tamp apr 2009 - hertfordshire€¦ · web viewthe actual number of hcc structures could be in...

APPENDIX A

Hertfordshire County Council

Transport Asset Management Plan

Asset Performance Report 2009

Hertfordshire County Council: TAMP Annual Report 2009 1

Contents

Introduction

1 Transport Asset Management 2009 – Locally and Nationally

1.1 DfT Transport Asset Management Funding 2009

1.2 Highway Asset Management Quick-Start Guidance

1.3 Draft Guidance on Asset Management-Based Valuation

1.4 CAA and Use of Resources1.5 Confirm Implementation

2 The Carriageway Asset

2.1 Winter Damage2.2 Holistic Management of Cat.1 and

Cat.2 Service2.3 Work Streaming, Innovation and

Efficiency2.4 Asset Performance Indicators2.5 Programme Delivery 2008/092.6 Programme Planned for 2009/102.7 Future Projections and Options2.8 Carriageway Strategy and Objectives2.9 Deterioration Modelling2.10 Average Condition Indicator

3 Drainage

3.1 Pitt Review and Flood and Water Bill3.2 NETSWA and Surface Water

Management Plans (SWMP)3.3 HertsDAM System for Drainage

Inventory3.4 Condition / Performance 3.5 Programme Delivery 2008/093.6 Programme Planned for 2009/103.7 Work-Streaming / Efficiency / Innovation

3.8 Ongoing Issues

4 Footways and Cycle Tracks

4.1 Footway Network Survey4.2 Hierarchy review4.3 Performance4.4 Programme delivery 2008/094.5 Programme planned for 2009/104.6 Future Projections

5 Intelligent Transport Systems

5.1 ITS Infrastructure5.2 Summary of ITS Type Assets5.3 Key Issues5.4 Innovations and Efficiencies

6 Street Lighting

6.1 Street Lighting Service Review6.2 Programme Delivery 2008/096.3 Programme Planned for 2009/10

7 Structures

7.1 Headlines / What’s New7.2 Asset Inventory7.3 Condition and Performance7.4 Programme Delivery 2008/097.5 Programme Planned for 2009/107.6 Future projections and Options7.7 Key Issues


Introduction

The national impetus for transport asset management continues to gather pace with both the Department for Transport and HM Treasury adding their weight to the cause. Indeed the written statement supporting the Chancellor’s budget address earlier this year specifically identified the potential for significant efficiency savings that could be realised through wider use of transport asset management.

Budgets locally and nationally are under pressure due to the economic down turn, a situation unlikely to change in the immediate future. Consequently it is now more important than ever that the core principles of asset management – good, informed decision-making that leads to the best long-term outcomes as efficiently as possible – are applied rigorously to our services to ensure that we use our available resources as efficiently and effectively as possible.

Hertfordshire continues to be recognised as one of the leading practitioners in the asset management field and one which makes significant contributions to developing future projects. We remain committed to continue to develop and lead good practice in asset management to help us meet the competing challenges of improving services and increasing efficiency.

Rob Smith, Assistant Director (Transport Management)December 2009


1 Transport Asset Management 2009 – Locally and Nationally

1.1 DfT Transport Asset Management Funding 2009

Recognition and Reward for Hertfordshire

In 2008 the Department for Transport invited all local highway authorities to bid for additional funding, based on their progress with transport asset management. This initiative was intended to help authorities to progress transport asset management and to send a clear message from DfT that they support the process. The available funding was divided into two elements.

Element 1 funding was available to every authority and bidders were asked to demonstrate a commitment to the principle of asset management by showing that they were already undertaking basic asset management activities such as data collection and processing.

Element 2 funding would reward “authorities’ innovative use of data in making investment and maintenance decisions on the highway” and would be limited to 10-15 successful bidders.

Submissions were required before Christmas 2008 and the results were announced early in 2009, with the funds being made available in 2009/10.

Hertfordshire, in common with most authorities, were successful in Element 1, gaining over £375,000 of additional funding as a result.

We also submitted one of only 14 successful Element 2 bids, based on our pioneering work in asset management generally and carriageway deterioration modelling in particular. As a result of this Hertfordshire was awarded a further £500,000 of reward funding.

Some of the reward funding gained is being spent exploring the options for the future of the street lighting service and the remainder is being used the help repair some of the roads that were damaged during the severe weather in February 2009.

1.2 Highway Asset Management Quick-Start Guidance

More Guidance for UK Asset Management

During the summer of 2009 the asset management working group of the UK Roads Board published a suite of four new Highway Asset Management Quick-Start Guidance notes:

Getting Started Risk Assessment Levels of Service Life Cycle Planning

As the ‘Quick-Start’ title implies, these notes (and the first guide in particular) are primarily intended to help authorities that are just starting on asset management. However there is some useful information for all authorities included here and, perhaps more importantly, these guidance notes reinforce


the importance of asset management to the highways sector and, by potentially helping later-adopters to catch up, should help move the industry as a whole forwards.

1.3 Draft Guidance on Asset Management-Based Valuation

Asset Management links to Financial Information supporting WGA

A draft asset valuation code was published for consultation in the autumn of 2009. The code proposes changes to the way in which highway infrastructure assets are valued and accounted for and is likely to have a significant impact on local authorities’ accounts as and when these numbers hit the ‘bottom line’.

At the moment infrastructure assets are valued on an historic cost basis, meaning that the value of Hertfordshire’s highways in the county’s accounts is around £300m. Hertfordshire have been calculating asset values based on asset management since the original HAMP was published and informally quoting the figure of £4,000m as a more realistic value for the highway asset. Similar work done by other authorities has arrived at a similar conclusion – the current method values the highway asset at only a fraction of its true worth. The new draft code has been drawn up by HAMFIG (Highway Asset Management Financial Information Group). HAMFIG is a task group made up of representatives from a number of local authorities and DfT and it reports both to the UK Roads Liaison Group (on behalf of the highways community) and to CIPFA – the Chartered Institute of Public Finance and Accountancy (on behalf of the finance community).

The guidance is intended to replace the 2005 CSS guidance on asset valuation with a joined-up approach that uses asset management principles and systems to arrive at robust financial information about the asset, rather than treating valuation as a separate exercise.

The new guidance will also be IFRS (International Financial Reporting Standards) compliant, allowing it to support the Whole of Government Accounts (WGA) process. HM Treasury is committed to implementing the code as part of the WGA agenda and the draft timetable would see authorities starting dry-runs with some data as early as next year with full implementation for 2012/13.

The intention is that authorities should use good asset management techniques such as life cycle planning, which will be of value in the day-to-day management of their assets, to derive financial information such as the gross replacement cost, depreciated replacement cost and annual depreciation of the asset. This should ensure that data collected and decisions made in managing the asset support and reflect the reported financial information.

Hertfordshire has been actively involved in drafting the guidance, which draws on much of the good practice we have promoted over the years. We should therefore be well placed to implement it once the code is finalised. However, the financial information that authorities will be required to derive will include the annual depreciation of the asset – effectively the amount that should be spent each year to maintain the asset. This figure is likely to be significantly


higher than current maintenance budgets, both in Hertfordshire and nationally, and this may pose a number of challenges.

The consultation period for the draft guidance runs until 14 th December 2009 with the final version due to be published in February or March 2010.

1.4 CAA and Use of Resources

Value of Asset Management Recognised by Performance Audit

A number of examples of good practice in Transport Asset Management were used by Hertfordshire this year during the CAA (Comprehensive Area Assessment) audit. The example of the TAMP and the award of the grant from DfT recognising the approach to transport asset management in Hertfordshire were used to defend a key score in the Use of Resources KLOE (Key Line of Enquiry) and the Audit Commission acknowledged that it swayed their view. Use of Resources is a critical KLOE since it limits others in the group so if the authority is not seen as good at Use of Resources then good work elsewhere may go unrewarded.

Although asset management is specifically a part of the Use of Resources KLOE, in the past this has mostly focussed on property asset management. By extending this consideration to infrastructure asset management, Hertfordshire demonstrated the breadth of our work in the field and we were, in many ways, ahead of the field. Informal contacts with a number of other authorities have indicated that many are not yet being examined on the transport or infrastructure side of asset management for CAA although, from the guidance, it is clear that this is likely to change in future years. Indeed the work done on asset management based financial information (mentioned in 1.3 above) may well help to inform audit guidance on good asset management practice in the highways field as the equivalent property code has helped to inform auditing of that field.

As a consequence, good work and good practice in asset management is likely to continue to have a direct bearing on our CAA scores in the future as well as potentially figuring in our formal accounts.

