DAY 2 SESSION 1 ROD ELLIS ROAD ASSET MANAGEMENT AN APPROACH FOR THE ROAD MANAGER

Transcription

1 DAY 2 SESSION 1 ROD ELLIS ROAD ASSET MANAGEMENT AN APPROACH FOR THE ROAD MANAGER September 2004 Mr Rod Ellis BEng (Civil), MBA, GAICD, MIEAust, CPEng Director, Tonkin Consulting ABSTRACT In today s environment, Local Governments face the continual challenge of maintaining the condition of their road assets for less money. The age of road assets will continue to climb in a political environment where asset management is not given priority when compared to other funding demands. Road managers tend to accept the funding restraints rather than consistently presenting reliable information documenting the need for additional funding. By continuing to limit funding on road assets, and as a result allowing the network condition to deteriorate, the problem is effectively deferred to the next generation of Council members and practitioners. Without adequate information, Councils are deferring the problem rather than making informed funding decisions now. The aim of this paper is to create awareness in Councils of the need to develop reliable deterioration models on which to base future funding decisions. A road surface management methodology is presented as a basis for the development of systems and tools to assist in managing the road network to ensure every effort is made to hand over information on the network in a responsible manner to the next generation of road managers. Works managers need to be encouraged to adopt a systematic approach to road surface management to meet the increasing demands brought about by legislative changes, community pressure and a deteriorating road network. This paper also aims to inform road managers, particularly in regional councils, that good systems and support is also available to make the adoption of a systematic approach to road surface management as effective as possible. INTRODUCTION Road surface management for sealed and unsealed roads in the built up and non built up areas requires a systematic approach, which includes: Appropriate segmentation of the network; Establishing relevant segment information; Developing a consistent methodology for data collection; Assigning additional priority factors (other than condition); The calculation of a priority index (PI) and seal condition index (CI); Scenario modelling for selecting budgets to achieve a target network condition; Establishing financial plans for the five, ten and twenty five year time frame; Monitoring implementation of cyclic maintenance strategies against the plan; Updating network condition progressively as treatments are undertaken; Re-rating the condition of the network at regular intervals (say five to seven years); Re-calibrating deterioration curves to continually improve the reliability of future predictions; Capturing relevant maintenance history to assess the performance of treatments over time; and Establishing the future consequence of do nothing or deferred maintenance. In addition to the systematic approach to cyclic maintenance, routine maintenance activities, handling customer queries, generation of works orders and inspection records all contribute to building up a knowledge base of the road network, if they are integrated into the system. Date: 19/08/04 Page: 1

2 This paper presents a framework for the road surface management process that has been the basis of the ALARMS pavement management software developed by Tonkin Consulting in the late 1980 s. This software is currently being redeveloped in association with Conquest Solutions, a developer and provider of the asset management software Conquest. Tonkin Consulting has worked closely with the City of Norwood Payneham and St Peters, Prospect and Walkerville in setting up and implementating road surface management processes for over a decade. The data collected in that time has been analysed to refine deterioration curves. The City of Holdfast Bay, Adelaide Hills Council, Berri Barmera Council, City of Victor Harbor, Light Regional Council and Campbelltown City Councils have also adopted the ALARMS system and the Practice has supported these Councils. Recently the City of West Torrens was the first Council to adopt the new and refined approach to road surface management within the Conquest structure and this will be presented as a case study to illustrate the road surface management process in action. ROAD SURFACE MANAGEMENT PROCESS The road surface management (RSM) process is a cyclic process as presented in figure 1. This process is presented for all stakeholders, and not just the road manager, so that all parties involved in decision making and implementation of road asset management buy into the process. The following summarises the process. Year 0 Condition data is collected for Sealed Built Up (SBU) and Sealed Not Built Up (SNBU) roads and Unsealed Roads within the network; Scenario modelling (25 years) and five to ten year plans are produced. Budgets are set for the five year plan with consideration given to the longer term requirements; The network is valued and the depreciation is calculated. The RSM tool will provide key information for this process; Resurfacing/reconstruction work is undertaken on an annual cycle by the following process: roads that were identified for treatment on the five year schedule are inspected and the actual treatment is established. If roads can be deferred then roads next in order can be inspected; Once the resurfacing program is complete the system needs to be updated, revised surface condition assigned and the actual treatments recorded; and The Surface Condition Index (CI) is recalculated for the entire network at the end of Year 1 to compare actual expenditure/network condition against planned expenditure/network condition. Year 1 A report is presented on the network condition as a result of actual work undertaken in the previous year; An assessment of the network deterioration is presented if changes in funding are approved; An annual works program is presented; and The resurfacing/reconstruction process is repeated as for Year 0. Year 2 to Year 4 The process is repeated as for Year 1. Year 5 The network condition should be resurveyed. The deterioration model is then re-calibrated by assessing the roads that were not treated in the period against predicted deterioration models; The network is then modelled for the 25 year planning timeframe and a revised five or ten year schedule is produced for resurfacing and reconstruction. The cycle then continues and the maintenance history that is built up begins to provide important information for future road managers. This is important in evaluating the performance of the selected resurfacing treatments in particular where innovative use of new material types is undertaken (eg polymer modified surfacings). Date: 19/08/04 Page: 2

