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2 Dam Safety Inspections… A Closer Look Introduction Safety inspections are an important and necessary responsibility of dam owners. The goal of a safety inspection is to identify potential dam safety deficiencies before they become dam safety incidents. If not corrected, these deficiencies can turn into serious, costly repairs or even dam failures. Dam inspections are also a great opportunity to gather the owners, engineers, experts, regulators and all stakeholders involved with a dam in order to educate, communicate, to delegate responsibilities, to discuss possible failure modes, to plan for emergencies, and to establish long term relationships concerning the dam. This article is intended to be a high level overview of the safety inspection process for small low-hazard dams from planning to implementation. For additional details regarding dam safety inspections, the reader is encouraged to visit the Association of State Dam Safety Officials (ASDSO) website and view the webinar titled, Introduction to Inspecting Dam for Owners and Operators. Why are Inspections Important? During an inspection of an emergency spillway, an inspector identified open, unsealed joints between concrete spillway slabs (Photo 1). Photo 1: Concrete spillway from the inspection report. Photo inset shows an open joint. The openings were as wide as 1 inch and had vegetation growing in them. A recommendation was made in the inspection report to repair the joints, but the dam owner neglected to implement the repair. Four years later the spillway operated and the water flowed into the open, unsealed joints causing uplift pressures to develop beneath the slab that ultimately led to the failure of the spillway slabs (Photo 2). It cost the owner more than $1.25 million to reconstruct the spillway. The spillway failure may have been averted if the owner had implemented the repairs recommended in the inspection report. The cost to implement the inspector’s recommendation was estimated to be approximately $500. Photo 2: Failed concrete spillway following operation during a storm event. Types of Inspections Typically dam safety organizations and dam owners will conduct a variety of inspections including formal, intermediate, routine, and emergency inspections. Regulatory requirements, hazard classification, dam condition, and special events dictate the scope and frequency of dam inspections. A qualified engineer is required for formal, intermediate, and emergency inspections. Due to safety concerns, some inspection activities may need to be performed as a team or with the aid of specialized equipment. For example, inspections of the conduit may require confined space entry protocols or a remote operated vehicle (ROV). A detailed discussion about conduit inspections was presented in a previous article titled, You Con-du-it; How to Fix a Leaky Pipe. Who can be an inspector? People who have:  Good knowledge of the design, operation, maintenance, and potential failure modes of the dam.  The physical capability to