OVERVIEW: Treatment Length Segmentation KEY POINTS

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1 OVERVIEW: Treatment Length Segmentation KEY POINTS Treatment Length Segmentation: Should section the network into uniformly performing contiguous sections of road that are performing differently from the adjacent sections Is the basis for how the road network will be managed Is a key input into forward works programme development Needs to consider appropriate section lengths for effective and efficient programming Needs to be maintained when performance is found not to be uniform Needs to be updated after renewal works Does not split sectioning at features along a road such as speed humps Introduction This overview document is intended to provide high level support and direction with understanding the criticality of maintenance activity data, and how to maintain this dataset. Any relevant current industry guidance material and case studies have been referenced where they provide more detailed assistance. It is important to remember that suitable quality assurance processes are needed for recording the activity and the acceptance of the data so as to have confidence in its accuracy. What are treatment lengths? A treatment length is defined as a uniformly performing contiguous section of road, and performing differently from the adjacent sections. Treatment lengths for sealed pavements are generated initially on the major top surfaces within each road. These can then split be at changes in: Traffic volume or loading (or pavement use) Number of lanes (seal width) Pavement construction Pavement type (thin surfaced flexible, structural asphaltic concrete, bridge, concrete) Urban/Rural flag ONRC category Terrain (Flat, Rolling, Mountainous) Treatment lengths do not need to be split at features along a road where there is no change in performance of the adjacent sections. These features are typically on the urban network and include traffic calming devices (ie speed humps), narrow strips of interlocking blocks/concrete, etc. that are less than 10m in length. Treatment lengths for unsealed roads are normally generated based on carriageway starts and ends. Segmentation of unsealed treatment lengths are not covered by this document. Why are treatment lengths important to me? Treatment Lengths are interconnected with the majority of network management decisions. They bring the control of network maintenance management down to a project level. It therefore becomes particularly important to consider the practical implication of defined Treatment Lengths on short and long term goals and objectives for the network. A treatment length is defined as a uniformly performing contiguous section of road, and performing differently from the adjacent sections Version 1.0 Page 1 of 10 16/05/2018

2 OVERVIEW: Treatment Length Segmentation What are they used for TLs are the base section of roads used in road maintenance and management system in New Zealand and therefore a fundamental part of network management regime. Below are the primary uses of these: Forward works programme development Running the Treatment Selection Algorithm (TSA) Pavement deterioration modelling (ie dtims) Asset performance analysis Visual RAMM road condition rating section generation Condition trend reporting Asset valuations Allocation of maintenance intervention strategies Intervention effectiveness reporting Reporting internally and externally including funders When should I maintain the Treatment Length segmentation? Treatment length segmentation needs to be maintained. Below are situations where sectioning may require reviewing and updating: When it becomes obvious that a treatment length is not performing in a uniform manner. This is currently the case when renewals are applied to a portion of TLs, reflecting the performance disparity. This situation should be minimal if treatment lengths are created and updated properly. In other words, Treatment lengths need to be revised when inconsistency in performance is observed. The renewal treatments can then be applied to the new treatment lengths. When treatment lengths are required to be revised due to changes to any of the configuration criteria such as road widening, significant change in traffic, etc. The new treatment length must perform homogenously over its length with all other configuration criteria remaining consistent. What is the consequence if they are wrong? As mentioned treatment lengths are the basis on which the pavement and surfacing assets are maintained. If treatment lengths are not segmented into uniformly performing sections it will reduce the quality of outputs and decisions made. RAMM summarises data from other RAMM tables into the treatment length table. This function summarises spatial data such as surfacing data, manual rating data and high-speed survey data into a single value for the treatment length, such as a single surface date, traffic volume and loading, average texture depth, average SCRIM value etc. With the aggregation of data to treatment level through the summarise process there is a risk that the performance of an individual treatment length is not correctly reflected if the section is not uniform. Conclusion Good treatment length segmentation into uniformly performing sections is a key input to allow the effective and efficient management of pavement and surfacing assets. The consequences of poor segmentation are significant with a reduced confidence and accuracy of the outputs of processes using these as an input. References State Highway Asset Management Manual (SM020) State Highway Database Operations Manual (SHDOM) Sectioning of Road Data for Pavement Management, Dr Chris Bennett RAMM Road Condition Rating & Roughness Manual Road Efficiency Group (REG) is a collaborative project between local government and the NZTA Transport Agency. For more information, please contact: Road Efficiency Group RoadEfficiencyGroup@nzta.govt.nz Contact - TBC Version 1.0 Page 2 of 10 16/05/2018

