The dam spillway crest and chute were built between 1969 and 1972 from reinforced concrete.
An inspection of the dam in 2015 recorded an increasing level of seepage through the joints in the spillway chute concrete slabs.
After an investigation was performed, it was revealed that the transverse drainage underneath the chute floor had suffered varying degrees of damage and was blocked in places. Varying degrees of corrosion were also found in the ground anchors.
The works were confined to the 10:1, 2:1 slopes of the spillway chute, dissipating areas and included reinforced concrete continuously poured forming an overlay slab over the existing concrete spillway surface.
Fortec was engaged by Sunwater to undertake drilling, grouting and installing of anchors as part of the Fairbairn Dam Spillway Improvement Project.
