Spring Grove Dam

Type: Roller Compacted Concrete (RCC)
Construction Date: February 2011 - August 2013
Location: Rosetta KwaZulu Natal, South Africa
S 29.318883° E 29.965575°
Spring Grove Dam, situated in the Mgeni Water System in KwaZulu-Natal, South Africa is a Roller Compacted Concrete Dam (RCC), with a 607m crest length. The structure includes a free crest spillway with a crest length of 70m over RCC. The dam structure futures a rock-fill clay-core coffer wall/embankment stretching 325m.

Spring Grove Dam was constructed by Group 5 Pandev Joint Venture and has an active storage capacity of 139.5 million m³.

Spring Grove Dam Instrumentation consists of the following:
  • Vibrating Wire Embedment Strain Gauges in the RCC measuring strain.
  • Vibrating Wire Long Base Strain/Jointmeters measuring over induced joints.
  • Vibrating Wire Thermometers measuring temperature.
  • Thermistors measuring temperature.
  • Six Vibrating Wire Rod Extensometers (inclined and horizontal) measuring zone movement and tilt.
  • Vibrating Wire Foundation Piezometers for measuring pore pressure.
  • 28 individual 3-D Mechanical Crackmeters measuring three-dimensional movement on the crest.
  • Vibrating Wire Transducer measuring seepage.

Instruments installed in and around the Dam Embankment are intended to monitor:
  • Tilt of the Dam;
  • Measuring movement over the induced joints;
  • Stresses and strain of the concrete;
  • Total downstream seepage;
  • Pore pressure build-up in foundation;
  • Lake level water height.

Installed Instruments Specification:
V-Notch Weir (Dam, Outlet works)
Soils Vibrating Wire Transducers Vented Model 4580
Piezometers (Clay Core and RCC Dam Wall)
Soils Vibrating Wire Model W9-50-SST
Joint Meters (Rcc Joints center spillway)
Soils Vibrating Wire Model ST-JI-4-1000
Strain Gages (Centre Rcc Wall and flanks)
Soils Vibrating Wire Model ST4-S250-3-1
Standpipes (Manual measuring holes downstream from dam)
• Geotechnical Instrumentation Casagrande Standpipes
Rod Extensometers (Spillway)
ITMsoil Vibrating Wire Transducers Model E7-1.1-6
Thermometers/Thermistors(Up to Downstream in Rcc)
Soils Vibrating Wire T3-1.1/TM1-75
3 D Crack meters Manual
• Geotechnical Instrumentation 3D Crackmeter with Dial Gauge
Data Acquisition System CR800/1000 (Valve House)
ITMSOIL Data Logger CR1000

Designers: BKS

Consulting Engineers: BKS

Contractors: Group 5 and Pandev Spring Grove Joint Venture

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