3 OVERVIEW: Surfacing Data KEY POINTS Surfacing Data: Is a record of surfacing works completed on your road network. Should represent the physical asset and include the location, dimensions, date, expected life and material attributes of the surfacing. Is a key dataset in our Asset Management processes. Is the foundation that road asset management tools build on and needs to be accurate, complete and up-to-date. Can specify in contract documents what data is to be collected, who is to collect it and when it is to be delivered. Should include recording the Works Origin and Lane Coverage fields to improve the quality of the results reported for the Cost Efficiency 1 to 3 ONRC Performance Measures. Introduction This overview document is intended to provide high level support and direction with understanding the criticality of pavement surfacing data, and how to maintain this dataset. Any relevant current industry guidance material and case studies have been referenced where they provide more detailed assistance. It is important to remember that suitable quality assurance processes are needed for recording the activity and the acceptance of the data so as to have confidence in its accuracy. What is surfacing data? Surfacing data is a record of surfacing works completed on your road network. Activities that can generate surfacing data include renewals, rehabilitations, vested assets (eg. new sub-division works) and other construction projects. Surfacing data should represent the physical asset and include the location, dimensions, date, expected life, material and material attributes of the surfacing. Surfacing work represents a large proportion of a Road Controlling Authorities investment so the accuracy of the surfacing data is critical. Why is this data important to me? Surfacing data is a key dataset in our Asset Management processes. Accurate, complete and up-to-date surfacing data is the foundation for treatment length segmentation, renewals FWP development, pavement deterioration modelling, asset performance analysis and asset valuation, and is a key input in the ONRC performance measures. Other data (condition, traffic, maintenance cost, etc) can then be added to the foundation to enable a robust FWP or deterioration modelling but without accurate, complete and up-to-date top surface data you have no foundation to build upon. Where is the data used? Below are examples of where surfacing data is an input: Treatment selection / FWP development Pavement deterioration modelling (ie dtims) Asset performance analysis ONRC performance measure reporting Achievement reporting Asset valuation Customer responses Accurate, complete and up-to-date surfacing data is the foundation to enable a robust FWP, deterioration model and other analysis..0 Version 1.0 Page 3 of 10 16/05/2018

4 OVERVIEW: Surfacing Data How can I influence the accuracy, completeness and timeliness of my surfacing data? Some suggestions are: Contract documents can specify what data is to be collected, who is to collect it (eg. NZTA Level 1 certified) and when it is to be delivered. A Data Quality Plan that identifies the attributes to be recorded and the level of accuracy required. A Data Quality Plan that includes a level of data checks (desktop and field checks). RAMM surfacing tables Collected Surface Data Local Authorities across New Zealand use RAMM for recording their pavement surfacing inventory records. The adjacent figure shows the various surfacing tables within RAMM and their relationship. Surfacing inventory data is maintained in the Carriageway Surfacings table. All other tables are system generated through the Status Check summarise processes in RAMM Manager. Surface Material Look-up (includes Default Life) Treatment Length Table Summarised into Entered into Carriageway Surfacings Table Used to generate Surface Structure Table 3 views, which can be sectioned by carriageway or not How to achieve reliable ONRC Performance Measure reporting The following data fields have been added to the Carriageway Surfacing table to improve the quality of the results reported for the Cost Efficiency 1 to 3 ONRC Performance Measures: Works Origin Derived from the NZ Transport Agency s Works category. This field identifies whether surfaces are related to renewals, projects or vested assets. Lane Coverage This is the number of lanes the surface covers. ONRC Cost Efficiency Measures 1 to 3 are measured in lane km. Major surface Top surface Detailed surface Conclusion Accurate surfacing data is integral to expenditure decision making. All parties involved can have an influence on whether the data the TLA has is accurate, complete and timely. References State Highway Database Operations Manual (SHDOM) Data Standard for Road Management and Investment in Australia and New Zealand Chipsealing in New Zealand Road Efficiency Group (REG) is a collaborative project between local government and the NZTA Transport Agency. For more information, please contact: Road Efficiency Group RoadEfficiencyGroup@nzta.govt.nz Contact - TBC Version 1.0 Page 4 of 10 16/05/2018