3 Figure 1 Road Surface Management Process Flowchart Date: 19/08/04 Page: 3

4 KEY ELEMENTS OF THE ROAD SURFACE MANAGEMENT PROCESS The Road Surface Management process can be used for the development of the road surface management system within Councils and consists of five key elements as follows: Data Entry Data Analysis Financial Modelling Treatment History Knowledge Base Reports Data Entry The network needs to be segmented and appropriate information included to categorise and define the segment (eg surface type, length, width). For each segment, condition data is required to evaluate the condition of the segment in comparison to an as new condition. A logical data set is required for sealed built up, sealed not built up and the unsealed network. Data Analysis An analysis is required to transform the condition data into a condition index, which provides a score that is used to compare the condition of each road segment. In addition to condition, other factors such as traffic, soil type, road usage and road importance can assist in prioritising the various segments for maintenance. Modelling Based on historical data, deterioration curves are used to develop five, ten and twenty year plans for various expenditures. This will allow an evaluation of network deterioration for various budget scenarios. Treatment History By recording the time and type of treatment, a knowledge base can be developed to keep a record of treatments. This will greatly assist in the transfer of knowledge in the event of staff changes and will assist in evaluating treatment performance (in particular the use of new surface material technologies). Reporting Reporting is a fundamental tool for the Works Manager to present information to decision makers. This includes: Condition reports (worst first and alphabetical listing of road segments); Network Replacement Cost; Grants Commission Reports; AAS27 Reporting; Maintenance History; and Integration with GIS enhances reporting functionality. The road surface management process is primarily designed to manage the resurfacing strategy for the Council road network. However the data stored in the system will also assist in broader assessments of the road network. In Victoria, Management Plans are being enforced for risk management purposes and in response to the road management legislation. This may be a future requirement in other states. Accordingly, the discipline of introducing systems within Council is likely to become of greater importance in the future.

5 Within South Australia there has been significant work undertaken by the Grants Commission in establishing Cost Relativity Indices (CRI) and the development of the Roads Infrastructure Database Report Road functions have been defined across the state and are used in the general purpose grant methodology (ie Sealed Built up, Sealed Non Built up, Unsealed Built up, Unseal Non Built Up, and Unformed). Within the state there is a GIS database that includes information on the states local road network. Road categories have been identified including Freight, Tourism, and Social and across the state regional plans have been identified. Studies have been undertaken on the development of factors affecting road reconstruction and maintenance costs including Soil, Rainfall, Drainage, Materials Haulage and Traffic volume. The LGA has been proactive in supporting local government in providing strategic direction and leadership in infrastructure and asset management. The Asset Management Advisory Committee (AMAC) was established in direct response to the Wealth of Opportunities Study. AMAC is currently overseeing a mentoring program that is currently being implemented in 20 Councils to facilitate the preparation of asset management plans. Within SA, roads (both sealed and unseal) comprise a significant proportion of the asset base under the control of Councils. This is demonstrated on the chart below. The implementation of systematic road surface management processes across all Councils will enable Councils to respond to the growing pressure to implement asset management plans and to respond to funding constraints and to report effectively to the LGA and Grants Commission and other government authorities. SA Local Government Infrastructure Current Cost Stormwater Gravel Roads, Bridges and Footpaths Buildings Steds Parks and Other Seal Roads WHAT ARE THE HISTORICAL DRIVERS FOR ROAD SURFACE MANAGEMENT? Asset Management principles where introduced in the early 1970 s. In the late 1980 s the SA Public Accounts Committee adopted accrual accounting and balance sheets for Local Government. In 1991 the draft AAS27 was released bringing Assets into account. In 1995 AAS27 was issued, formally requiring infrastructure assets to be reported in the operating statements including a statement of financial position and depreciation. In the late 90 s these changes drove activity in identification, valuation and depreciation of assets. As we begin the new millennium there are now signals being sent from Government for improved asset management. In addition further funding through Roads to Recovery is giving some signals that asset management is an emerging requirement at all levels of Local Government. Since the late 1980 s Tonkin Consulting has been approaching road surface management from an engineering basis, which is in contrast to the accounting drivers of the 1990 s. As a result, we have well developed deterioration models within the City of Norwood Payneham and St Peters and the City of Prospect that provide a sound basis for longer term road surface management planning for local roads within the metropolitan area of Adelaide. These models could be applied to the regional Council areas initially, and refined to suit the local area conditions, once data becomes available in the local area.

