In answer to your question, tape of the holes does not keep the area behind the seat dry. Or at least it didn't when I tried it. Looks like if should but...... Since I typically pack mine about 3/4 miles before suiting up and floating back downstream I bought a dry bag to store my street shoes, rain jacket, etc in. I also pack a small hand pump in case of a leak and to adjust according to temperature changes from 90+ deg. GA sunshine to 50- deg. river water.

I am glad you like it, I love mine.