New Plymouth Waste Water Treatment Plant; David Lean
New Plymouth city has long been sewered, the central city being reticulated in 1903. Wastes from the city were discharged into the Tasman Sea through an ocean outfall off Eliot Street within the city precinct. Before discharge the sewage was held for some hours in ‘liquefying tunnels’ designed to retain grease and other floating material and to remove a certain amount of settleable organic solids. Because if the unacceptability of this discharge in 1974 the City of New Plymouth, later joined by the Taranaki County Council, commissioned a study of the disposal of wastewater of the city and adjoining areas. After a number of amendments to the original 1974 proposal the New Plymouth Waste Water Treatment Plant was opened in November 1984. The plant takes raw sewage and trade wastes from New Plymouth City, Bell Block and Inglewood. It uses a biological treatment process known as activated sludge aeration to produce a high quality effluent. The clean effluent is discharged to the Tasman Sea via a 480m ocean outfall. The quality of the water leaving the plant is one of the cleanest in New Zealand and well within the New Zealand standard for safe swimming and seafood gathering.
The collection includes notes, publications and reports compiled by David Lean relating to the issues raised regarding the New Plymouth Waste Water Treatment Plant. Also included are newspaper clippings and correspondence.
- Two Waste Water Disposal Schemes for New Plymouth Incorporating Land Based Treatment Plants. Prepared for the City of New Plymouth by The Taranaki Green Sea Action Group, Ken Holyoake and Trevor John, September 1980.
- A Study of the Effect of the Proposed New Plymouth Ocean Outfall. Prepared for The Taranaki Green Sea Action Group, Kerry Wood, 1979.
- The New Plymouth Wastewater Treatment Plant, New Plymouth District Council, 1990.
- New Plymouth Carrousel Plant, presented to New Zealand Water Supply and Disposal Association, John R Fitzmaurice, August 1984.
- Newspaper supplement. What is Watsewater? Published by The Joint Wastewater Committee of the New Plymouth City Council and the Taranaki County Council, April 1980.
- Speech notes. David Lean, opening of the New Plymouth Waste Water Treatment Plant.
- Invitation, opening New Plymouth Waste Water Treatment Plant, 2pm 17 November 1984.
- Information brochure, New Plymouth Waste Water Treatment Plant.
- Study of Wind Effect on the Raw Sewage Discharge, Len Hannan.
- ‘The Technical Society and Public Confidence’, by Dr E A Hasen for The Taranaki Clean Sea Action Group, March 1981.
- Photocopied Newspaper clipping. ‘Sewerage Saga’, Daily News 3 October 1984.
- New Plymouth City Council, Trade Wastes Bylaws, Steven Fitzmaurice and Partners (Consulting Civil and Public Health Engineers), 5 April 1983.
- Rough notes by David Lean.