6 The advancement of technology (in particular GIS and database programming) sees the emergence of software tools that can greatly assist Councils in the analysis and modelling of road condition data. These tools, if effectively used to meet Council s business requirements for information, can greatly assist technical staff charged with the responsibility for road construction/maintenance. In the remainder of this paper, a recent project undertaken for the City of West Torrens will be used to demonstrate the road surface management process as applied in practice, using the concepts being developed in the new RSM (formerly ALARMS). DATA ENTRY Network Types Three network types are defined for data collection and analysis, in line with the Grants Commission. These are: Sealed Built Up (SBU) Sealed Not Built Up (SNBU) Unsealed For the City of West Torrens SBU was used. Segment Information The segment information was transferred from the existing database, which included hierarchy (major, feeder and local roads), traffic, surface type, road length and width and a range of other useful information. This information is used for reporting. Condition Data Condition data was collected for each segment of the sealed network. This was undertaken using the Australian Road Research Board s (ARRB) purpose built Digital Imaging Survey Vehicle, which collected digital images at 10 metre intervals. Measurements for roughness, rutting and texture were also collected and the digital images were used to rate the visual defects against the ALARMS rating system. This rating allowed the information to be loaded into Conquest in a format that was compatible with the ALARMS rating methodology. Priority Data The intent of the priority data is to rate each segment taking into consideration factors other then condition. Potential freight usage, social importance and tourism factors could be developed to align Council s prioritie with those of the Grants Commission. For the West Torrens Project usage was simply categorised by traffic volume (major, feeder and local streets) and the roughness measurements were also used in consideration of priority. This is an area that will be developed further at West Torrens now that the structure and asset hierarchy has been setup within Conquest. Other Data Falling Weight Deflectometer (FWD) measurements were taken of 56km of the road network to review the strength of the more heavily trafficked roads. This information was also collected by ARRB and issued to Tonkin Consulting for analysis. DATA ANALYSIS Condition/Priority Index The condition index is calculated by segmenting major roads, feeder roads and local roads, selecting seven defects for each and applying a weighting to each defect. This allows the road manager to strategically decide on the basis for the maintenance plan.

7 For the West Torrens project greater strategic importance was placed on surface condition of local roads to enable control of surface ravelling due to binder oxidisation effects on these lightly trafficked roads. For major roads, load induced cracking and deformation are critical early warning signs for pavement distress under traffic. By assigning the weighting based on hierarchy, the road manager is able to better focus on maintenance priorities. The seal condition index is then calculated for segments within each hierarchy type. The calculated CI relates to surface condition and provides an indication on the likely cost and timing of treatment. To assist in prioritising the need for maintenance on the network, the roughness of each segment, measured in International Roughness Index (IRI) and also the Structural Number for roads were calculated from FWD results. This enabled the road segments to be prioritised with consideration to the surface condition (CI), roughness and structural adequacy. For the more heavily trafficked roads Equivalent Standard Axles (ESA s) were calculated based on traffic classification data to assist in prioritising roads with significant traffic. MODELLING Modelling was undertaken for the City of West Torrens network with deterioration curves developed based on a decade of deterioration modelling undertaken by the Tonkin Consulting for neighbouring Councils. It was considered reasonable to apply the deterioration models calibrated for other local councils to the local road network in West Torrens. However, given the heavy industry within the Council area the deterioration curves for major roads and feeder roads were adjusted. The purpose of the modelling was to assist in establishing an optimal long term funding projection against a desired network condition level. The modelling provided a logical priority order and indicated treatments in a particular year based on a 20 year period. This modelling will assist in understanding future impacts of funding decisions made today. Development of Five Year Capital Works Plan Annual budget scenarios provided an indication of future network conditions. By deciding on the budget scenario that was best suited to Councils requirements, a five year plan was developed to establish an optimum funding model and to assign a priority list of roads for treatment. The development of the model for West Torrens was based on a 20 year life cycle. Two scenarios were modelled. Scenario 1 Scenario 2 $5 million/annum - maximum annual budget $3 million/annum - maximum annual budget These budgets included 45% overheads for minor and major resurfacing and 10% for rehabilitation and reconstruction. No allowance was made for kerb and gutter replacement, which required additional funds. The model established that over the next five years an average budget of $2 million/annum will be satisfactory to maintain the network. This was due to the high proportion of the network that was still in good condition. However, in five to ten years, as roads become scheduled for resurfacing treatments, additional funding is predicted to be required in order to maintain the network condition. This was demonstrated from the network condition difference between Scenarios 1 and 2 from 2012 onwards, as shown in the charts below.