1.5 Confirm Implementation

A New Asset Management System for Hertfordshire Highways

Autumn 2009 saw the start of the implementation of the Confirm system in Herts Highways. Confirm Highways is an integrated Asset Management and Maintenance System for managing the whole life cycle of highways assets from cradle to grave. The system provides a modular approach to the storage of highway inventories, valuation and risk assessment of highways assets, monitoring of their condition, and subsequent maintenance and management. At the heart of the system is a BS7666 Street Gazetteer and Network Register supporting multiple network referencing methods.

It takes over from HERMIS as the county’s main infrastructure asset database and will ultimately handle a wide range of functions including highways, street


lighting, bridges and structures, street works notifications, pavement management (UKPMS) and works ordering.

Confirm is built around links to GIS mapping, allowing easier access to, and display of, key information for users. Going forward it will be a key part of Hertfordshire’s asset management strategy for years to come as the effective capture and use of good data is at the heart of asset management.


2. The Carriageway Asset

2.1. Winter Damage – February 2009

2.1.1 Background and Analysis

The winter of 08/09 saw several periods of severe weather including an extended and severe period in February 2009 which was the worst in 20 years. The effect of this extreme weather took its toll on the condition of the road network.

Hertfordshire was in the process of conducting condition surveys on the network when the February snow started. We quickly repeated the surveys conducted just before the snow immediately after it had cleared. This meant we had surveys of the same sample of the network immediately before and just after the snow, which allowed us to calculate accurately the damage done to the network by the February snow event. These calculations show that the proportion of the sample in a poor condition increased from 10.5% before the snow to 16.2% after it – a relative increase of 54% in poor roads in just two weeks.

In order to return the network to its pre-snow condition, a number of options were analysed including a one-off up front investment or a longer-term sustained investment. The analysis shows that the one-off up front investment would be more cost effective than spreading the repairs over, say, a five year period.

The cost of returning the network to its pre-snow condition by means of a one-off investment is approximately £16m, over and above normal programmes of work; it is therefore fair to say that the exceptional weather in February 2009 did the equivalent of one normal year’s worth of damage in a two-week period.

2.1.2 Recovery Options

Hertfordshire added a Winter Recovery Programme to the 2009/10 IWP, investing over £3.5m of additional money (including much of the DfT reward funding detailed in 1.1 above) into treating some of the most heavily damaged roads.

The sites were identified and prioritised after the February snow had cleared using reports compiled that showed where there were significant concentrations of emergency repairs backed up by site visits and engineering assessments. They were formally added to the IWP in July 2009 and delivery is well under way at the time of writing with 78 roads due to be partly or completely treated in 09/10 under this programme.

Along with a number of other authorities, Hertfordshire is pursuing a claim for additional capital funding from DfT to help address the damage done. At time of writing that claim is still being considered.


2.1.3 Future Implications

Although the Winter Recovery Programme will address some of the more pressing needs, it will not be able to address all the sites in need of urgent repairs as a result of the severe winter weather.

Additionally, the damage to the network goes beyond the immediately urgent sites. Many roads will now need maintenance or repair several years earlier than they would otherwise have done. This could create an ongoing pressure in future years as roads that would previously have had several years of life left reach the point where treatment is needed more rapidly.

Finally, most of the annual round of condition surveys were carried out prior to the snow in February 2009. This means that the full impact of the damage will not be seen in our condition indicators until the next round of surveys for 2009/10 are undertaken (between October 2009 and March 2010). The results will be published in the summer of 2010.

2.2 Holistic Management of Cat 1 and Cat 2 Service

To ensure that Hertfordshire’s highway network is maintained in a safe condition for the travelling public, Hertfordshire Highways (HH) provides a reactive maintenance service. This primarily consists of safety inspections, Category 1 repairs (to emergency or urgent defects) and Category 2 works (for the repair of non-hazardous defects). Over recent years the cost of providing the Cat.1 service has increased significantly to unsustainable levels, prompting a review into this part of the maintenance service. A review of current arrangements for managing the Cat.1 and Cat.2 service to look for synergies and/or efficiencies was therefore included as item IA12 in the TAMP Improvement Action Plan. This activity was also included as a project under the HH Efficiency Group umbrella. The initial review was undertaken as part of TAMP development in 2008/09 and resulted in the production of a report titled “Cat 1 and Cat 2 Service Value for Money Study”, which was completed in January 2009 and submitted to management for consideration. Following completion of the report a working group, made up of staff from across Herts Highways, was set up to further develop some of the recommendations from the report and, in particular, determine how efficiency savings could be made. Reports detailing the options for achieving efficiency savings were submitted to the HH Performance Review Board (PRB) in June (draft) and October 2009. These options involved:

Increase client control of Cat.1 & Cat.2 service, by moderating levels of service and intervention.

Meet and maintain targets for the number of “84 day” Cat 2 work orders and apply stretch targets for these same orders under the Super Cat 2 programme.

Develop the range of cost effective maintenance process options (e.g. jet patching) and deploy them on a cyclic countywide basis.

The working group is currently progressing with the implementation of these options. In particular they have been tasked with ensuring that the new


arrangements for the revised Cat 1 level of service are in place and operating by April 2010. This has comprised the review and re-alignment of service standards for the identification and repair of highway faults/defects reported by the public with those found by HH’s own safety inspectors. This has involved considerable work to amend existing processes, decision making logic in the web based reporting and asset management systems and the training of customer facing staff. While it is too early yet to report definitively on the success of this initiative in reducing Cat.1 expenditure, the early indications are promising.

2.3 Work Streaming, Innovation and Efficiency

2.3.1. Work Streaming

Since the start of the 2008/09 programme in March 2008, the maintenance elements of the IWP have been fully work streamed. Work streaming is a process by which all schemes of a similar type are gathered together into groups (or ‘work streams’) to be delivered as a package by the same team, rather than programmes being split geographically for delivery in a particular area.

The process of designing, managing and delivering the schemes is undertaken by the same client team from start to finish, in close cooperation

with the appropriate designer, whether this is the Works Team (for ‘Walk and Build’ projects) or the Design Team (for other projects). This eliminates the need for handovers mid-project and reduces the scope for late-stage design changes by enduring that the same team takes the project from inception to delivery. This

improves the efficiency and certainty of delivery and allows better forward planning. It also puts the financial management and accountability in the same team as scheme delivery, ensuring that this key aspect is accorded due importance.

In order to ensure that we make the best use of the available resources, it is important that all parts of the scheme delivery process align with our agreed strategy to translate our overall objectives into the desired outcomes in the most effective way, as illustrated in Figure 1.

Hertfordshire County Council: TAMP Annual Report 2009

Corporate Objectives

Programmes and Budgets

Scheme Delivery

Agreed Outcomes

Fig.1

11

By grouping similar jobs into work streams we are better able to capitalise on economies of scale; we are also able to allow Design Team and Works Team partners, who now plan the delivery of the IWP, to programme these works streams to deliver the works as efficiently as possible which, again, contributes to efficiency.

For instance, by work streaming the surface dressing programmes we allow the Works Team to create a programme of works in which one site follows on from the next in a logical order. This means that the costs associated with bringing the equipment in and moving it from site to site are minimised, helping improve value for money.

There is still, of course, the need to consult more broadly during the programme development phase when schemes are being identified and defined. However, the work stream approach means the same team that develops the programme and undertakes those early discussion is the team that delivers the final schemes, helping to ensure that the final outcomes deliver what we originally intended.

This kind of arrangement helps to ensure that the whole process aligns with, and contributes to, HCC’s overall objectives and strategy. The inclusion of performance monitoring in the process allows us to close the loop and use learning from the current year to inform and improve future years’ programmes and, potentially, to generate further efficiencies. In this context performance monitoring could include checking the effectiveness and cost effectiveness of different processes and delivery methods as well as checking the various performance indicators against corporate and LTP targets and benchmarking against other authorities.

This information can be fed back into the option development process to help fine-tune programmes and strategies, as illustrated by Figure 2, which is extracted from the TAMP.

While this feedback and improvement cycle is, of course, possible under any regime, the work stream approach means that the process is capable of being much more immediate and responsive.

Finally, but perhaps most critically, the work stream approach helps to ensure that risk is managed in an appropriate way. Since the direct client team involved in a particular work stream is limited to a few individuals, it is much


Fig. 2

12

easier to maintain a high degree of specialist knowledge in a particular work stream, process or material. This in turn allows the client to understand and accept appropriate levels of risk, rather than having to rely on an external designer for advice when there is the likelihood that such advice will tend to err on the side of caution and advise a lower risk (and consequently higher cost) solution. A specialist client who better understands the risks involved is able to manage them better and thus contribute to better value for money.

