Is there such thing as a waterborne worm that enters penis?

Schistosomiasis: Is probably closesest condition to your question. Has a very complex life cycle & is worm-like in one of its developmental forms. Occurs primarily in africa, but also asia & s.America. Water snails are an intermediary host, present in streams, rivers (eg nile) or lakes. They are parasites which enter via skin then travel to liver via lungs then other organs & classically cause bladder cancer.