Sink Trap (Georgiana Neverall Series #1) in Bloomington, MN

Former corporate drone Georgiana Neverall loves her new occupation as a plumber's apprentice, but is a bit surprised when she finds the favorite brooch of Martha Tepper, the town's former librarian, clogging a sink. Georgiana has a sinking feeling that Martha may have been retired permanently-and suddenly it's up to a plumber's apprentice to flush out a killer.