2.3.1.1 Work Stream Risk Management – An Example

Before a road is surface dressing, it normally needs some preparation works to fix the worst of the defects before the dressing is applied. Particularly bad defects such as deep potholes will always need this, minor defects such as fine cracks will not. There is a category of moderate defects in between where a risk-averse engineer will patch the defect but a more value-focused engineer would accept the very small risk that further works might be needed in exchange for major savings in the preparation phase of the programme.

Over the last few years, since the Herts Highways surface dressing programmes have been work streamed, we have steadily brought down the proportion of the budget spent on preparation year-on-year. This has been achieved in no small part because of the active involvement of the client in the process and the consequent ability of the client to set and accept the risk at the most appropriate level, thus delivering better value for money.

2.3.2 Innovations, Trials and Efficiency

During the past year a number of trials of new or alternative materials and processes have been undertaken with the view to seeking better and more efficient ways to maintain the network and to ensure that Herts Highways stays abreast of new technology.

2.3.2.1 PACO Patch

Used for bedding and reinstatement of ironwork (manholes, gully gratings etc). The process is more expensive than conventional methods but trials suggest it is much more durable, meaning it may be a cost-effective option at ‘problem sites’ where the same item of ironwork has come loose several times and needed repeated repair. Trials have been undertaken and are being monitored; rates are being agreed for inclusion in the HH contract.

2.3.2.2 ‘Viatec’ Pothole Repair material

A pothole repair material that can be laid in wet conditions. The initial investigations into the suitability of the product have been carried out and trials using the product are being planned.

2.3.2.3 ‘Nu-Phalt’ Infrared patch repairs.

This process uses a gas powered heating source on a defective area of carriageway to raise the temperature and soften the road. The area is then re-worked with new material added as necessary to repair the road. This process produces a surface without joints, making it more durable, and reduces the


amount of new material that needs to be used in the repair. It is similar to some other proprietary processes and the tests will allow us to assess the properties of the different processes. Trials have been undertaken and further investigations into the application are being carried out.

2.3.2.4 German-Type Stone Mastic Asphalt (SMA).

A new road surfacing material used primarily in Germany has been trialled at St Anne’s Road, London Colney and is currently being monitored. The material has a different composition to the normal UK specification SMA which may make it more durable. Costs are comparable to the UK equivalent.

2.4 Asset Performance Indicators

2.4.1 Indicator Background

There are three nationally-recognised carriageway condition indicators and one relating to footways, which is discussed in more detail in the footway section of this report. All four were formerly Best Value Performance Indicators (BVPIs); under the new system of National Indicators (NIs) only the two relating to ‘A roads’ and ‘B & C roads’ have been retained in the national indicator set although Hertfordshire continues to measure and report of the ‘U road’ and ‘Busy footway’ indicators as well, since these were target measures in both the Local Transport Plan and Corporate Plan.

In each case the indicator relates to the proportion of the asset that is in a relatively poor condition (although the definition of ‘poor’ is not the same for all indicators). Consequently a lower result is better and a declining score indicates an ongoing improvement in the condition of the asset.


NI 168 measures the condition of A roads and has previously been known as both BV96 and BV223

NI 169 measures the condition of B&C roads and has previously been known as both BV97a and BV224a

The condition measure for U (unclassified) roads was previously known as both BV97a and BV224a

The condition measure for busy footways was known as BV187

2.4.2 Regional and National Comparisons

The three graphs below put the Hertfordshire PIs into context in comparison to the regional and national averages, although the national average for 2008/09 is not yet available.

The A road and B&C road PIs are both measured using the machine based SCANNER

survey. The weighting set that defines the relative importance of different types of defect in determining the score was changed significantly for 2007/08, resulting in a substantial drop in these indicators. This drop


A Road PI Comparisons

0

2

4

6

8

10

12

14

2005/06 2006/07 2007/08 2008/09

A Herts

A East

A National

B&C Road PI Comparisons

0

5

10

15

20

2005/06 2006/07 2007/08 2008/09

BC Herts

BC East

BC National

U Road PI Comparisons

0

5

10

15

20

25

2005/06 2006/07 2007/08 2008/09

U Herts

U East

U National

15

was mirrored by both the regional and national averages. A further change was implemented for 2008/09, which has had the effect of increasing both the Hertfordshire scores and the regional averages. This is a significant contributory factor in the fluctuation of this indicator.

The U roads are surveyed using a different technique and, as they are no longer considered a national indicator, the rules and weightings have not been changed for several years, helping the indicator to remain more stable.

These trends and issues are discussed in more detail in the next section.

2.4.3 Carriageway Performance

The last three years have seen steady year-on-year improvements in the three carriageway indicators, however 2008/09 saw all three worsen slightly.

There are a number of different factors that could potentially cause this, either individually or in combination:

Deterioration of the asset Rounding effects on the PI values Data collection methods Data processing methods

2.4.3.1 Deterioration of the asset

Recent years have seen improvements in condition, thanks in no small part to significant additional investment in the asset through Herts Highways and Highways Extra. However, condition projections have consistently shown that the underlying ‘baseline’ funding alone was not sufficient to sustain the asset in steady state and projected a slow but steady worsening of condition.

For this reason the condition targets, which were based around a funding scenario in which enhanced funding did not continue indefinitely, were set to show a slight deterioration over time. Consequently the PIs are still at or below target, despite the worsening this year.

It is likely that genuine natural deterioration accounts for some of the change in the PI values this year. The surveys for the A, B and C roads were completed before the worst of the winter and therefore the exceptional winter damage will not be the cause of this deterioration. The U road surveys were underway at the time of the February snow and some of the surveys were completed after it had cleared although this is a relatively small proportion of the surveys. It is therefore likely that the snow in December and January (and, to a lesser extent, February) had an additional impact on the U road PI, in addition to the normal annual deterioration.

It should be kept in mind that the deterioration not captured by this year’s surveys will show up next year (unless addressed first); consequently we may expect to see further deterioration-based worsening of the PIs next year, even if this winter is relatively mild. This is considered further later in this report.

2.4.3.2 Rounding Effects on PI Values


The PIs are now all reported as whole numbers rather than to one or more decimal places as was the case in the early years of these measures.Because the numbers themselves are small absolute values, the effect of rounding to a whole number can distort the result significantly.

For instance a result of 5.5 and 6.4 would both round to 6. This effect is more pronounced the smaller the indicator number is in absolute terms. While this effect on its own cannot generate an increase in PI number, it can magnify a small increase disproportionately.

However, in this particular case, the effect of rounding up or down is relatively minor and has not made a large contribution to the change in PI values.

2.4.3.3 Data Collection Methods

Condition data for the A, B and C roads is collected using an automated process called SCANNER while the surveys for the U roads are carried out via a visual inspection.

Since the visual data is relatively subjective and therefore potentially most variable, HCC have retained the same survey company for the U roads in order to keep the data as consistent as possible from year to year. Even this does not guarantee completely consistent data from year to year however. With any visual survey, prevailing conditions can influence how much the inspectors see and record; for instance fine cracks in the road surface are most visible when the road is drying since the water stays in the cracks longer than it does on the surface, making them darker and more obvious.Consequently survey results, even averaged over the whole network will show variations from year to year, especially if survey conditions are notably different.

The machine-based SCANNER data offers greater repeatability but it is still not perfect and a degree of variance is almost inevitable. In addition, due to the results of tendering processes, we have had several different SCANNER providers in the last few years. The machines and operators are calibrated and certified independently to ensure that they are as comparable as possible but, again, some degree of variance is almost inevitable.

2.4.3.4 Data Processing Methods

The condition surveys are processed through a UKPMS (UK Pavement Management System) module. This takes a national set of rules and parameters and applies them to our data to come up with the PI results as well as other information useful in the management of the network.

These rules and parameters are changed from time to time as the processes are refined and the weighting or importance of different factors is reassessed. This can result in a significant shift in the indicator value, a considerable source of frustration to local authorities since it makes valid year-on-year comparisons much more difficult.

There was a major change in relative weightings for 2007/08 which saw the values for the two SCANNER surveys (A roads and B&C roads) drop


significantly as a result. There was another change for 2008/09 which saw the values rise, although not by as much as they had dropped the previous year.

In order to do a fair and consistent comparison, Hertfordshire has recalculated the A road indicators for 2007/08 and 2008/09 using the rules and weightings for 2006/07, in order to take the methodology changes out of the equation. These results are shown in the graph below and demonstrate a much more stable indicator.

A Road PI - Comparison Using Different Rules

0123456789

2006/07 2007/08 2008/09

As reported

Consistent rules

As the graph shows, when the same rules set is used for the last three years, the year-on-year change is modest and probably reflects minor fluctuations in the data as well as genuine changes in the condition of the network as roads deteriorate and are maintained or repaired. The picture for the B&C roads is similar.

