Library

The use of GRP pipe in water and wastewater systems

04/08/2010

This paper covers the history, design, longevity and installation of GRP pipes in water and wastewater networks.

The South Australian approach to rural township community wastewater management

04/08/2010

This paper includes a brief discussion of funding models for construction and maintenance of a CWMS. The viability of inclusion of stormwater capture and re-use infrastructure as part of a CWMS is discussed in three examples.

Managing underground services in a trenchless installation project

04/08/2010

This paper will discuss the best practices to be followed, as well as a risk management strategy, for both the Contractor & Principal with regard to the issue of locating & managing underground services. It will consider how both parties’ legal & contractual obligations can be met, investigate the latest technology available to assist in locating services and also discuss the unseen risks associated with drainage laterals.

Reinjection of construction dewatering water at the University of Canterbury

04/08/2010

This paper discusses the investigations and the reinjection system, and illustrates the effectiveness of this solution through groundwater level monitoring data collected during construction.

Recognition of specialist skills for horizontal directional drilling

04/08/2010

This paper will discuss the benefits of the nationally-recognised qualification and the role the water industry needs to play to achieve them.

Effects of composting process on microbial indicators

04/08/2010

Keeping waters apart - New separation distance guidelines for onsite wastewater systems and wells

04/08/2010

This paper briefly describes the guidelines, outlining the approach taken to the modelling and its limitations, and explains the use of the Guidelines.

Managing a key resource using advanced water asset management

04/08/2010

This paper is based on interviews with New Zealand water suppliers on pipe renewals and replacements decision processes. The research suggests that many of the larger water suppliers believe they have management practices in hand and that the smaller water suppliers have budgets too small to contemplate proactive replacements. In the middle are water suppliers that want more integrated, interactive asset management systems,great er certainty around remaining pipe life, and a better understanding of the effect of maintenance and replacements on network-level performance. These water suppliers also indicate they would welcome more guidance from the industry.

Creating greater project value through constructability

04/08/2010

This paper presents guidelines for effective constructability and provides examples where constructability has enhanced project outcomes.

De-silting the Helensville raw water dam

04/08/2010

This paper outlines the method used and details the risk and environmental impact minimisation deployed by Downers during this sustainable project.

Challenges of small town water supply upgrades: The Reefton experience

04/08/2010

Aurecon was engaged by the Buller District Council to upgrade the drinking water supply for the township of Reefton, after it failed to meet the Drinking Water Standards New Zealand (DWSNZ), as required by the Health (Drinking Water) Amendment Act 2007 by 2014.

Success with pressure sewerage scheme at Grovetown

04/08/2010

Grovetown is a community of approximately 300 people situated in flat and low lying land 5 km north east of Blenheim. The area suffers from difficult ground conditions including poor drainage and a high water table, conditions which had led to the failure of many of the household septic tanks. Several options were considered for upgrading Grovetown’s on-site wastewater systems and incorporating conveyance of effluent from the nearby Spring Creek oxidation pond. Marlborough District Council decided to install a pressurised sewer system using grinder pump systems on each individual property, and a common pressure main from Spring Creek to the existing Blenheim Sewage Treatment Plant (STP).

Huapai wastewater network: Renewal of a gravity wastewater network with a pressure waste collection system

04/08/2010

The township of Huapai, northwest of Auckland in Rodney District, has had an existing gravity wastewater system replaced with a Pressure Waste Collection (PWC) system. This paper considers the driving factors in the selection of PWC as a solution for Huapai, making it the first gravity wastewater network replaced with a PWC system in New Zealand.

Priorisation of wastewater pump station upgrades using asset management practice

04/08/2010

This paper describes how we worked with CCC’s existing asset data, combined with expertise in PStn design and engineering, to devise a strategic prioritisation programme of PStn upgrades for input to the 2009-19 Long Term Council Community Plan (LTCCP).

Colour formation in pulp and paper wastewater treatment systems

04/08/2010

Pulp and paper wastewaters are coloured, and further colour can be formed during biological treatment. Colour discharge increases the attenuation of sunlight, thus affecting the ecology and aesthetics of the receiving water. The higher reported colour formation in activated sludge systems (AS) compared to aerated lagoons (AL) was studied.

Anaerobic biodegradability of wood: A preliminary review

04/08/2010

The literature shows that wood is relatively non-biodegradable in anaerobic environments, though there is a wide variety of results ranging from <2% to 40% of stoichiometric conversion, or roughly <1% to 20% of wood carbon converted to methane carbon. This contrasts with IPCC assumptions that 50% of wood will degrade in landfill environments.

Key microbial groups of MBBR systems at Wellington's sewage treatment plants

04/08/2010

Moving Bed Biofilm Reactor (MBBR) systems are used in more than 400 wastewater treatment plants (WWTP) worldwide but little is known about the microbial communities on which these systems rely. This study aimed to address this issue by characterizing the microbial community composition at Wellington’s Moa Point (MP) and Western WWTPs.

Use of floating wetlands to treat nutrient enriched lake water

04/08/2010

The nutrient attenuation performance of floating treatment wetlands (FTWs) planted with emergent wetland macrophytes was investigated in 4 one-week long batch mesocosm studies using artificial eutrophic lake water. The FTWs were made from buoyant polyester mats (0.6 x 0.6 m squares) planted with one of three native wetland species, Cyperus ustulatus, Juncus edgariae or Schoenoplectus tabernaemontanii.

Artificial aeration of Auckland's lakes

04/08/2010

Through effective management of source waters, suppliers can improve raw water quality thereby reducing the overall cost of treatment and, ultimately, the cost to the consumer.

Nutrient conditions influence size distribution and settling properties of activated sludge flocs

04/08/2010

The study aimed to investigate the relationship between activated sludge (AS) particle (floc) size distribution and nutrient conditions in different bioreactor configurations. Size distribution profiles of fl ocs that formed in continuous (B1), continuous with clarifier and return sludge (B2) and SBR (B3) reactors were investigated in parallel under identical nutrient conditions. An eight-fold dilution of the influent COD of a synthetic dairy processing wastewater resulted in a “feast and fast” regime that triggered significant effects on the biomass and flocculation characteristics. Floc size analysis of reactor MLSS revealed a shift in floc sizes when reactors were fed with the mi nimum COD wastewater feed (0.61 g L-1 ).

Same goal, different approach; Comparing DVGW & USEPA UV drinking water regulations

04/08/2010

This presentation outlines the approach taken by these two agencies and details the key similarities and differences. Presenting also comparative data from validations undertaken on the same UV system with each approach. It shows example sizing and the consequential capital and operational costs differences between the two approaches.

The use of acoustic dopp;er profiling in wastewater networks

04/08/2010

Our findings indicate that although further development of ADP wastewater monitoring systems is required, the enhanced flow data accuracy means that this technology is the future of flow monitoring.

A simple, pragmatic approach to preventative maintenance of pump stations

04/08/2010

This paper reviews both parts of the project which necessitated a generic and pragmatic approach appropriate to the asset be used.

Low energy MBR systems - implication for New Zealand wastewater design

04/08/2010

This paper reviews the design of MemPulse and operating plants with particular relevance to the NZ market.

The water and wastewater knowledge management system, developed by operators for operators

04/08/2010

This paper outlines how Hunter Water Australia (HWA) developed a knowledge management system (KMS), a ‘one stop shop’ where all aspects of plant operation are fully integrated and accessible in a timely manner. The benefits being how the KMS has improved training, operational consistency and has provided an extension of the quality management system to field operations.