The bed on foundation of ISHII-DAM under constraction by Hyogo Prefecture, has the zone of high permeability (over 20 Lu) to water. The foundation treatment plan was basing the following. i) The purpose is exclusive flood control dam on reservoir operation. Therefore, the leakage from reservior can be allowed compared with dam where water level should be maintained for water supply. ii) The bedrock consists mostly of the granodiorite on the Cretaceous period of Mesozoic era, being firm. Therefore, the dam foundation is steady on underseepage for the long term. Afterwards, the ISHII-DAM construction work was completed. The test of filling began in November, 2004. The test of filling is being continued now. Because the quantity of leakage etc. have been monitored up to now, it reports to here.
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