5 OVERVIEW: Maintenance Activity Data KEY POINTS Maintenance Activity Data: For pavement or surfacing maintenance repair activity should be recorded in the RAMM maintenance cost table Needs to be complete, accurate and timely in terms of what was done, where, when, and why Quantity and location are more important than cost Completes understanding of the performance of a pavement and/or surface asset Is a key input into the development of a pavement and surfacing renewal forward works programme Introduction This overview document is intended to provide high level support and direction with understanding the criticality of maintenance activity data, and how to maintain this dataset. Relevant industry guidance material and case studies are referenced where they provide more detailed assistance. Suitable quality assurance processes are needed for recording the activity and the acceptance of the data for confidence in its accuracy. What is maintenance activity data? Maintenance activity data is a recorded summary of a maintenance activity which has occurred at either a specific location, or over a specific length of road. The maintenance cost table in RAMM was initially designed to capture pavement and surfacing maintenance activity only. However activity for other assets can be recorded, eg. footpaths, streetlighting, etc. Activity is recorded against a cost group, activity type and fault code. It generally reflects the maintenance of an existing asset. It is best practise across NZ Local Authorities to record maintenance activity data in the maintenance cost table in RAMM. Why is this data important to me? The accurate and timely collection and recording of reactive and programmed routine maintenance activity data is fundamental to assist road controlling authorities in managing and analysing their roading assets over time. There are significant benefits associated with recording maintenance activity data. Figure 1 shown the key uses of this dataset. Figure 1: Key uses of Maintenance Activity Data Is needed in an economic evaluation of treatment options (eg. NPV analysis) Asset management decision making Ability to assess historic quantities for use in pricing schedules during tendering To be maintained and updated frequently Is a key input into asset management decision making, long term planning and pavement deterioration modelling Renewals FWP Development NPV Analysis Better understanding of asset performance Maintenance Activity Data Pavement deterioration modelling Ability to quantify and analyse data over time, ie trend reporting Maintenance activity data completes the puzzle in terms of analysing asset performance and maintenance strategy effectiveness Version 1.0 Page 5 of 10 16/05/2018

6 OVERVIEW: Maintenance Activity Data Maintenance activity data for the pavement and surfacing cost groups are critical inputs for renewals FWP development, pavement deterioration modelling and net present value (NPV) analysis. As a minimum these cost groups should be recorded. The quantity of the recorded activity is of greater value than the cost. It is the quantity that provides the indication of asset performance. The data can be summarised at various network levels and reported in conjunction with such things as ONRC categories, asset age, asset condition or renewal costs. Put simply, without maintenance activity data, you do not have all the pieces of the puzzle to achieve good asset management. How to achieve robust maintenance activity data The most important steps to ensuring robust maintenance activity data is recorded 1. To do it in partnership with the maintenance contractor and have them take ownership for the recording of complete and accurate data. 2. Have a local authority resource that will understand the data and take ownership for its overall accuracy and completeness. Each local authority should consider the extent of the data they wish to record and agree the cost groups, activity and fault types. Each maintenance contract item should then be linked to a cost group, activity type and fault code and the units in a standardised manner. Data should be provided on a monthly basis and provided for data review and acceptance before loaded into RAMM. The adjacent figure shows the process which the data should follow. It is best practise to load activity into the maintenance cost data table in standardised units. This makes the data usable for asset performance analysis, FWP development and pavement deterioration modelling. Perform maintenance activity Contractor records required fields Transfer/load data to RAMM Maintenance Cost table Provide to contractor Data reviewed for incomplete or invalid records Validate completeness, location, quantities Document incomplete or invalid data Provide to contractor Document loaded data (monthly, annually) Figure 2: Maintenance activity data review/loading process Conclusion The roles of all parties should be clear for recording maintenance activity data. RCAs, contractors and consultants should all understand the importance that complete and accurate data has for decision making of the asset owner. As a minimum, contractors should be briefed on record the data, what quality assurance is required, the frequency and delivery process of the data and the acceptance process of the data. References State Highway Database Operations Manual (SHDOM) RIMS Roading Asset Maintenance Cost Guidelines Data Standard for Road Management and Investment in Australia and New Zealand Road Efficiency Group (REG) is a collaborative project between local government and the NZTA Transport Agency. For more information, please contact: Road Efficiency Group RoadEfficiencyGroup@nzta.govt.nz Contact - TBC Version 1.0 Page 6 of 10 16/05/2018

