The first 30 years of Lefkara Dam

Abstract

The 74 m high Lefkara embankment dam was built in the early 1970s for the Republic of Cyprus Water Development Department in order to supply domestic water to the cities of Famagusta and Larnaca. It is a rockfill dam with a central clay core composed of a combination of residual soils and colluvium supported by diabase rockfill shoulders. The dam was well instrumented using total pressure cells, piezometers and internal settlement gauges as well as surface settlement markers. These instruments are still working and the results are discussed in the paper. The dam is curved in plan since it was anticipated at the time of its design that the arched plan would help resist the thrust from the reservoir, but in reality it made virtually no difference to the behaviour that would be expected from a straight dam. Instead of the conventional vertical valve shaft for housing the water intakes at various levels, a semi-buried inclined gallery (shaft) has been adopted. Leakages of reservoir water through the gallery joints into the gallery have been creating problems at high reservoir levels. The embankment and its foundation proved to be quite watertight and the seepages recorded are remarkably low.