Mount Crosby Low Level Treatment Works

The Mount Crosby low-level treatment plant was constructed as part of the Mount Crosby Waterworks project. The work was undertaken in stages, with the aerator, sedimentation basin (later converted to a flocculation chamber) and laboratory completed in 1917. Built on a ridge directly below the high level waterworks, the work required considerable earthworks and foundations, leaving no room for filters which were constructed a kilometre away at Holt’s Hill. The low-level treatment plant was subsequently expanded to include an additional flocculation chamber, flash mixer, rapid filters, sludge handling plant and central control room which are major components of the expanding technology of the waterworks. The additions called for an unusually compact layout at the site. The treatment plant, in conjunction with Holt’s Hill, represents the beginnings of large-scale attempts to provide Brisbane with purified water.