2.4.3.5 Performance Data Conclusions

It is likely that changes in weightings in the last two years have had a much bigger influence on annual changes in the A road and B&C road indicators than actual changes in condition. Unfortunately, for reporting purposes, we have to use the official weightings but we can revert to consistent data processing methods in order to derive better year-on-year comparisons.

That said, there will always be minor fluctuations in data from year to year and it is more meaningful to look at a general trend over several years rather than read too much into a small fluctuation in a single year.

We can therefore conclude that, in each of the three broad categories of carriageways, there has been a small rise in the condition indicator value this year, corresponding to a slight worsening of overall condition. While this is in line with previous predictions the condition would deteriorate slowly once the enhanced investment stopped, it was anticipated that this would take a year or two longer to start to manifest. These changes may, therefore, be related to inevitable minor annual fluctuations in the data since each change is 1% or less when changes in data processing rules are taken into account.

The longer term trend for each of these indicators is still, for the moment, downwards (i.e. improving) and we will have a clearer idea as to whether


these indicators are stabilising or deteriorating once the 2009/10 results are available in the spring of 2010.

2.5 Programme Delivery 2008/09

The table below summarises the quantity and value of carriageway schemes delivered under the Integrated Works Programme (IWP) during 2008/09:Scheme / Project Name Total Costs Approx. Length (m)Principal Roads (£000’s) A Road Surface Dressing £1,337 21,500A Road Surfacing £5,803 16,100A Road Reconstruction £429 1,000Total £7,569 38,600 Local Roads - Carriageway Local C/way Surface Dressing £3,580 141,500Local C/way Micro-Asphalt / Thin Surfacing £2,635 57,400Local C/way Surfacing £2,577 14,800Local C/way Recon. / Recycling £1,045 6,700Total £9,837 220,400

2.6 Programme Planned for 2009/10

The table below summarises the quantity and value of carriageway schemes intended for delivery under the IWP during the current year 2009/10:Scheme / Project Name Total Costs Estimated Length (m)Principal Roads (£000’s) A Road Surface Dressing £1,262 20,600A Road Surfacing £4,126 11,400A10 Turnford, Major Reconstruction £808 550Total £6,196 32,550 Local Roads - Carriageway Local C/way Surface Dressing £3,856 145,800Local C/way Micro-Asphalt £1,884 41,000Local C/way Surfacing / Recycling £2,786 17,200Total £8,526 204,000

Winter Recovery ProgrammeC/way Winter Recovery £3,912 55,700

Notes: The surface dressing programme in 09/10 includes several schemes with

substantial preparation or ancillary costs such as drainage or culvert repairs totalling around £300,000. These costs are included in the SD programme numbers above.

The Winter Recovery Programme covers a number of A roads and local roads adversely affected by the severe weather in February 2009 and includes works of various different types.


Many of the schemes planned for 09/10 increased in cost as a result of the winter damage as schemes required more preparation work or a more substantial treatment than when initially assessed.

2.7 Future Projections and Options

2.7.1 Headlines

2.7.1.1 A Roads Worsen gradually under Preferred Cash Flow (PCF), more rapidly if

funding is decreased further. NI worsen from 6% to 12% by 2020 under PCF Each £1m removed from ARP below PCF increases this by rate by 20-

25% relative (so zero spend takes NI to circa 25% by ‘20)

2.7.1.2 B, C & U Roads B&C predict close to steady state under PCF U roads on their own and B, C & U roads combined worsen gradually

under PCF, more rapidly if funding is decreased further. NI 168 for B&C worsens from 9% to around 12% by 2020 under PCF,

mostly at the expense of U roads Each £2m removed from local roads below PCF increases this by rate by

20-25% relative

2.7.2 Caveats to Condition and Performance Forecasts

Condition data - much of the condition data predates the winter snow and is therefore optimistic.

Strategy – the condition predictions are based on the assumption that we continue to use an optimised asset management strategy as far as possible for the bulk of the IWP work, as we have over the past few years. If Members choose to direct the strategy differently (for instance moving to a more locality-based allocation process or placing limits on certain programmes such as reducing surface dressing in favour of more urban treatments) then the projections on which these predictions are based will be optimistic.

2.7.2 Budgets

The works costs in the carriageway deterioration model (which is discussed in more detail later) are uplifted each year to reflect inflation increases and other pressures, such as the increase of restricted working caused by the TMA, which has had a noticeable impact on the overall cost of works programmes.

For the purposes of this analysis the Preferred Cash Flow (PCF) has been used as the baseline scenario with additions or reductions being relative.

In addition to the IWP schemes, Herts Highway has also delivers a “Super Cat 2” programme of small, locally prioritised schemes designed to fix problems too large for the Cat.2 programme that do not feature on the IWP. The condition projections include an estimate of the contribution that the Super


Cat 2 programmes might make to future condition, although it is accepted that these are non-optimised and will not, therefore, make a full contribution.

2.7.3 Future Predictions – A Roads

On current PCF scenario the NI value is predicted to double over the next 10-12 years from around 6% in 08/09 to 12% in 2020/21. This potential trend is in line with the worsening of this indicator seen this year. Although small (in absolute terms) fluctuations like this on an indicator which is, in itself, a small number should be treated with caution and a trend over several years is a more reliable indicator.

The initial impact of this will be small – between 07/08 and 08/09 we have seen a small percentage drift from amber to red as our rate of preventative and corrective works falls behind the rate of deterioration. Note that the 08/09 A road surveys were done in the autumn of 2008, well before most of the winter’s snow. We should expect a further worsening when this year’s surveys are undertaken as a result, even if this year is comparatively mild.

The impact on the 10/11 results of different funding scenarios is likely to be limited. Many of the benefits of previous year’s preventative works will continue to accrue and the difference in a given year between the PCF and ‘do nothing’ is slim; the impacts of these changes will be seen several years down the line when the impact of a lack of earlier investment will manifest.

Add to this the fact that the indicator is rounded to a whole number and it will be seen that a comparatively large relative change could be masked by the rounding.

It is likely that the A road indicator will continue to worsen slowly and that the impact of last winter will take it to 7% next year; it is unlikely to improve significantly the following year unless significant additional money over and above the PCF is invested during 2010/11. Reducing the budgets below the PCF is unlikely to have an large in-year impact on the indicator although the long term impacts will be significant. In broad terms reducing the investment to zero will double the projected deterioration over the next 10-12 years so, in crude terms, for every £1m we remove from the A road programme we would expect the rate of worsening to increase by 20-25%

2.7.4 Future Predictions - B, C & U Roads

B&C roads are predicted to hold very close to steady state under PCF. However, B, C and U are modelled together and B&C tend to have priority due to the higher traffic flows and consequent greater benefits of them being maintained in good condition. Hence the B&C roads will tend to be maintained at the expense of U roads.

Making cuts further into the B/C/U pot would, consequently, fall first on U roads unless the strategy was changed to prevent this.


Looking at B, C and U combined; PCF shows steady deterioration into the future. In the long term the ‘do nothing scenario’ sees the condition fall about twice as fast as the baseline scenario. Consequently we can estimate that each £2m removed from the PCF on these roads would hasten the deterioration by about 20-25% relative.

As with A roads, rounding factors in the NI calculations and the small absolute value of the number means that single year fluctuations may be masked.

2.8 Carriageway Strategy and Objectives

The IWP carriageway maintenance programme is a strategic programme that aims to maintain Hertfordshire's carriageway asset. When considering this in more detail, the first question that needs to be considered is “what are our Strategic Objectives for this programme?”

2.8.1 Strategic Objectives

The strategic objectives of the programme are twofold: maintain the roads to an appropriate standard to provide a suitable

service to all road users

do so in a way that delivers the best long term value for money

There are some key phrases in these objectives that bear further consideration:

Appropriate standard – This needs to take into account the nature of the road and the use to which it is normally put. The appropriate standard may well vary from road to road depending on these factors but the key point is making sure that the road is fit for purpose. That is not to say that the road needs to be 'as new' or even defect-free but the road needs to be suitable for normal use.

Suitable service – again this stresses the need to consider fitness for purpose. A road that is maintained in pristine condition at all times is unlikely to be providing a suitable service since the costs associated with this may well be prohibitive or, at least, unsustainable. The issue of levels of service and appropriate intervention points will be considered in more detail in other documents in the TAMP family.

All road users – this indicates that the service should consider the needs of all groups of people that will typically be using the road including, where appropriate: vehicle drivers, cyclists and motor cyclists, pedestrians and equestrians, local residents, buses etc. Some users will fall into more than one group and there will sometimes need to be compromises between different groups. Such compromises should be guided by the road hierarchy and the use to which it is normally put and informed by other appropriate strategies and policies.

