In Over Her Head: Book 1 Part 1 of Re-evolution: Eaglefall

Used - In a distant future where humans now share the planet with their evolutionary cousins—goblins, dwarves, and winged men—a young woman is rescued. Unsure of who she is or how she ended up unconscious in a savage wilderness, she takes up a sword when all hands are needed and proves herself in battle. At least she doesn't die. Gaining new friends who admire her bold spirit, Lori is sent to Riverton, the capital city, in hopes she'll find opportunity. Instead, she is wrapped up in the turmoil of criminal and political corruption that appears to go all the way to the royal family. The local mafia has the city's business locked down and, in the case of the harbor which has been closed to the tides for over a decade, it is literally stagnating. Polluted water is choking off trade and the lives of those who live on the coast and in the nearby waters. Lori gains employment with the city's preeminent scientist, the flighty Dr. Walker, earning the respect and friendship of city officials. Her budding, out-of-control magic powers also get her involved with the clerics at the city temple. She finds spell casting a confusing and often painful exercise, nowhere near as easy or safe as experienced mages make it look. Desperate to help her boss protect his business and save the city, Lori embarks upon an expedition to find relics for a vital project, but it doesn't take long for her to realize she may have been a wee bit overconfident when she set off alone into the wilderness. In the ruins of an ancient city, where she runs into giant rodents, an old friend, and brutal barbarians, she's pulled deeper into the web of treason and betrayal threatening the people of Eaglefall, a wrong she'd love to help right, but first she must survive and make it home to Riverton. And are those merfolk?