Its not waterproof paper you're need, it's waterproof ink.
A while back I brought a cheapy all in one Epson ( it was cheaper than getting a new set of inks for the old printer!). It has pigment based inks rather than dye based. I tried it out when I found out, printed an A4 sheet off and stuck it under a running water tap, the paper fell apart before there was any evidence of ink run.
Ideal for those underwater survey outings :-)

So what happen to Menorca? Seems a bit waterlogged at the moment!

I think the lack of mapping in this area maybe due to too much Sun, Sand & Sex :-)