Best long-term value for money – Value for money is a cornerstone of the asset management approach and, with budget pressures likely for the foreseeable future, it is more important than ever that we extract


the best possible value for the available budgets. However, it is equally important that we look at and understand the long-term implications of the strategies that we consider. An approach that delivers short term benefits at the expense of higher long term costs (or poorer long-term levels of service) is unlikely to be an acceptable or sustainable option.

2.8.2 Strategic Targets

As discussed earlier in this report, there are a number of strategic targets related to the various performance indicators for the carriageway asset.

The performance indicators show that the asset condition has improved over the last few years as a result of additional investment, but has deteriorated very slightly this year for the first time in a number of years. The PI targets allow for a slight reduction in condition in future years, so we are still within the projected targets that we set for ourselves a few years ago.

With further substantial additional investment unlikely in the immediate future, our strategy is likely to need to focus on keeping the network as close to 'steady state' in terms of condition as possible within the budget available. The approach, however, is flexible and if, at some future point, additional investment becomes available with the objective of improving condition, then the strategy is equally capable of delivering alternative strategies.These targets are for the network as a whole, not for individual roads. Roads naturally deteriorate over the course of a life cycle. Individual roads will therefore deteriorate over time until such time as a maintenance treatment is applied. Consequently, at the moment, we have not set a minimum condition below which a particular road will not be allowed to fall except that the road needs to be kept safe and fit for purpose, potentially through Category 1 or other localised treatments. More work is being done on levels of service in other documents in the TAMP family.

2.8.3 Carriageway Strategies

With the strategic objectives set out, we can then consider the strategy needed to deliver those objectives. There are two different approaches we might consider, depending on the constraints on the programme at the time:

A) Deliver the best possible level of service within the available budgetB) Deliver a defined level of service for the lowest whole life cost

Given the aforementioned pressures on budgets, it is likely that, for the foreseeable future at least, the available budget will be the limiting factor on our strategy and we will therefore be following Approach A - aiming to come as close as possible to delivering steady state (in which the overall condition of the network does not decline) within the available budgets.

If, in the future, funding were to increase to the point where we could potentially exceed steady state and make further improvements in condition, then we would face the choice of either delivering steady state for the minimum necessary funding (Approach B) or delivering as much of an improvement as possible with the available funding (a variant on Approach A).


In such a situation the choice between these two approaches would properly be made by budget decision makers.

Under the current budget scenario, however, we will be looking to maintain the network as close as possible to current condition in the long term within the available budgets. We can therefore summarise the strategy as:

Prioritise the available resources - taking into account user needs, hierarchy and the nature of the road - to maintain the condition of the

network as a whole as close to steady state as possible by delivering a programme of works designed to optimise long term value for money.

In order to help deliver this strategy, Hertfordshire uses an innovative computer-based deterioration model that helps to predict future need and provides a starting point for our programmes. The use of this model was the core of our ‘Element 2’ submission to the DfT, discussed in more detail in section 1, for which we were awarded £500,000.

2.9 Deterioration Modelling

The objective of the deterioration modelling process is to help us deliver the strategy outlined above. It should be stressed that the model is a tool to help deliver the strategy, not an end in itself.

2.9.1 What is the Deterioration Model?

The deterioration model (the model) is a computerised tool that performs several key functions:

predicts the future deterioration of each section of road uses that predicted performance to suggest the most appropriate

options and timing for future maintenance treatments prepares a suggested optimised programme of works to deliver the

best value for the available money helps predict future performance trends based on different budget

scenarios

To do this, the model uses condition information from our annual condition surveys and information on the construction of the road and the number of reported defects from our highway database. It also considers information such as the road hierarchy, the level of traffic that uses the road and whether it is a bus route or has a significant number of HGVs.

2.9.2 What are the Key Drivers in the Model?

The key factors considered by the model are: Benefit (improved condition, now and future)Cost of the proposed treatment strategyCost of 'do nothing' based on Cat.1 etcTraffic levels on the road

The model is also influenced by the following factors, which may limit our choice of strategies and therefore influence the Benefit/Cost equation:


Classification and hierarchyUrban or ruralBus routesHGV route or industrial areaRoundabout

Of these, Benefit and Cost are the biggest impacts but the relationship between the various factors is complex. The following sections are intended to give a flavour for how the calculations are shaped.

2.9.3 Calculating the Benefit

The model will test a number of different strategies for each road section; each strategy is a treatment option. This could be a single treatment or a series of successive treatments over a period of years. It could also be ‘Do Nothing’, a scenario which is always considered as it s used as a baseline against which the other scenarios are tested.

The model uses optimisation to select the best treatment strategy. The process seeks to minimise the Average Condition Index (ACI) for the network for the available funds. The ACI is discussed in more detail later.

To decide between the relative merits of each strategy, the model uses a Benefit-Cost (BC) analysis. The BC is used to rank strategies for the entire network, selecting strategies with the highest BC until the budget level is reached. In this way the suggested programme delivers the maximum possible long-term benefit for the available budget.

Strategy costs are calculated based upon the cost of individual treatments, discounted to a present value cost over the analysis life cycle using a 6% discount rate. This encourages the model to select a later treatment over an earlier one if the benefits of the two are similar.

Strategy benefits are calculated as the improvement, as measured by the ACI, between the ‘Do Nothing’ and Improvement strategy (see Figure 2.9 below). To account for the relative importance of each road section, benefits are weighted by traffic.

Benefit = AUCBenefit × AADT1/3

Where AUC is the Area-Under-Curve (as illustrated here) and AADT is the Annual Average Daily Traffic, which is a standard measure of traffic flows.

From this is it will be seen that the Benefit depends on the


improvement in condition (both now and in the future) and on the level of traffic using the road.

Figure 2.9 Conceptual Strategy Benefits2.9.4 Traffic Loading

The benefit calculation is weighted by the traffic loading on the road. This will tend to make the model favour busier roads for work over those more lightly-trafficked.

This weighting means that the roads used by the most people are given a degree of priority and helps to ensure Hertfordshire’s economic wellbeing by maintaining key routes. It also helps to manage risk effectively by reducing the likelihood of defects on busier roads. In addition to these considerations, heavily-trafficked roads are, almost always, more difficult and expensive to repair or rebuild should they be allowed to fail. Therefore the long-term consequences and costs of failing to maintain the busier roads would be greater than the impact on less trafficked roads. Ultimately the impact and costs associated with these long-term choices will be borne by residents and businesses of Hertfordshire, for whom the County Council is custodian of the highway network. Therefore, in line with the strategy discussed above, we aim to target the available funds to give the best long term benefits and to minimise the long term liabilities.

However, using the AADT ‘as is’ would be disproportionate, since the busiest roads carry around 200 times the traffic of the quietest ones and all need to be considered fairly. For this reason we use AADT1/3 or the ‘cube root’ of the AADT, rather than the unadjusted number. This means that, while traffic load has an effect, it does not dominate the whole calculation.

For instance, consider two similar treatments that offer the same AUC benefit on two adjacent roads. The first road carries 1,000 vehicles per day and the second carries 10,000. After adjusting for traffic, the Benefit from doing the busier road will be considered to be 2.15 times the Benefit on the quieter road (rather than ten times as it would be if the straight AADT were used).

Traffic data is an area we are still improving. Hertfordshire does not have detailed traffic counts for every road section and (with around 18,000 road sections) it would not be viable to do counts on them all. We currently use actual traffic data where available and estimates, based on typical values for roads of that type, hierarchy and area. We hope to improve the estimates further in the future with the use of a number of traffic models currently under development although, given the way traffic is used, small changes in estimated traffic levels will not make a large difference to the calculated Benefit.

2.9.5 Calculating Costs

Cost information looks at the cost of the proposed strategy vs. the ‘do nothing’ cost. The costs used for treatments are based on the typical actual costs of doing the type of work in question. These costs scale according to the size of the job and also take into account existing defects where necessary. For instance if a surface treatment is suggested then an appropriate amount is added on to allow for any necessary preparation works such as patching,


based on the condition survey information. Consequently the cost estimate will vary from site to site but a general feel for the typical costs is given below.

Typical costs A Roads

Other Roads

Description

Surface Dressing

£8.50 per m2

£5.50 per m2

Surface treatment mostly used on rural roads or roads without on-street parking

Micro Asphalt N/A £8.50 per m2

Surface treatment mostly used on less-busy urban roads

Resurfacing £30-60 per m2

£15-40 per m2

Replacing the existing road surface and sometimes the underlying layers

Reconstruction or recycling

£100+ per m2

£25-30 per m2

Replacing the surface and renewing or repairing the structural layers underneath

In addition to scheme costs, the model also calculates the likely ongoing and future costs of pothole repairs and other similar works to provide a cost for the ‘Do Nothing’ scenario.

This is important as it means that schemes can be triggered on roads in a poor condition in order to head off high reactive costs in the future.

