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Research Report 285 Aquatic ecotoxicity of cutback bitumen

Published: | Category: Environmental impacts of land transport , Research programme , Research & reports | Audience: General

Most chipsealing in New Zealand is carried out using bitumen cutback (i. e. diluted) with kerosene. Under the new regulatory framework established by the Hazardous Substances and New Organisms (HSNO) Act (1996), bitumen with the addition of kerosene between 2. 5–20% by weight has been classified as a 9. 1C substance that is ‘ecotoxic to the aquatic environment’. Other (non-ecotoxicity related) classifications also apply. Cutback bitumens with more than 20% kerosene are not classified. The 9. 1C ecotoxicity classification is derived from a calculation based on the aquatic toxicity of kerosene. Implicit in this classification is the assumption that the kerosene in cutback bitumen has the same bioavailability as pure kerosene. The object of this research was to establish whether this assumption is valid and whether the 9. 1C classification for cutback bitumens is warranted.

Research Report 121 Validation of LEQ model for road noise assessment in New Zealand

Published: | Category: Environmental impacts of land transport , Research programme , Research & reports | Audience: General

An evaluation of models which predict noise levels from road traffic in terms of the LEQ (24-hour) index was undertaken in 1998 by comparing predicted levels with noise levels measured at 20 sites. These sites included motorways, highways, urban arterials and urban streets in New Zealand. Three main LEQ models were evaluated: the Nordic, the FHWA, and the CETUR models. In addition, the CRTN model was included as a LEQ -type model with both UK and New Zealand road surface corrections, and a simplified version of CETUR. The Nordic model was able to correctly predict noise levels within ±2 dBA at all 20 sites. CRTN was able to predict LEQ (24 hour) to the same level of accuracy as L10 (18 hour), and predicted 15 sites. The CETUR and FHWA models were less successful, with only 65% correct predictions.

Research Report 318 Clay mineralogy of modified marginal aggregates

Published: | Category: Environmental impacts of land transport , Research programme , Research & reports | Audience: General

This study, undertaken in 2003–2004, aimed to:

study changes produced when additives are mixed with roading aggregates containing swelling clay minerals;
identify the most suitable chemical to use for a particular rock type and the quantity required to achieve particular effects, namely:

conversion of the clay to a better form,
establishment of bonds between particles,
strength that is insensitive to water content,
minimal drying shrinkage
permanence. Samples of fresh, partly weathered and weathered rocks of three rock types were taken from four quarries. Cement, lime or Durabind was added to the partly weathered samples at two levels. The untreated and treated samples were analysed. Proctor Needle and CBR testing was performed on the partly weathered samples. Volcanic rocks contained a higher proportion of more readily weathered minerals than greywacke. Drury greywacke was more intensively sheared than Otaika greywacke.

Research Report 446 The variability of road traffic noise and implications for compliance with the noise conditions of roading designations

Published: | Category: Environmental impacts of land transport , Research programme , Research & reports | Audience: General

Many road designations have conditions with respect to noise that require that when the road is completed, measurements will be undertaken to prove that the performance standards of those conditions have been fulfilled. However all measurements are subject to variability, and the designation conditions do not address either the expected nature of this variability, or how it should be accounted for in establishing compliance with the conditions. This research was carried out in New Zealand between 2006 and 2008. It sought to quantify the variability in noise measurement, and then in light of this identified variability, develop a recommended approach to establishing compliance. This report first discusses the evolution of current practice, and then examines in detail the expected variability that can occur both in noise generation and noise propagation.

Research Report 513 Impact of urban form on transport and economic outcomes

Published: | Category: Environmental impacts of land transport , Research programme , Research & reports | Audience: General

Urban form describes the physical shape and settlement/land use patterns of cities and towns. This research addressed two key questions: 1) How urban form impacts on transport and economic outcomes and 2) How regional and local council planning policies can contribute to a more efficient and durable urban form. We found that urban form has modest impacts on transport outcomes, through reductions in vehicle ownership and drive mode share. On the other hand, urban form was found to have relatively large impacts on economic outcomes, primarily by virtue of its impacts on agglomeration economies. Several promising areas of further research have been identified that would seek to strengthen and deepen our understanding of the linkages between urban form, transport, and economic outcomes.

