Until 2008 Western Bay of Plenty District Council’s modelling data had been collected through a third party professional service provider. The intent of all stormwater, wastewater and water models was to provide input to respective Asset Management Plans. The main goal of those models was to identify undersized parts of the reticulation in need of upgrading. None of them, with the exception of the water model, were intended to be kept up to date and/or used to optimise system operation.
In this paper we will examine how long term monitoring significantly changed the model calibration and outlook on how the system performs. We will use the Whangarei sewer catchment as our case study which highlights dramatic seasonal differences in dry weather base flow and consequently inflow and infiltration estimates. These seasonal flow differences were unseen with the short term flow monitoring effort and this paper highlights the risk of using only a short snapshot of monitoring data to project long term trends and develop long term options.
The September 2010 and February 2011 Canterbury earthquakes had a devastating effect on the city of Christchurch and a significant impact on the City’s water and wastewater infrastructure. Opus International Consultants were engaged by Christchurch City Council to assess the impact the loss of water supply infrastructure would have on the Central City Water Supply Zone supplying peak summer demand.
This paper describes how Public Private Partnerships (PPPs) w ork, compares a BOOT project in the Middle East w ith a Design Build Operate (DBO) project and a Design and Build (D&B) type project, both in New Zealand, details risk allocation and cash flow , and explains w hy the bankers love investing in infrastructure. It also identifies and describes multiple project delivery methods, from traditional services to divestiture.
This paper looks at real case studies from all three locations to understand what happened to water and wastewater infrastructure during these natural disasters and how managers coped with the various challenges that arose. Comparisons are made between the case studies with the intent of providing delegates who are responsible for water and wastewater infrastructure management some perspectives on what may constitute good risk management and response practice.
This paper compares and contrasts the theory behind the chlorination exercise with the practicalities of implementing a chlorination strategy.
Emergency Planning and Recovery, Freeboard, natural hazards, flood risk, easements, local government, building code, NZA related topic of setting acceptable freeboards for floor levels adjacent to flood areas is also explored considering the Building Code and New Zealand Standard 4404:2010 documents both offer an arbitrary 0.5m freeboard for habitable floors. An alternative approach based on modeling the hazard as represented by the catchment area, depth and speed of flow is presented. The paper will benefit local government representatives and be of interest to a wide spectrum of the industry.S4404:2010
The paper also describes the implementation of a number of initiatives to minimise capital and operating costs, minimise environmental effects whilst maintaining a robust solution for a community with widely fluctuating population.
Acid Mine Drainage (AMD), a result of historical and current coal mining, and the associated oxidation of pyrite within the coal measures, is a significant environmental liability for Stockton Opencast Mine, located on the West Coast of the South Island, New Zealand. This liability is likely to persist for at least 100 years. With up to 6,000 mm of rainfall per year, often in intensive events (some up to 100 mm/hr), water management is critical for the control of adverse effects that include low pH, dissolved metals (including aluminium), and high suspended solids in drainage waterways. Traditionally, neutralisation of AMD at Stockton coal mine has been carried out by direct dosing of ultra-fine limestone (UFL) to affected waterways.
The geothermal drilling process makes extensive use of drill cuttings ponds for the storage and disposal of drilling fluids and drill cuttings. Generally the local practise is to discharge the drilling fluid to the pond and rely on soakage for the ultimate disposal of the water content.
This paper explores approaches to data collection on the repair work to the underground pipe networks in Christchurch following the earthquakes. In particular, it will showcase a software application used to capture closed circuit television (CCTV) inspection data. CCTV based data is facilitating the post-disaster repair, design and management of Christchurch’s underground pipe network.
Condition Assessment, ChristchThis paper explores how Christchurch is embarking on rebuilding the w astewater and stormw ater infrastructure, and the integral role that thorough data assessment, using GIS and InfoNet is playing in this strategy to ensure that multiple data sources are reviewed, risk profiled and then prioritised to meet the requirements of the Stronger Christchurch Infrastructure Rebuild Team, insurance companies and the future asset management processes of Christchurch City Council.urch, earthquake, wastewater, stormwater, pipes, GIS, Infonet, CCTV
Wastewater Issues, Pressure sewer, difficult terrain, energy efficiency, progressive cavity pumps, innovative design solutions
Wastewater Issues, Waste stabilisation pond, FTM technology, water quality, receiving water, better disinfection, nutrient attenuation, sustainable
Buried pipelines often operate in a state of anonymity with respect to internal or external corrosion. A condition assessment project allows a condition profile of the pipe to be developed through an examination and/or evaluation of the external and internal environment using various technology applications. External environments provide the typical culprits that promote water pipe corrosion and condition assessments provide useful information to determine pipe condition for renewal or monitoring decisions and future asset planning.
On the 4th September 2010 Canterbury was rocked by a massive 7.1 magnitude earthquake that started a sequence of earthquakes in the region that still continue. Due to the underlying estuarine soils, the coastal town of Kaiapoi, along with two neighbouring settlements, was affected by very severe liquefaction and lateral spread, with approximately one third of the town’s water and roading infrastructure made inoperable and over 1,200 homes damaged; many uninhabitable.
Wastewater Issues, Wastewater, Hastings, tangata whenua, biological trickling filter, no sludge, innovation, paradigm shift