The calculation of these ongoing reactive costs uses information on the number of potholes dealt with on the road in question from Hertfordshire’s highway database and also considers defects identified on the condition surveys, such as cracking, that may lead to an increase in the rate of formation of potholes in the future.

2.9.6 Restricted Options

There are a number of options that are restricted in the model because engineering experience tells us that these are unlikely to be suitable on certain types of roads.

The model is restricted to suggesting surface dressing on roads that are considered Rural, which, for these purposes is normally defined as having a speed limit greater than 40mph.

The reason for this is that, due to the nature of surface dressing, the new surface can be damaged by cars parking on it, especially if that parking requires a lot of manoeuvring. However, many urban distributor roads are suitable for surface dressing and our engineers consider this option where appropriate as part of the design process. For 2010 nearly half of the surface dressing sites will be at least partly urban in character, as the table below shows. With this in mind we may consider revising the restrictions on the model in future years.

We also do not allow the model to suggest a micro asphalt treatment on roads that carry high volumes of traffic, particularly HGVs, or on roundabouts since the high stresses on sites like this can damage the surface while it is new and cause it to fail. For this reason micro asphalt is not an option for the model on


A roads, roundabouts and certain other roads identified as carrying significant numbers of heavy vehicles.

Summary of Number of Sites Whole or Part Surface Dressed in More Built up AreasSEASON Total

SitesVillage Roads

Housing Estate Roads

Housing Estate

Feeders

Urban + Village A

Roads

Total In More Built Up Areas

% of Total Schemes

2006 33 0 0 0 0 0 0

2007 139 16 1 2 3 22 16%

2008 126 21 3 3 3 30 24%

2009 171 22 3* 12 7 44 26%

2010** 106 22 18 11 1 52 49%

TOTAL 575 81 22 28 14 148 26%

*Two of these sites were whole small estates not just individual roads**Provisional

2.9.7 Does the Model Produce a Particular Bias?

The only deliberate and intentional bias in the model is towards the solution that offers the highest Benefit/Cost ratio – in other words the one that delivers the best long term value for money.

It has been suggested that there is a bias towards rural roads because of surface dressing and the restrictions on its use.

It is certainly true that surface dressing frequently offers good value and, under current model rules, can old be suggested in rural areas. This gives rural roads a head start on the value calculation but other factors such as traffic volumes will tend to influence the model in the direction of urban roads.

The two graphs below show the urban/rural split of schemes suggested by the model for future years under two different budget scenarios. The year (along the bottom axis) starts at year 3 (2011/12) because this is the first year of the current programme in which the model output has not yet been altered by choices made during the consultation process. Years 1 and 2 (2009/10 and 2010/11) have been subject to change due to such consultations and are therefore omitted for clarity to allow focus on the model.


The first graph shows Budget Scenario (BS) 1, a typical spend scenario. The second shows BS5, an enhanced spend scenario. The proportion of urban and rural works suggested varies significantly from year to year in both scenarios although, with more money, BS5 tends to increase the proportion of urban work slightly.

In previous years the split has similarly varied. In the last few years we have done a significant amount of surface dressing, the majority of which was on rural roads. In part this represented the model selecting ‘quick wins’ – sites that could be surface dressed and offered good value for money. Although the model continues to suggest surface dressing sites, the trend for the medium term is more towards urban treatments. Part of the increase in rural treatments towards the end of the ten-year period on the above graphs around 2016 is likely to represent repeat treatments on sites surface dressed from 2006 onwards since the normal frequency for surface dressing is around 8 to 12 years.

It should also be noted that, for good engineering reasons, we carry out preparatory works in one year and then apply the surface dressing in the spring/summer of the following year. For this reason surface dressing schemes always appear twice in the IWP, once in the preparation year and


once in the dressing year. This doubles the apparent number of surface dressing schemes on the programme (without actually increasing the number of sites surface dressed), which may help to create the perception that more sites are surface dressed than is actually the case.

In order to look at the shape of the future programme, we have analysed the current IWP and FWP along with the model’s suggested programme out to 2018/19 to create a ten-year view of how the model’s suggestions are distributed across the network.

The graph below shows a split of the ten year programme divided by the road hierarchies and urban/rural. For each category it shows the total number of sites on the programme, the projected cost of those sites (expressed in units of £100,000) and the total area of the road that would be treated (expressed in units of 1,000,000 sq m).

A U

rban

A R

ural

B U

rban

B R

ural

C U

rban

C R

ural

U U

rban

U R

ural

No. SitesArea0

500

1000

1500

2000

2500

Quantity

Road Category

Ten Year Programme Comparison

No. SitesCostArea

The following graph looks at the distribution of proposed sites in more detail.

Ten Year Programme - Works Split by No. of Sites

A UrbanA Rural

B UrbanB RuralC Urban

C RuralU Urban

U Rural

This graph does the same for area of works


Ten Year Programme - Works Split by Area (sq m)

A UrbanA Rural

B Urban

B RuralC UrbanC Rural

U UrbanU Rural

This graph looks at the split of costs.

Ten Year Programme - Works Split by Cost

A UrbanA Rural

B UrbanB RuralC Urban

C RuralU Urban

U Rural

From these graphs we can draw the following conclusions: The majority of sites are on unclassified roads with urban

unclassified roads being the largest group by some distance. In terms of the (square metre) areas to be treated, the three largest

groups are U roads (urban and rural) and rural C roads. Looking at the how the available money might split across

categories, Urban A roads are the largest single group, followed by Urban U roads.

In order to judge whether this split is reasonable, we need to look at the urban/rural split in context.

The following graph looks at how the whole of the county’s network divides up on length and width and how the model suggests funding should be divided. By length 68% of the roads are urban, 70% by area and the model split puts 71% of the available budget into urban roads.


0%

20%

40%

60%

80%

100%

length area spend

Whole Network - Urban and Rural Proportions

RuralUrban

There are, however, variations within individual parts of the network. The graph below shows the same information for the A roads alone and shows that a greater proportion of the potential spend is targeted on urban roads,

despite the fact that they are less than half the network. In part this is due to the wider availability of cheaper treatments like surface dressing for the rural A roads.

The next graph shows the same splits for B&C roads and, again, the pattern is similar to that in the A roads with the urban roads getting a slightly disproportionate share of the available funding.

The final graph shows the slit on the U roads and here the picture is reversed with the rural U roads getting slightly more than an even pro rate split would suggest and the urban roads correspondingly less.


0%

20%

40%

60%

80%

100%

length area spend

A roads - Urban and Rural Proportions

RuralUrban

0%

20%

40%

60%

80%

100%

length area spend

B&C roads - Urban and Rural Proportions

Rural

Urban

32

In order to look at this in more detail, we need to divide the U roads in to those that carry a relatively low level of traffic – less than 700 vehicles per day – and those that carry a level of traffic higher than that.The graph below shows the U road data split on that basis. The higher traffic roads are considered to deliver a relatively greater benefit and the rural roads have the advantage of cheaper treatments so it is perhaps not surprising that it is the low traffic urban U roads that receive the smallest relative proportion of the available funding.

0%

20%

40%

60%

80%

100%

Length Area Spend

U Roads - Urban, Rural, Low and Higher Traffic

Higher Traffic Rural

Low Traffic RuralHigher Traffic UrbanLow Traffic Urban

Given the previous discussion about the weightings within the model, this is not a surprise. This analysis is all based on the basic level of budgets without any enhanced investment and, as the projections elsewhere in this section suggest, that budget level is not sufficient to fully maintain the network in its current condition. There are consequently some tough choices to be made and, based on the constraints give to it, the low-traffic urban unclassified roads offer relatively poor value for money and therefore see the lowest relative level of investment.

As the first two graphs in this section (BS1 and BS05) show, if investment is increased the additional money tends to be directed more towards urban areas and this will progressively start to target more of these low traffic urban unclassified roads but, in a financially-constrained scenario, these are the


0%

20%

40%

60%

80%

100%

length area spend

U roads - Urban and Rural Proportions

Rural

Urban

33

roads that offer the least value for money based on the current balance within the model.

That balance takes into account current and future costs and quantified benefits around improved condition, with a preference for busier roads. However it does not currently take into account other factors such as aesthetics or the street scene benefit of improving the roads where people live.

So the answer to the question is that there are several identifiable trends within the programme that the model produces.

High traffic roads fare better Rural roads have a slight advantage due to the cheaper treatment

costs Both of these factors are most noticeable when there are

insufficient funds to do all the work the model would like to promote


2.10 Average Condition Index (ACI)

The main national condition measures, discussed in Section 3, above, are the various NIs (previously BVPIs). While these give a nationally-comparable result, Hertfordshire has long realised that the indicators are flawed.