Research Report 515 - The effect of rainfall and contaminants on road pavement skid resistance

Published: | Category: Environmental impacts of land transport , Research programme , Research & reports | Audiences: Communities, General

This research project, which was undertaken between 2003 and 2006, aimed to improve the understanding of the effect that environmental factors (eg rainfall and detritus) have on the variation of measured skid resistance, both in the short and longer term. Phase 1 of the research was a field study of seven sites in the Auckland and Northland regions over 2. 5+ years, with regular skid resistance measurements primarily utilising the GripTester. Phase 2 involved developing a new laboratory-based accelerated polishing device and methodology for testing large (600 x 600mm) chipseal surfaces with the Dynamic Friction Tester. Phase 1 results demonstrated that significant and previously unpredictable variations (greater than 30%) in measured skid resistance could occur over short time periods. These variations were the result of a number of interrelated factors, including the geological properties of the aggregates and the contaminants themselves.

Research Report 019 Land transport externalities

Published: | Category: Environmental impacts of land transport , Research programme , Research & reports | Audience: General

The report provides a literature review and research plan describing where further research is needed to quantify or value external effects, otherwise known as externalities, from the land transport system. It examines the efficiency and effectiveness of economic and regulatory instruments and mechanisms for internalising transport-related costs. The report examines how the prnciples of sustainable management apply to the land transport system under the Resource Management Act 1991. The project was broken down into four main tasks and include 1. a preliminary identification of external effects, 2. a comprehensive literature review of actual and proposed approaches used to quantify or value externalities and the types of non-market instruments and mechanisms that are being used in New Zealand, 3. an assessment of legal duties and statutory constraints relevant to valuing, pricing or regulating externalities and 4.

Research Report 190 Traffic noise guidelines for low noise areas

Published: | Category: Environmental impacts of land transport , Research programme , Research & reports | Audience: General

A study, carried out in 1998–2000, investigated if a traffic noise lvel of 55dBA, the level allowed in the 1994 Transit New Zealand Road traffic noise guidelines, was an acceptable limit in New Zealand for areas that previously had low traffic noise. A case study approach was used for four roads, two of which had been open for about two years, and two had been open for about 12 years. A sample of residents were surveyed for their attitudes to road traffic noise in comparison to the general amenity of the area. The study also determined if the road traffic noise resulted in lower prices for those houses more exposed to road traffic noise but found that no effect could be isolated from other factors which might also influence price.

Research Report 625 Use of technology to measure and improve freight movements

Published: | Category: Environmental impacts of land transport , Publication Category , Research programme , Presentations , Research & reports

The advance of technology has created several rich sources of data to analyse road network performance and freight patterns. New technology is also driving intelligent transport systems (ITS) designed to improve transport operations. This research used Auckland as a case study to explore how existing and real-time data sources could be used to manage network performance and improve journey predictability for urban freight using ITS solutions. Drawing on previous research and a wide range of international literature and case studies, the report presents an overview of the role of ITS and the innovative ways technology is being applied to measure congestion and manage infrastructure more effectively. Extensive industry stakeholder engagement revealed a high level of frustration and urgency to find solutions to improve network efficiency and an acknowledgement of the role of technology alongside infrastructure and regulatory measures to support efficient urban freight movement.

Research Report 116 Lead-based paint management on roading structures: Section IV – Model specification

Published: | Category: Environmental impacts of land transport , Research programme , Research & reports | Audience: General

This report is Section IV of four 'stand alone' documents that can be used by road controlling authorities, maintenance engineers, and industrial painting contractors when carrying out removal or maintenance of lead-based paints on steel roading structures. It will enable them to comply with their statutory obligations, and minimise effect on the environment and risks to workers and public health. Section IV contains a generic standard specification for the cleaning and coating of steelwork. It sets out information to be supplied by the owner, and requirements to be met by the contractor; and includes standards for coating materials, surface preparation and contamination containment. Report series

Section I - Results of surveys
Section II - Code of conduct
Section III - Guidelines
Section IV - Model specification (report on this page)
Keywords: lead paint removal, risk assessment, maintenance painting, bridges