The Lockmaster

"A longboat plummets over the Great Falls, drowning the five passengers on board. The Lockmaster, the heir to an ancient title and responsible for guiding river traffic safely around this natural barrier on the White River, ought to have prevented this tragedy. His son is convinced that it was not an accident. Is his irascible father a murderer? A hydraulic engineer all too familiar with the brute force of rivers, he sets out to discover the truth and find his missing father."