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4  Hand level & rod, binoculars, probe (old ski pole)  100’ tape, 25’ tape, 6’ folding rule, measuring wheel  Flashlight and/or mirror  Bucket and timer (to measure seepage rate)  Stakes, flagging, poke stick  Aerial photo of inspection area  Rubber boots, snake chaps, sunscreen, insect repellant, Bear Spray, First Aid Kit, sensible clothing for weather  Drinking water, food  Rubber hammer  Outlet inspection camera and sled, a Do-It- Yourself (DIY) camera and sled was included in a previous article titled, You Con-du-it; How to Fix a Leaky Pipe  Confined space entry equipment and paperwork  An experienced yet open and creative mindset Assemble Documentation – Documentation may include a map or drawings of the dam and the inspection form. Below is a list of some other documentation that may be useful:  List of potential failure modes  Previous inspection checklists  Old construction photos  Plots of instrumentation data  List of previous repairs or modifications and repair recommendations  The dam’s electronic project file (if available), loaded on a tablet for reference, if needed  Talk to last year’s inspector about problems or issues and document. General Inspection Guidance The purpose of an inspection is to observe every part of a dam and its appurtenant structures to identify changes between inspections. Performing inspections by the same person, during the same time of year under the same type of reservoir loading has advantages and disadvantages. For example, it is important to inspect a dam when the reservoir is at a similar level as the previous inspection to confirm observed seepage is similar to previous inspections. However, there are also advantages to inspecting the dam during different seasons with different people and during different reservoir levels. A late season inspection often provides the inspector the opportunity to see the upstream face of the dam…a good opportunity to look for sinkholes, as described below. If the dam has piezometers, arrangements should be made to measure the static water level during the inspection (preferably at full pool). The inspector(s) may need to have a bit of flexibility in their schedule(s) to see how the dam responds to varying or similar conditions. Terminology – Make sure to use accurate dam terminology. It’s better to use upstream and downstream, left and right – typically facing downstream, instead of using compass directions. Providing clear definitions for good, fair, and poor condition is also important for future inspectors to understand how the condition was assigned. Use the SIMPLE Rule – For documenting defects, Sketch the location of the defect, Measure the defect (depth, width, length), Photograph the defect, Locate the defect in reference to a known location (use existing stationing or measure from a known feature like the outlet works or spillway). Photo Tips – Consistency: Take photos at the same location and orientation as previous photos. Using a scale in the photos helps document size and/or extent of the feature being documented. Photos can be used for comparison if conditions change. Zigzag vs. Parallel – These are two methods primarily used to inspect a dam: zigzag or parallel (Figure 1). Typically, the zigzag method can be used on small dams by inspectors who are physically fit. The parallel method is useful for steep or rocky slopes. For both methods, it is important to make sure that the inspector stops periodically and turns 360˚ to observe the slopes near and far for anything unusual before continuing on the inspection. Teamwork – If inspecting with two people, develop a system so that one person is taking photos and keeping the photo log and the other person is measuring and documenting observed conditions. The person with the gym membership can be the one to hike up and down the slopes while the other walks along the crest.