8 It was recommended that the network be resurveyed in 2010 to validate the predicted budget requirements and road condition. The results of the two model runs are presented below in graphical form. Maximum Annual Budget Scenarios - $$/annum $6,000, $5,000, $4,000, Annual Expendature $3,000, $2,000, Scenerio 1 Scenario 2 $1,000, $ Year Network Condition forcast for 2 Annual Maximum Budget Scenarios Condition Index Scenario 1 Scenario Year From the analysis of data, and by inspecting the road network increased funding will be required to maintain the netwrk in good condition (ie above CI 80) in the five to ten year time horizon. Allowing the network to deteriorate below CI 80 will result in major expenditure to bring the network back to CI 80 from 2011 onwards. Assuming $5 million is spent from 2013 the Net Present Value (NPV) to achieve CI 80 at 2024 is $40.5 million. Assuming $3 million is spent from 2010 and assuming major works are undertaken in 2024 to rebuild the network to change the CI from 65 to 80 the NPV would be $84 to $97 million. Accordingly ongoing funding in a responsible manner to maintain the network will save Council significant funds in the future.

9 BUDGET OPTIONS FOR THE CITY OF WEST TORRENS The modelling undertaken for the City of West Torrens has confirmed that over the next five years $2 million/annum will be an appropriate level of funding to maintain the surface condition of the network at acceptable levels. However, in addition to surface condition, roughness and significantly trafficked roads needed special consideration. Seal Condition The following diagram presents a snap shot of the proportion of the network needing treatment in the next 5 years based on surface condition, and the likely cost of treatment. The roads identified for treatment totalled $7.1/million (including overhead costs). This level of funding broadly covers the work needed to maintain the surface condition and waterproof the pavement asset to protect the pavement from deterioration. Network needing Treatment in 5 years based on Surface Condition No treatment Minor reseal Major reseal Rehabilitation Reconstruction Roughness The chart below provides a snap shot of the network with respect to roughness. Proportion of network requiring treatment to correct Roughness Acceptable Roughness High Roughness Unacceptable Roughness

10 From a network perspective it would cost $14 million to treat roads classified as unacceptable, and $8 million to treat roads classified with high roughness. Little correlation was found between seal condition and roughness and based on site inspections and analysis of the raw data, roads with high roughness result from whole of pavement shape loss rather then the integrity of the seal. Under current funding constraints it was not possible to treat these within a 5 year time period and is a longer term consideration. Given the importance of protecting the pavement asset on a network level, it is appropriate to treat roads of high roughness as longer term projects subject to funding and was prioritised based on the importance and usage of the road. Roads of Significance 56 km of local government roads within the City of West Torrens were tested for pavement strength using the falling weight deflectometer. Within these roads, Council staff identified those that were of importance and that had a history of pavement defects. From analysis of the traffic count data, a 20 year equivalent standard axle (ESA) traffic loading was calculated. ESA is based on the cumulative axle loading on the pavement over its life. ESA s are a fundamental measure for pavement design. Roads above N20 = 5 x 10 5 are no longer considered lightly trafficked roads and roads above N20 = 1 x 10 6 require a significant pavement for long term performance. In addition to seal condition and roughness these roads are of strategic importance to industry and development within the Council area. The roads have shown deterioration in sections and some did not appear in the priority list due to segment definition and/or low roughness. However due to localised heavy traffic, and as a result localised pavement distress, these roads were identified as needing rehabilitation or reconstruction. With consideration to the FWD testing and the visual inspection, together with roughness and seal condition data, and based on discussions with Council staff, a list of roads were flagged for special treatments in the next five years for a total cost of $1.7 million dollars over the five year period. Based on the above analysis the annual funding breakdown is presented below. Breakdown of $10 million Expenditure over 5 years $ Million's Seal Condition Significant Roads Roughness Criteria

