We’re nearly ready to remove the first section of concrete facing! Stockpiling of materials has commenced in readiness for constructing the first section of filter buttress and the team completed a successful trial placement of sand, gravel and rock layers against a practice embankment. This was a key step in further developing the construction methodology.

Edgar Toe Pond has been emptied. Pumping wells are progressively being installed along the causeway to lower the water table to the rock foundation, prior to excavation of toe pond material. This is critical to ensure the new outer wall is built on a strong and stable base. As part of this process, fish were removed and relocated, and the water emptied into sedimentation ponds. Once water quality criteria are met, this water will be released into Edgar Pond.

Offsite, Duggans, another great Tasmanian company, has been pre-casting 178 new concrete wave wall sections. Initially, these panels will be installed on the Lake Pedder side of the dam crest to protect the downstream work site from wind induced waves (currently such waves occasionally pass harmlessly over the concrete capped dam). Once the filter buttress has been built, the wave wall will be repositioned in its permanent location on the downstream edge of the dam crest, providing long term wave overtopping protection and a crest safety barrier.

Project team member alongside one of the reinforcing steel frames which is placed into a mould before having concrete cast around it. Once cured the mould can be removed and the pre-cast units transported to the dam site.

Drilling holes to install water table monitoring instruments