This paper discusses: types, sources and loads of sediment and key physical and chemical contaminants in stormwater; and receiving environment status, impacts and recreational grading.
This paper presents the sampling methodology carried out, results obtained, and discusses the various chemical transformations that can occur as the product migrates through a stormwater network. The paper also discusses how Z and BP selected truck stops for DEF installation, and also the limited stormwater management options available in the current market to deal with the potential stormwater effects of this product.
This paper articulates the institutional processes, community understanding, technical guidance and functional delivery mechanisms required to support transition to water sensitivity.
The majority of New Zealanders live in urban environments, and national and regional community surveys have shown that improving the state of our urban waterways and environment are high priorities. Similarly, increasing the state of rural waterways has come under close scrutiny in recent times. In all cases, typically we select a single catchment or part of a catchment or watershed as the unit of management.
One benefit alliance projects provide is flexibility for major project delivery, and in doing so reframe the design context to better manage performance, cost and risk. Resource consent conditions can be too rigid, stifling this flexibility that is so important to getting the best out of an alliance procurement model. Consent conditions can be seen as risks to be managed which can often undermine the safeguards that they were intended to provide, even preventing opportunities for environmental betterment.
This paper discusses the development of the Forum, the lessons learnt and the success of adopting this collaborative approach to resolving stormwater management issues across a region.
After the flood events of 2013 Tauranga City Council embarked on a programme of 2D modelling and flood hazard mapping of the whole city. This was to enable Council to determine problem areas and inform the most cost effective way to mitigate them.
This paper presents several projects from the inception, through to the installation and follows up with the community as to the actual benefits of the project from a community perspective.
This paper looks in detail at the concept of resilience, and draws on related research to propose a framework for assessing and improving resilience to flood hazards. The framework divides resilience into a number of broad dimensions: namely community, technical and organisational, and develops a series of specific principles within each of these dimensions.
To work towards excellence in asset management, Auckland Transport is identifying future threats to its infrastructure assets from stormwater. This paper discusses the asset management planning, the results of studies and future preventative maintenance strategies.
This paper discusses the question: what is an appropriate Design Standard (Level of Service/Level of Protection) for primary and secondary stormwater systems in urban areas? Naturally the best answer varies for existing and developing areas across the country. Currently there is a lack of national guidance to support the definition of these levels and consequently there is a range of standards in use.
The Waterview Connection project for the NZ Transport Agency involves construction of 5 km of new motorway – half of it underground in tunnels – to connect the Southwestern and Northwestern motorways in Auckland.
This paper will outline how the first SMP in Auckland under the new PAUP was completed using a range of best practicable options to protect the receiving environment. Adopting a collaborative working model with the SWU was critically important helping immensely for Council and Client alike to navigate and interpret the new rules in the absence of final supporting technical guidance. The Scott Point SMP is a test case for the implementation of the PAUP to ensure the flow and new treatment targets are achieved for new greenfield development.
The paper will focus on the collaborative journey to develop technical guidance and policy, to forming alliances to facilitate and implement Blue Urbanism.
This paper outlines a number of stormwater fee structures that are based on impervious area and density of development. These models are considered to be more equitable than the current method of applying a general rate that makes no distinction between properties of similar value that have different demands on the stormwater network and different effects on the environment. Changing regulation has highlighted that there is more than one shade of green when it comes to charging for stormwater services.
In early 2014 Christchurch had the heaviest sequence of rainfall since the 1970s. Several large rainstorms fell in the city, saturating the ground, raising river and stream levels, and flooding homes, properties and streets. In many areas flooding was made worse by damage from the 2010-11 Canterbury earthquake sequence.
Soakage of stormwater is part of the natural water cycle that feeds groundwater and stream flows. In some parts of Auckland, soakage systems have been used for many years as a means of easily and cheaply disposing of stormwater close to source. Some of these systems have been ignored and poorly maintained leading to a gradual build-up of sediment and a reduction in performance over time. Areas suitable for soakage have not always been well defined and soakage has been attempted in areas outside suitable geology.
This paper describes refinements made to the life cycle costing model that allow users to compare the costs and benefits of conventional and WSD stormwater management for future catchment development scenarios. In this way users can determine whether beneficial net economic outcomes can be obtained from WSD stormwater management. The refinements integrate ‘real world’ costing data with findings from an international literature review which investigated cost comparisons between WSD and conventional stormwater management.
Resilience is a critical property of a liveable city. Urban communities aspire to live safe in the knowledge that life will go on ‘as normal’ in the face of extreme weather events or other natural disturbances. They also value high quality receiving environments that are not at risk of crossing ecological ‘tipping points’ as a result of the effects of the steady creep of urban development. Building resilience into stormwater management means adopting approaches that reduce vulnerability both to sudden natural shocks and to the potentially irreversible long-term environmental effects of urban development.
This paper presents a case study of a residential subdivision in Palmerston North where the independent quantification of secondary overland flowpaths by the author assisted in the resolution of a dispute (that was to be litigated in the High Court) about the effects of overland flowpaths paths on adjacent property.
This paper will focus on the authors’ recent experience during the development of a large subdivision in North Canterbury. During the planning and consenting phase of this development, an initial stormwater design which met the requirements of the subdivision was prepared and the system was later constructed.
The paper highlights the need for an integrated approach with other service providers including Parks, Auckland Transport, and Watercare and describes how Auckland Council (AC) utilises public-private partnerships to unlock growth in Auckland to ensure efficient delivery of stormwater infrastructure.
Keynote Address - This talk is based in part on Stormwater Paradigms, by Andy Reese published July-Aug 2001 Stormwater Magazine