Shown in the image is the Pollards constructing a trench to install a new scour valve at Morton Dam, in the early to mid-1990s. Around the same time, the Morton Dam Strainer Building was decommissioned. Scour valves are situated at low points or between sections of the pipeline with valves. They serve to enable occasional purging of the lines to eliminate sediment and to facilitate draining the line for maintenance and repair purposes.
Photographer: Lance Harrison.