The NI-style headline indicators are a relatively coarse measure of the proportion of roads of a particular type that ‘should be considered for maintenance’ (or, in other words are in ‘poor’ condition). This is defined by the number of roads that are over an arbitrary threshold. While more detailed information is available, the reported headline number is therefore a simple percentage. The system does not consider how bad the poor roads are, nor does it take any count of roads that are not yet poor – such roads could be brand new or almost poor, it makes no difference to the headline indicator.

This causes two related problems. Firstly there is a temptation amongst asset managers and decision makers to ‘chase’ the indicator – to target roads that are in the poor category for works regardless of whether it is the optimum time to treat them or not. Secondly, and more significantly, the indicator does not recognise the benefits of treating roads that are not yet poor - work done on such roads will have no immediate impact on the headline indicator. The end result of this is that there is no incentive to carry out preventative maintenance since the NIs do not reflect the benefits of such works.

To better reflect the impact of our asset management strategy, Hertfordshire developed the Average Condition Index (or ACI) which gives a more balanced view of network condition.

As the name implies, the ACI looks at average condition – it is used in the model on a road-by-road basis to help determine the efficiency of schemes and can be used at a network level as an alternative to the NIs. For each road or part of the network, the model assesses the total level of defects and expresses it on a scale that runs from 0 (defect free) to 100 (failed). This is not a true percentage but has been scaled to run from 0 to 100 for ease of comparison.

2.10.1 Key Distresses in Average Condition Index

Inspections of pavement sections requiring maintenance during 2005 identified the following drivers for undertaking a programmed maintenance treatment on B&C and U class roads:

Category 1: Unplanned Reactive Maintenance – Potholes Category 2: Planned Reactive Maintenance – Isolated pavement

Repairs Extent of potholes repaired and observed Cracking, including Major and Transverse types Surface Deterioration Edge Faults Pavement Settlement/Subsidence (to a lesser extent).


From 2007 classified roads have SCANNER data. Given the state of pavement data it was decided to no longer include pavement residual life. This measure can be inferred from Longitudinal Profile Variance (LV10) and rutting and therefore the motivations for treatments of classified roads have been identified as:

Cracking 3m Longitudinal profile variance 10m Longitudinal profile variance Rutting.

2.10.2 Classified Roads

The Average Condition Index (ACI) for classified roads (A, B and C) only includes SCANNER data. Therefore for the ACI calculation is:

ACI = MIN(100, Cracking × 2.5 + LPV3 × 0.5 + LPV10 × 0.05 + Mean Rut Depth × 0.5)

Where

Cracking = The extent of cracking as a percentage of the pavement area

LPV3 = = 3m Longitudinal Profile VarianceLPV10 = 10m Longitudinal Profile VarianceMean Rut Depth = Mean Rutting Depth for the pavement

section (mm).

2.10.3 Unclassified Roads

For unclassified (U) roads Coarse Visual Inspection (CVI) data is used as SCANNER data is not available.

ACI = ƒ(Cracking, Surface Deterioration, Edge Fault, Potholes, Patches)

Where

Cracking = The extent of cracking as a percentage of pavement area

Surface Deterioration = The extent of surface deterioration as a percentage of pavement area

Edge Fault = The extent of edge fault as a percentage of total pavement edge

Potholes = The extent of potholes as a percentage of pavement area

Patches = The extent of pothole patches (Category 1 repairs) as a percentage of pavement area

After considering several forms for the Index the following relationship was selected:


HCC Objective Index = Min(100, Cracking2/3 + Surface Deterioration2/3 + (0.5 × Edge Fault)2/3 + Min(100,10 × (Potholes + Patches))2/3)3/2 / 1.75

The power function used within the index gives a relatively higher score for more highly distressed sections of pavement. In other words the relationship is not linear. The divisor (1.75) scales the result so that it operates in a range of 0 to 100.

2.10.4 ACI Results

2.10.4.1 A Roads

The graph below shows the historic performance of the ACI over the last few years with additional investment improving the indicator. The ‘committed’ section shows the predicted performance based on the current committed IWP programme while the forecast shows the likely performance in the future under different budget scenarios.

As with the NI predictions, the model is suggesting that significant extra investment is needed in the A road network in order to maintain its condition.

A Roads - Investment Options

0

5

10

15

20

25

30

2007/08 2008/09 2009/10 2010/11 2011/12 2012/13 2013/14 2014/15 2015/16 2016/17 2017/18 2018/19 2019/20 2020/21 2021/22 2022/23 2023/24

Year

AC

I

Base - £4.3M paBase + £1M paBase + £2M paBase + £3M paBase + £5M paBase + £10M paBase + £10M Yr 3Base + £20M Yr 3-5

His

toric

Com

mitt

ed

Fore

cast

2.10.4.2 B&C Roads


The graph below shows the same information for the B&C roads and trend is similar to the A roads with historic improvements due to recent investment but predicted future deterioration.

2.10.4.3 U Roads

The final graph shows the trend and predictions for unclassified roads. Again recent investment in the network is highlighted, together with the potential future performance under a variety of investment scenarios.


Non-Principal Classified Roads - B&C - Change in ACI

0

5

10

15

20

25

30

35

40

2007

/08

2008

/09

2009

/10

2010

/11

2011

/12

2012

/13

2013

/14

2014

/15

2015

/16

2016

/17

2017

/18

2018

/19

Year

Aver

age

Valu

e (W

eigh

ted

by L

engt

h)

No Investment

Base Investment

Base + £3.75M p.a.

Base + £7.50M p.a.

Worst First

His

toric Fo

reca

st

U Roads Only

0

5

10

15

20

25

30

2007/082008/092009/102010/112011/122012/132013/142014/152015/162016/172017/182018/192019/202020/212021/222022/232023/24Year

AC

I

Base Base + £10M Yr3-5 + £7.5M elseBase + £20M Yr3-5 + £4M elseBase + £30M Yr3-5 + £1.2M elseBase + £30M Yr3-4 + £4M elseBase + £20M Yr3-4 + £6M else

His

toric

Com

mitt

ed

Fore

cast

38

2 Drainage

3.1 Pitt Review and Flood and Water Bill

Following the summer floods of 2007, the government asked Sir Michael Pitt to undertake an in-depth independent review of the floods. The review’s final report was published on 25th June 2008 and contained 92 recommendations to improve flood risk management, many of which are applicable to local authorities. The most pertinent include:

15. Local authorities should positively tackle local problems of flooding by working with all relevant parties, establishing ownership and legal responsibility.

16. Local authorities should collate and map the main flood risk management and drainage assets (over and underground), including a record of their ownership and condition.

19. Local authorities should assess and, if appropriate, enhance their technical capabilities to deliver a wide range of responsibilities in relation to local flood risk management.

As part of their response to the ‘Pitt Review’, the Government has produced the draft Floods and Water Management Bill, which after consultation has recently been introduced into Parliament. The purpose of the bill is to improve the management of flood risk and coastal erosion, no doubt exacerbated by climate change.

The draft Bill proposes that responsibility for management of flood risk relating to coasts and main rivers will remain with the Environment Agency (EA) and that local authorities (Unitary Authorities and County Councils) will lead the coordination of flood risk management relating to all other forms of flooding. This will include:

Surface water flooding – run-off from rainfall before it enters drains and watercourses.

Flooding from ordinary water courses – ditches, streams and channels that are not designated as Main Rivers.

Groundwater flooding – for example from the emergence of springs or a local rise in the water table.

Clearly this might have a significant impact on the role of Herts Highways and the County Council as a whole. We will continue to track the Bill and report on its implications as appropriate although some early action measures are already being taken in advance of the Bill passing in to law, as discussed below.

3.2 NETSWA and Surface Water Management Plans (SWMP)In response to the recommendations of the Pitt Report (particularly no 15 above) and in advance of the enactment of the “Flood and Water Management Bill”, Hertfordshire County Council (HCC) staff in collaboration with others from the District/neighbouring councils and representatives from the EA and Thames Water have formed a working group called NETSWA (North East Thames Surface Water Alliance). The group’s key goals include sharing flood risk management knowledge and expertise and maximising value for money through joint working and procurement where practical.


In addition HCC is one of 77 local authorities to receive money (£200K) from a £9.7M Defra budget allocated to fund county and unitary authorities for “early action” to implement the recommendations of the Pitt Review. The funding was awarded to authorities for the management of surface water flooding for work to commence this year (2009/10) and continuing into 2010/11. The grant from Defra is intended to primarily fund the preparation of Surface Water Management Plans (SWMPs) for tackling known surface water problems, mapping drainage assets, and introducing oversight and scrutiny of local flood risk plans and strategies specifically for the St Albans and Watford areas.”

