What Causes Blocked Middle Ear Post Ear Infection?

I have blocked middle ear after an infection which has failed to improve significantly despite many months of decongestant & steroid spray treatments. Next step suggested has been insertion of grommets. I am a 66 yr old male and am concerned that as I sail & race dinghies most weekends in the spring summer & autumn it will prove difficult to avoid immersion in water from time to time when I fall out or capsize. Should I agree to grommets to sort out the problem, or is it likely to give me other problems of infections or ear pain?