In Troubled Waters, Paul F. Paskoff offers a comprehensive examination of the federal government's river improvements program, which aimed to reduce hazards to navigation on the great rivers of America's interior during the early and mid-nineteenth century. Danger on the rivers came in a variety of forms. Shoals, rapids, ice, rocks, sandbars, and uprooted trees and submerged steamboat wrecks lodged in river beds were the most common perils and accounted...