Dams & Dam Spillways

RIX has proven experience to advise and assist in the design of spillway walls, using faster and cheaper shotcrete construction rather than traditional form and pour methods. Erection of formwork in limited access areas, use of cranes, bracing of one-sided form work, pouring pressures, stripping of formwork, increased labour and reduced productivity all result in high costs and extended programs. Shotcrete will remove the need for formwork and reduce the labour.


In order to reduce program length and cost, RIX worked with LEIGHTON and the Department of Commerce to gain approval for shotcrete as an alternative to conventional form and pour concrete to the walls in the Spillway section of the dam. Upon completion of pre-construction testing, approval for the shotcrete wall design was given and RIX installed all reinforcement and 3,500m2 of finished shotcrete, up to 1m thick in some areas.

As staged excavation on the approach roads to the dam and to the spillway floor level (up to 50m deep) preceded, geotechnical design required that large areas required permanent support. Around 4,000 rock bolts were installed with 7,000m2 of mesh reinforced shotcrete stabilisation.

Centre: 14m high, 1m thick spillway walls at Hinze Dam in Queensland. RIX assisted in design, planning and construction of the curved and finished panel section shotcrete walls.

Left: Shannon Creek Dam – shows the bottom spillway at Shannon Creek Dam under shotcrete construction.

Right: Shannon Creek Dam – Shows the spillway mid-fall section completed.