The ANCOLD WA YPG’s first event of 2016 was held on the 18th February 2016 and was a site visit to Samson Brook Dam where remedial works are currently in progress. The dam is located around 100 km South East of Perth near the town of Waroona. Samson Brook Dam is a 31 m high earthfill/rockfill dam with a puddle clay core and was constructed between 1938 and 1941. Samson Brook Dam is classified as a High A consequence dam in accordance with ANCOLD Guidelines.
Remedial works have been conducted in three stages at Samson Brook Dam. The first stage was outlet works which involved replacement of the upstream intake structure, sleeving of the existing outlet pipes and installation of two new guard valves. The second stage was embankment remedial works including reconstructing the downstream rockfill section of the dam and installing a filter system with a rockfill weighting zone. The third and final stage, which is currently under construction is a spillway upgrade. This upgrade involves decommissioning the existing glory hole spillway and constructing a new spillway with a design capacity of 280 cumecs on the right abutment.
SRG are the contractor for the stage three works. SRG mobilised to site in November 2015 and are due to be complete by June 2016. Work has been progressing well with excavation completed for the spillway chute, approach and batters. Filters and cut-offs have been installed for the chute and some sections of the spillway floor and walls have been poured.
Recently there was a large bushfire in the area which devastated the town of Yarloop and caused work to stop on site for 2 weeks. The entire workforce was evacuated prior to the arrival of the fire. Interestingly given the consumption of all the vegetation by the fire, most of the construction plant and offices were not damaged by the fire.
Our thanks go to all those who attended and most importantly to Eddie Anastazjew (Quality Assurance Assessor, Water Corporation) for showing us around the site and Bob Wark (Technical Director Dams, GHD & ANCOLD WA State Rep) and Jason Fowler (Job Manager, GHD) for providing information regarding the design.
ANCOLD is an incorporated voluntary association of organisations and individual professionals with an interest in dams in Australia.
