JG Afrika undertook the geotechnical investigation for the raising and rehabilitation of Nacala Dam by an additional 4 m.
The 17 m high by 300 m long earth embankment dam had been overtopped on two occasions and was leaking through the embankment.
We analysed the existing structure, providing proposals for remediation and undertook the design for raising the dam, including stability and seepage analysis.
JG Afrika reviewed the original geotechncial data before its construction in 1968.
We planned and programmed the borehole drilling through the existing embankment, in addition to undertaking the DPSH, piezocone and Lugeon testing into the bedrock.
In addition, JG Afrika investigated and identified construction material sources and drilled for spillway positions and designed the specifications and monitoring programme.