Five damsites in the John Day Basin in southeastern Oregon were examined in the field as to their relative suitability. No exploratory trenching, drilling, or test pitting was carried on. The damsites are Canyon Creek, Fox Creek, Monument, Hall Hill, and Four Miles. They all lie in valleys carved in volcanic flows and tuffs. The main problems are strength of wall rock and foundations, location of undesirable tuff beds, leakage through cavernous lavas, faults, source of aggregate, and spillway problems.
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Prepared for the Division on Engineering Geology of the Geological Society of America, Engineering Case Histories 1 includes 9 case histories ranging from the geology of the Queens Midtown Tunnel to the McNary Dam, Oregon.