The First Twenty by Jennifer Lavoie

Humanity was nearly wiped out when a series of global disasters struck, but pockets of survivors have managed to thrive and are starting to rebuild society. Peyton lives with others in what used to be a factory. When her adopted father is murdered by Scavengers, she is determined to bring justice to those who took him away from her. She didn’t count on meeting Nixie.

Nixie is one of the few people born with the ability to dowse for water with her body. In a world where safe water is hard to come by, she’s a valuable tool to her people. When she’s taken by Peyton, they’ll do anything to get her back. As the tension between the groups reaches critical max, Peyton is forced to make a decision: give up the girl she’s learned to love, or risk the lives of those she’s responsible for.