Purpose: This manual describes the inspection, evaluation, and repair of hydraulic steel structures, including preinspection identification of critical locations (such as fracture critical members and various connections) that require close examination. Nondestructive testing techniques that may be used during periodic inspections or detailed structural inspections are discussed. Guidance is provided on material testing to determine the chemistry, strength, ductility, hardness, and toughness of the base and weld metal. Analyses methods that can be used to determine structure safety, safe inspection intervals, and expected remaining life of the structure with given operational demands are presented. Finally, considerations for various types of repair are discussed.