7 OVERVIEW: Traffic Count Data KEY POINTS Traffic Count Data is: A record of the traffic volume and possibly loading on a defined section of road for the period the the counter was collecting data To be collected in accordance with a strategy and structured programme The basis for developing traffic estimates for the network Needed to understand the current and changing traffic demand on the network A key input into our asset management processes including forward works programme development 80% of the network VKT can typically be counted on 20% of the network Introduction This overview document is intended to provide high level support and direction with understanding the criticality of robust traffic count data, and how to develop a traffic count strategy and structured count programme. Any relevant current industry guidance material and case studies have been referenced where they provide more detailed assistance. It is important to remember that suitable quality assurance processes are needed for the physical collection of the count data to have confidence in its accuracy. What is traffic count data? Traffic count data is a representation of the level of demand at a location on a network for the period that a counter was collecting data. This level of demand is recorded in terms of average daily traffic (ADT), speed, peak hour traffic and traffic mix. Traffic mix is the percentage distribution of the ADT by vehicle classification (car, light commercial vehicles, medium commercial vehicles and heavy commercial vehicles). To collect classified data an appropriate counter technology is required. It is common practise across NZ Local Authorities to record traffic count data in RAMM. Types of common current traffic counter technologies include: Manual counting Single tube (volume only) Twin tube (speed and classified by axle groupings) Induction loops Telemetry sites Why is this data important to me? Traffic count data is a key input into a number of decision making processes. Robust traffic count data allows us to understand the current and changing demand on our networks. It is the basis for developing traffic estimates for the full network beyond those sections that are counted. Without good traffic data it is very difficult to reliably plan maintenance management activities to achieve a desired outcome and make evidence based investment decisions. Traffic count data provides the level of traffic activity in terms of volume, loading and growth. It is a key input on estimating the level of demand on a network. Version 1.0 Page 7 of 10 16/05/2018

8 OVERVIEW: Traffic Count Data Where is this data used? The adjacent figure shows some key areas and aspects where traffic counting data is used. Traffic count data recorded in RAMM is summarised into other tables including the carriageway and treatment length tables. These core tables are commonly the basis on which a roading network is maintained and management efficiently and effectively. What is the consequence of poor traffic count data? There are significant issues associated with poor traffic count data. Some examples include: Poor estimation of the non-counted network Bad funding decisions Poor understanding of renewals need and forward works programme development Poor customer service Poor asset performance analysis and reporting Incorrect allocation of asset life cycles Incorrect traffic management levels Poor asset risk management Inappropriate resurfacing or rehabilitation designs Understanding of traffic patterns (i.e. growth) How can I develop a structured count programme? A structured count programme should look to maximse resources to gain information on the current and changing demand on the network. A stratified count programme fitted to a rationalised network achieves greater coverage of the count programme through the use of traffic links to join carriageway section of similar traffic activity. The structure traffic count programme should include: Frequently repeated sites (i.e. annual) to understand changes in demand either through growth and/or traffic mix. Geographical and use coverage of network (eg rural, industrial, commercial, quarries, forestry blocks, dairy operations, etc) Current best practise is to count 80% of the network vehicle kilometres travelled. The concept behind this is that the greater the proportion of the network demand counted, the smaller the proportion that has to be estimated. This should result in a lower error and a more accurate dataset. As a guide 20% of the network typically carries 80% of traffic activity. The frequency of the rotational sites can be structured to align with budgets, resources, etc. Conclusion Traffic count data is the basis for developing estimates for the entire network. This is a key dataset for understanding the current and changing demand on the network. A structured programme targeted at the sections of network carrying the greatest proportion of network VKT can reduce errors in estimation. References RIMS Guideline for Traffic Counting Road Efficiency Group (REG) is a collaborative project between local government and the NZTA Transport Agency. For more information, please contact: Road Efficiency Group RoadEfficiencyGroup@nzta.govt.nz Contact - TBC Version 1.0 Page 8 of 10 16/05/2018

