Abstract
Many irrigation tanks need their rehabilitation urgently, because they are centuries-old. This paper is associated with excess leakage of impounded water through an earthen embankment. An attempt to identify leaky embankment transactions using the result of field investigation, to decide the rehabilitation method and to estimate the permeability of the improved embankment is made for an overage tank in Ehime prefecture, Japan.
There seems to be a highly permeable layer between F.W.L. and W.L.-5.0m in the embankment judging from the in-situ up-to-date data and the hydro-geological data. And, the identification enabled the small scale improvement work, namely, the embankment of 10.0m depth from the crown was excavated and replaced by the impermeable soil. Further, the electrical resistivity surveying was carried out and the validity of the rehabilitation work was demonstrated by comparing between the results of the improved zone and the original zone.
