Near Iron, Minnesota, waters split along a three-way divide, carrying minerals and contaminants to Hudson Bay, the Great Lakes, and the Gulf of Mexico. Susan B. Ellingson (SB to those who know her) runs a small paper with the help of her best friend and a part-time staff. When a mining company seeks a permit to dig for copper and nickel and store potentially harmful mining waste nearby, SB commits to covering the story.

It isn't easy. She wrestles with financial stress and personal pain. Her dead wife lingers in spirit. Their children have grown and left home, and SB's Labrador provides sweet but insufficient company.

Her mother-in-law leads a group of Ojibwe and Métis grandmothers fighting to protect the water, and after an intriguing new woman comes to town, SB isn't sure how to feel or act. After a fiery environmentalist informs her that a local water scientist has gone missing, she follows a trail of evidence from a tiny, off-grid community into a global tangle of lies, corruption, whistleblowing, and danger.