cutoff wall
диафрагма
A wall of impervious material usually of concrete, asphaltic concrete, or steel sheet piling constructed in the foundation and abutments to reduce seepage beneath and next to the dam.
Source Guidelines on Instrumentation on Large dams by Central Water Commission Ministry of Water Resources, River Development & Ganga Rejuvenation Government of India, June 2017, p.72diaphragm wall
диафрагма
A cutoff wall of flexible concrete constructed in a trench cut through an embankment or the foundation.
Source Guidelines on Instrumentation on Large dams by Central Water Commission Ministry of Water Resources, River Development & Ganga Rejuvenation Government of India, June 2017, p.72