9 OVERVIEW: Traffic Estimate Data KEY POINTS Traffic Estimate Data is: An estimation of the traffic volume and loading on a defined section of road The initial basis for the network ONRC categorisation Needed for the effective and and efficient management of the network A key input into forward works programme development To be maintained and updated frequently Introduction This overview document is intended to provide high level support and direction with understanding the criticality of robust traffic estimate data, and how to maintain this dataset. Any relevant current industry guidance material and case studies have been referenced where they provide more detailed assistance.. What is traffic estimate data? Traffic estimate data is an estimate of the level of demand across the entire network built up on a carriageway section basis. This includes both traffic volume and classification (mix). It is necessary to estimate the level of traffic demand on a network as: It is not practical, affordable, or necessary to count every carriageway on a network. Actual count data is representative of the period (commonly 7 days) the data was collected. The recorded traffic volume (ADT) may require adjustment to account for seasonal variations, etc. Why is this data important to me? Traffic estimate data is a key input into a number of asset management and decision making processes. RAMM can hold a traffic estimate record for each carriageway section on a network. Without good traffic data it is very difficult to reliably plan maintenance management activities to achieve a desired outcome. Where is this data used? The adjacent figure shows some key areas and aspects where traffic estimate data is used. Traffic estimate data is the base data for defining the level of traffic activity on the network both in terms of volume and loading. Version 1.0 Page 9 of 10 16/05/2018

10 OVERVIEW: Traffic Estimate Data Traffic count data recorded in RAMM is summarised into other tables including the carriageway and treatment length tables. These core tables are commonly the basis on which a roading network is maintained and management efficiently and effectively. What is the consequence of poor traffic estimate data? There are significant issues associated with poor traffic estimate data. Some examples include: Bad funding decisions Poor understanding of renewals need and forward works programme development Lack of understanding around policy/guideline consequences Poor customer service Poor asset performance analysis and reporting Incorrect allocation of asset life cycles Incorrect traffic management levels Poor asset risk management Inappropriate resurfacing or rehabilitation designs Understanding of traffic patterns (i.e. growth) How to maintain traffic estimate data? Timing Traffic estimate data should be maintained either following the completion of counting activity, or periodically to align with your business processes. Adjacent is the minimum frequency of updates recommended by ONRC category. You may however need to update estimates more frequently if your network is going through a notable change in demand. ONRC Categories High Volume to Arterial Primary and Secondary Collectors Access including Low Volume Minimum Frequency Annual 3 yearly 5 yearly How Both volume (AADT) and classification (traffic mix) need to be included in an estimate update. Volume should take account of growth with classification considering the environment (e.g. industrial, commercial). The structured count programme should provide the base data for updating the non-counted portion of the network. It is recommended when estimating the traffic mix you split your network into similar loading categories. These should consider ONRC category as well as separately identifying sections of the network with non-typical levels of traffic loading (industrial, commercial, CBDs, dairy, quarries/landfills, etc.) There are a number of options for updating your estimate data from manual to automated. The most appropriate for your network will depend on a number of factors including size of network, frequency of updates, resources, etc. Conclusion Complete, accurate and timely traffic estimate data is a critical component in our network and asset management processes. References RIMS Guideline for Traffic Counting Poor quality data can significantly impact our ability to plan and manage our activities to achieve a targeted outcome. Road Efficiency Group (REG) is a collaborative project between local government and the NZTA Transport Agency. For more information, please contact: Road Efficiency Group RoadEfficiencyGroup@nzta.govt.nz Contact - TBC Version 1.0 Page 10 of 10 16/05/2018