up at below zero but not burst and work fine when warmed up a bit.