North shore main sewer drainage system, Auckland

The North Shore main sewer drainage scheme, at Auckland, is at present under construction and provides for a single central treatment plant with oxidation ponds and an outfall in the Hauraki Gulf. In the paper the basis of the design of the scheme is given together with some details of the construction including trunk sewers, tunnelling, pumping stations, oxidation ponds, and outfall. Costs of the work completed and under construction are given as well as the estimated costs to complete the scheme and the anticipated works programme. No attempt has been made to include details of all phases of the scheme, the emphasis having been placed more on a general description with some design details included.