Christchurch City Council is developing a long-term strategy for the management of wastewater in the Lyttelton Harbour Basin, especially 3 communities, i) Lyttelton ii) Governors Bay and iii) Diamond Harbour. Out of a long list of 9 options for treatment and disposal, and 3 were nominated by the to be carried forward.
Sustainable management of freshwater resources has become a focus of the planning process to ensure future development in many urban areas is possible in New Zealand. Where water resources are in, or predicted to be in short supply, a holistic approach towards water management is required to provide efficient water management, rather than tackling water use and management options in a fragmented way.
This paper will cover the issues considered with developing the strategy, such as challenges with high quality water recovery and efficiency of design.
A number of municipal wastewater treatment plants in New Zealand operate simple sludge digesters with floating roofs, biogas recirculation mixing, low volatile solids (VS) loads (about 1.5 kg VS. m-3 digester.day-1), long hydraulic residence times (15-25 days) and low biogas productivities (0.7 m3 biogas. m-3 digester.day-1).
This paper details the design and construction, and assesses the performance of the pilot plant to date, in the context of the development of the Napier community’s wastewater scheme.
This paper will explore the reasons why things have changed and has it helped, or has it made life more difficult. HSNO and OSH who is it and what is it, why do we need it and what has it changed?
This presentation discusses the results from using ozone and ultra-filtration membranes to remove manganese from water. However the presentation will mainly show how looking for treatment equipment in China can be interesting and rewarding.
New technologies have given the engineer additional tools with which to analyse the complexities of wastewater systems. This paper discusses the importance of the hydraulic model and the advantages it brings in wastewater system planning.
The New Zealand National Rivers Water Quality Network (NRWQN) has been running for 2 decades. The network consists of 44 sites in the North Island and 33 in the South Island (all located near flow recording stations) at which 14 physical and chemical variables are measured monthly.
Over time, well yield can reduce, water quality alter and operational costs increase, however with appropriate well maintenance these problems can be remediated or avoided altogether. Well maintenance comprises activities undertaken to allow a well to continue to operate at maximum efficiency, thereby prolonging well life.
Wastewater treatment can either be energy intensive, or provide an energy resour ce. A small shift in the selection of treatment technologies can significantly affect the energy profile of the NZ wastewater sector.
Flow cytometry is an effective tool for the study of algal ecology, physiology and toxicology. It allows for multi-parameter analysis of individual cells on the basis of light scattering properties, indicating cellular complexity, and fluorescence.
This paper describes the methodology of a model developed in Matlab which integrates hydrology with irrigation demand and supply, and allows the interaction between these different components to occur within the model simulation.
This paper presents a case study of the project, focusing on the management tools used and the links to other water supply initiatives within Metrowater and the Auckland region. It demonstrates an integrated approach to water supply planning.
Mosgiel's bores-sourced water supply has high levels of free carbon dioxide which is corrosive to metallic plumbing. Formerly treated by limited aeration and caustic soda dosing, alternatives to the caustic soda dosing were considered following three unrelated overdosing incidents.
This paper demonstrates that the installation of rainwater tanks for supplementary water supply is not a cost effective proposition and offers no benefits to the size of the water treatment plant and water supply network. Economic and environmental benefits may be achieved in delaying future water sources if the current water source is stored water (dam, lake, aquifer, etc.).
This study investigates the application of a structured optimization process involving preliminary investigations, appropriate instrumentation, testing, and dynamic simulation software for the reduction of electricity usage and alum dosing at full scale nutrient removal plants.
Our aim was to determine whether human-pathogenic viruses are present in surface water used as the source of drinking-water. We regularly sampled two rivers over two years. Enteric viruses were concentrated using ultrafiltration and detected using PCR for adenovirus, norovirus, enterovirus, rotavirus, and hep atitis E virus (HEV).
This paper describes the treatment process used at the Luggage Point AWTP to produce high quality water capable of meeting the Australian Drinking Water Quality (AWDG) guidelines.
Nelson City has a population of approximately 44,000 people with a limited commercial and industrial base. Councils Trade Waste Bylaw was made operative in 2007 establishing two methods for Trade Waste charging.
Operations, ConservatiA dry summer on the Kapiti Coast can give staff interesting challenges to keep demand at a level that is within our consent limits. With the completion of a supplementary bore field in 2005 the control measures have become less restrictive, but have also presented some new unforeseen consumer problems.
This paper describes development work on a new portable sluice-valve flow meter that enables a conventional sluice-valve to be converted into a temporary metering point.
This joint paper outlines PDP’s involvement in advising CCC with regard to hydrogeological matters relating to compliance with DWSNZ, including development of an advanced hydrogeologic model and the methodologies involved.