Thune Dam is situated near Boponong, Botswana in the Thune river valley and is a 35m high Mass Concrete (CFC), Clay Core Rock Fill Dam with a crest level of 1600m. Structures includes a mass concrete overflow spillway with a 11 million litre/day capacity water treatment works and some 101km of water supply pipelines, storage and pump-stations.

Instrumentation installed includes piezometer to measure pore pressure, settlement cells to measure total settlement and total load cells to measure the load against the retaining wall. CR 1000 Data logger with multiplexer to read and record all the piezometers and pressure cells.

Thune Dam Instrumentation consists of the following:

• Vibrating Wire Pressure cells around and the CFC Clay Core retaining wall measuring total load and pressure.
• Vibrating Wire Piezometers in the Clay Core of the coffer wall/embankment, measuring pore pressure.
• Vibrating Wire Settlement Cells in the rock-fill for measuring settlement.
• Data Acquisition System CR800/1000.

Instruments installed in and around the Dam Embankment are intended to monitor:

• Pore Pressure in main embankment;
• Settlement of main embankment;
• Total load against the retaining wall.

Installed Instruments Specification:

Piezometers (Clay Core)

• ITMSOIL Vibrating Wire Model W9

Settlement Cells (Clay Core)

• ITMSOIL Vibrating Wire Settlement Cells

Pressure Cell (Clay Core/Retaining Wall)

• ITMSOIL Vibrating Wire Pressure Cells P6

Data Acquisition System CR800/1000 (Valve House)

• ITMSOIL Data Logger CR1000

Designers: Arcus Gibb

Consulting Engineers: Arcus Gibb

Contractors: Zhong Gan Engineering and Construction