"The Secret Tunnel" by Joy Nelkin Wieder

The king of Ashur plans to lay siege to Jerusalem, intending to take the city by blocking off the Jews’ water supply. Eleven-year-old Yonatan’s father, one of the best quarrymen in the city, is drafted in to resist the king and Yonatan is desperate to help. The Jewish men hatch a plan to divert the fresh water via a new tunnel so that they and not their enemies will have access to it. The family’s preparations for Pesach coincide with the enemy army’s planned siege. The enemies are struck down by a plague before they can attack. A Tunnel Facts section explains the true story behind the book