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Part Vl—Summary of Recommendations. (Paragraphs 67-71.) Constitution and Boundaries of the Metropolitan District. (Paragraph 67.) : Sewerage and Sewage Treatment and Disposal Schemes. (Paragraph 68.) Utilization of Sewage and Other Wastes. (Paragraph 69.) Drainage of the North Shore. (Paragraph 70.) Disposal of Trade Wastes. (Paragraph 71.) PART I—INTRODUCTION 10. The planning of an adequate drainage system for the City of Auckland and the adjacent districts presents certain special problems due to a large extent to topographical features and also to certain other factors such as the very large population increase that has taken place in the area and its distribution. There are two large catchment areas having a natural drainage to the Waitemata and Manukau Harbours respectively, and there are also certain smaller areas the drainage of which is to the waters of the Hauraki Gulf situated outside the limits of the former harbour. The two harbours differ materially in certain important respects. The Waitemata Harbour is a deep-water harbour which accommodates ships of all sizes and deals with a very large volume of shipping, both overseas and coastal. It is also used as a terminus for an extensive overseas seaplane traffic. Its waters, and those of the Hauraki Gulf, are used extensively for yachting and boating and there are many popular bathing beaches and seaside holiday resorts in the harbour and gulf. The Manukau Harbour, on the other hand, has shallow waters with large areas of mud-banks at low tide, making it suitable for smaller ships only. Its waters and shores are much less used for recreational purposes than those of the Waitemata Harbour. Further, the factories and works of various industrial concerns such as fertilizer, meat, and tannery undertakings are situated on or near the shores of the harbour. It is reasonable to expect that the future development of the district and growth of its population will be considerable and that by the year 2000 the population will amount to 600,000 people. It is, however, difficult, if not impossible, to determinewith any confidence in what parts of the district the development will take place or how the population will be ultimately distributed. 11. Although the necessity for comprehensive drainage planning was recognized as long ago as the year 1878, it was not until the early years of this century that any positive action was taken. Action was then taken at the instance of the Auckland 1 Harbour Board, which had become concerned about the practice of discharging crude sewage into' the Waitemata Harbour. It is interesting to observe that although at first the problem was regarded as one affecting only the City of Auckland, before very long it came to be appreciated that the rapid increase in population of the metropolitan area necessitated the consideration of .a scheme, for a wider district. Accordingly, in the year 1908 the Auckland City Council arranged for a well-known London drainageexpert, Mr. G. Midgley Taylor, to visit Auckland and make an investigation, and proposals made by him for a comprehensive drainage scheme tfor the metropolitan area were adopted. Briefly, the scheme provided for a system of intercepting sewers and an outfall at Orakei with screening before discharge. As the districts of several local, authorities were affected it was necessary for the constitution of a new administrative authority, comprising representatives from the local authorities, to be empowered by statute, and this was effected by the Auckland and Suburban Drainage Act, 1908, which also gave power for the execution and operation of the required works. 12. The construction of the first part of the scheme was completed and put into operation in the year 1914, and subsequently the remainder o'f the scheme was carried out. By the year 1927, however, or even earlier, it became apparent that the scheme was not adequate for the requirements of the district, and the Auckland Harbour Board requested the Drainage Board to take action in order to extend the Orakei outfall sewer

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