11 TREATMENT HISTORY/KNOWLEDGE BASE To enable the City of West Torrens develop a knowledge base, the system will be configured to enable the treatment history to be recorded once new maintenance work is undertaken. If this is updated annually over time a comprehensive history of maintenance will develop. Further information and knowledge will begin to build up within the system that can be transferred should the current road managers move on. This is particularly important in an environment of high staff turn over and the tendency to reinvent the wheel and as a result lose knowledge of prior work. The critical component of this process is to commit to keeping a single repository of information that can be used in the future for decisionmaking and deterioration monitoring. Furthermore, where new technologies are trialled, the performance and benefits can be monitored to continuously evaluate and improve treatment selection. In the future in South Australia it is unlikely funding will meet the needs of the works managers, and as a result the level of service of the road network will continue to decline. The development of the knowledge base for each Council area will assist in learning from past experience and provide good information to assist in the selection of appropriate treatements to make the funding that is available going further. REPORTS The reports generated by the road surface management system were developed to suit the City of West Torrens requirements for an annual and 5 year works program. Within the Conquest system reports will be customised over time to suit the changing needs of Councils. A key element of reporting is to provide information at all levels, from the field superintendent through to funding bodies. A degree of flexibility is being provided in this regard. MAINTENANCE STRATEGY FOR WEST TORRENS CITY COUNCIL The data collection, analysis and modelling undertaken for the City of West Torrens has identified that an average annual budget of $2 million/annum should be spent over the next five years, to maintain the network so that a backlog of maintenance is not built up. The longer term prognosis is that additional funding will be required from 2011, due to the high proportion of roads that will require resurfacing. It was recommended that this should be confirmed with another data collection process in The network requires an integrated approach to asset renewal, while maintaining strategic roads to an acceptable standard and managing the expectation of rate payers with respect to roads with high roughness. The recommended maintenance strategy was presented in a five year works program. The priorities of roads earmarked for treatment are based on the following methodology: 1. Treat roads at a CI requiring minor reseals and where money is left over treat roads requiring major seal, then rehabilitation then reconstruction. This is known as the stitch in time approach aimed at obtaining wide treatment coverage of the network. 2. Roads identified with heavy traffic were flagged and additional funds were allocated to maintain these roads. 3. Roads with high roughness that were scheduled for resurfacing were allocated additional funds to undertake shape correction/reconstruction. 4. Where there are gaps in the priority list, roads with high roughness or strategic roads have been pushed up in the priority order.

12 The maintenance strategy presented to Council had a robust basis to preserve the road network and was well received at all levels of Council. Council advised that they had been waiting for some time for a systematic approach to understanding the condition of the network, given that the last data capture was in There is a commitment to keeping the system updated and linking the Works Depot to the system. This will allow further advances in a corporate approach to road surface management. CONCLUSION The work undertaken by the Practice over the last years, and in particular the recent redevelopment of ALARMS to RSM will provide a state of the art tool, within the Conquest data structure, to further support our Local Government clients in road surface management. The West Torrens Pilot project has assisted in testing the modelling tool, and provides a sound basis for data collection, analysis and modelling of local roads in the metropolitan environment. The Practice is currently negotiating with a regional council to pilot the system for regional areas to further develop the SNBU and Unseal data sets. This paper has presented a methodology which is aimed at creating awareness at all levels of Council of the need for a committed approach to systematic road surface management. Systems are available to the Works Manager and support services can be provided to embed an integrated road surface management system within any local government area. ACKNOWLEDGEMENTS The author wishes to acknowledge with appreciation Angelo Catinari and Joe Ielasi of West Torrens City Council for allowing the West Torrens Pilot Project to be used as a case study for this paper. The author also wishes to acknowledge Mr Paul Robinson and Mr Bruce Clayton of ARRB for their efforts in collecting the data and rating the network and Peter Brooks of Conquest Solutions for his programming expertise in setting up the deterioration model. REFERENCES Tonkin Consulting/West Torrens City Council, Financial Year Road Network Capital Works Paper, July International Local Government Asset Management Conference papers, May 12/ A 20 minute postcard from SA, David Hitchcock. Asset Management, The Australian Journey and Learnings, Chris Champion. AUTHOR BIOGRAPHY Mr Rod Ellis is a Director of Tonkin Consulting. In this role he provides specialist pavement design and management advice for projects ranging from local roads to major arterials. Rod is the pavement designer for Port River Expressway Stage 1. Rod has a passion for developing a complete solution for Local Government in road surface management and has been working on the redevelopment of the ALARMS software in consultation with Local Government clients for several years. Rod also oversees the business development of the Spatial Information System Group within Tonkin Consulitng, which is a strategic partner with MapInfo. Rod is a member of the Asset Management Advisory Committee (AMAC) and has a desire to see Local Government implement a systematic approach to road surface management.