Cool story
When I was a kid I did this in the Mississippi
I did get a response with in a year, but cant remember the details
I'll bet it would be considered politically in correct now days, littering in all
I remember doing that in grade school when I lived in Arizona, only we used helium balloons instead of bottles. We stuck notes inside the balloons, then the teacher filled them with helium. We went outside and let them go, and one of the girls in class got a response back from a farmer, of all places, right here in Indiana, close to where I was born. We let them go at the start of the school year, and he found it that following spring when he was out getting his fields ready for planting.