In essence SWMPs are frameworks through which key local partners with the responsibility for surface water and drainage in an area work together to understand the causes of surface water flooding and agree the most cost effective way of managing surface water flood risk. It is therefore intended that the SWMPs for St Albans and Watford will be developed under the NETWAS umbrella to obtain the most benefit from the Defra grant.

3.3 HertsDAM System for Drainage InventoryAs noted in the TAMP’s asset summary for drainage, very little inventory data (excluding the approx number of carriageway and footway inlet gullies) is currently held for the highway drainage system in Hertfordshire, a situation similar to most other highway authorities throughout the UK. As part of developing the SWMP’s for St Albans and Watford it has been agreed to use the Design Team’s HertsDAM system for data capture and recording. It is hoped that over time the methodology used in these two districts for drainage data collection and recording can be “rolled-out” across other key parts of the HH drainage network as resources and funding allows.

The HertsDAM technology captures drainage asset details such as locations, invert levels, direction of buried pipe runs, construction materials etc and also records details of damage that has occurred to the system. The data is recorded in the site based ‘toughbook’ computer and subsequently downloaded onto the system back in the office, where it will ultimately be included in or linked to Confirm, the new asset management system.

3.4 Condition / PerformanceGullies are emptied annually on a fixed schedule, with a small proportion of “vulnerable sites” cleaned more frequently. When emptied these should be filled with water to check that they run clear and any faults are reported. With little inventory information available, the condition of most of the buried pipe network and other facilities is not known. Only those parts of the drainage network identified as having a potential problems are inspected (with CCTV) before minor repairs or a scheme is implemented.

3.5 Programme Delivery (IWP) 2008/09

IWP drainage scheme are usually delivered over a 2 year rolling programme. In year 1 selected sites are investigation to identity and understand the drainage problems more fully and generate schemes for prioritisation and construction in year 2. As well as constructing schemes identified in year 1, another round of drainage investigations is commenced in year 2.


The table below summarises the value of drainage work delivered under the IWP during 2008/09:

Drainage No Schemes Total CostsDraining Investigations & Works Delivery 75 £977,459

The drainage schemes delivered under the IWP for 2008/09 resulted in the following outcomes:

Outcome No

SchemesSites Investigated (Investigation identified that more substantial repairs would be required – via IWP schemes in second / subsequent years) 44“Quick Win” sites (Problems were solved during investigation, by surveying / cleaning the drainage system) 6Minor Works (repair of broken pipes etc) 4Major works (improvement or installation of new drainage system) identified from investigation undertaken in previous year(s) 103rd Party works (Water Authority outfall issues or damage to highway drainage system by 3rd party) 9Cancelled Schemes (Works no longer required) 2Total: 75

3.6 Programme Planned (IWP) 2009/10:

Identifying drainage schemes for IWP; The majority of drainage schemes are identified by the local area teams who collate a list of problem sites each year. These sites are then pulled together into a county wide spreadsheet for ranking and prioritising. The ranking and prioritisation process (still somewhat subjective) takes into account various factors such as: whether vehicles or pedestrians have been impeded, properties have been flooded, insurance claims, level of reactive maintenance, frequency of occurrence etc.

The table below summarises the number and value of drainage work intended for delivery under the IWP during the current year 2009/10:

Drainage No Schemes Total CostsDraining Investigations & Works Delivery 56 £1,009,383

Note: that this total does not include 20 number schemes carried over from previous years under their original IWP numbers.

Drainage schemes included in the current (2009/10) IWP are a mixture of sites identified for investigation, schemes developed from investigations undertaken in 2008/09 and or schemes carried over from previous years. These schemes comprise the following:

Proposed schemes No SchemesSites identified for investigation 26Minor Works (Repair of broken pipes etc) 8


Major works (improvement or installation of new drainage systems) identified from investigation in previous year(s) 393rd Party works (Water Authority outfall issues or damage to highway drainage system by 3rd party) 2Cancelled Schemes (Works no longer required) 1Total: 76*

Note: * Includes 20 schemes with original IWP number carried over from previous years

Schemes Identified for delivery each year can comprise of the following works:

Repair or replacement of existing drainage system due to structural failure, e.g. collapsed pipe work.

Replacing non-functioning highway drainage system, due to poor location / lack of maintenance (blocked soakaways remote from the highway)

Upgrading an existing drainage system due to capacity issues or lack of gullies

Provision of new drainage system, where no system previously existed. Rectifying outfall problems from existing drainage system into receiving

rivers/ditches. Overcoming capacity issues with Water Company surface water

sewers Repairing and recovering costs for damage to highway drainage

systems by 3rd Parties (e.g. utility company activities)

3.7 Work-Streaming / Efficiency / Innovation

3.7.1 Work-StreamingAs noted in the TAMP asset summary for drainage, historically drainage schemes (both works and investigations) were undertaken by the area offices on a site by site, case by case basis rather than being pulled together into a network wide programme such is the case for carriageway re-surfacing. More recently however local area teams (as highlighted by the work in the south west office)m have been combining drainage investigations into packages of work, with the design team ensuring that these are undertaken to a similar format as outlined in the drainage strategy / data collection standard.

3.7.2 EfficienciesFrom investigation works undertaken over recent years it is apparent that highway drainage system are susceptible to damage by third parties such as gas and water utility companies. Costs have been successfully recovered from third parties on several occasions recently and, to reduce the pressure of this damage on HCC’s maintenance budgets, a procedure is currently being developed to assist officers on how to identify third party damage and follow the correct course of action in getting the drainage system repaired and costs recovered from the third party.

3.7.3 New TechnologiesTrial sites are currently being selected to trial the following new equipment:


The “Flusher”; - is a self cleansing system for low flow drainage systems. This is being investigated for those outfalls that discharge into ditches to reduce maintenance costs and traffic management implication while maintenance works are carried out.

SewerBatt; - new equipment being developed to undertake underground drainage pipe surveys using sonar technology to detect the location of blockages and obstructions, thus reducing the need for expensive CCTV (camera) surveys. Trails are programmed for December.

3.8 Ongoing IssuesThe main issue remains the incomplete or missing inventory of the highway drainage system. Where hardcopy records exist in the area offices there is a real risk that this information could be lost.Each area office holds a record of its “vulnerable gullies” (those requiring more maintenance) but currently there is no process for pulling this information together for evaluation and review over the whole HCC drainage network.There is currently no comprehensive guidance available for HH staff that specifically covers the design and maintenance of the highway drainage system, although this should be addresses in the drainage lifecycle plan currently under development. Of particular concern is the lack of expertise in understanding the complexities behind drainage problems in the current climatic conditions and the solutions that may or may not be available to rectify problem sites.Design requirements for highway drainage systems to be adopted are included in the HCC document “Roads in Hertfordshire” (currently under review). However current requirements specify that the design of highway drainage systems should comply with 1 in 10 year storm events, whereas equivalent requirements in water company “Sewers for Adoption” requires a much higher standard of design to comply with 1 in 30 year storms events.


4 Footways and Cycle Tracks

4.1 Footway Network SurveyThe Footway and Cycletrack Management Group (FCMG), a national sub-group of the UK Roads Board, has published a draft methodology for what it is calling the Footway Network Survey (FNS).

Currently footway condition data can be collected by a Detailed Visual Inspection (DVI) but, as the name implies, this survey collects a lot of detail and is therefore very expensive. The amount of detail collected includes individual faults whereas the FNS will, instead, record an overall level of condition on a straightforward scale, which should make it cheaper to do. This is likely to be sufficient information both to rate the overall condition of the asset to measure performance and also to do a pre-selection exercise to find sites to consider for future schemes. At the moment scheme selection for footways relies mostly on the local knowledge of HH engineers, making it a subjective process and meaning that sites that have not been visited recently may be overlooked.

This survey therefore offers a number of potential improvements to the footway service in the future and we will be looking to run some trials of the survey once the detailed guidance is available.

4.2 Footway Hierarchy Review:As part of developing the footway lifecycle plan in level two of the TAMP, we are currently in the process of reviewing the current HCC footway hierarchy and its application. As part of this review we will also be considering the cycle track hierarchy; currently HCC has only one hierarchy for cycle tracks and the review will consider whether this is appropriate and, if not, what the hierarchy should look like.

The current footway hierarchy is as shown in the table below and is primarily used for the scheduling of safety inspections across the network.

Priority Name & Description Safety Inspection Interval1 High Traffic; Town and city centres and outside rows of

local community shops 1 month

2 Medium Traffic; Busy urban footways leading from housing estates to town and city centres, transport interchanges, frequently used public amenities. Main streets in villages

3 month

3 Low Traffic (High Risk); Housing estates with high incidence of defects due to age of footway, extensive utility trenches or vandalism. Lengths where there is significant high Number of vulnerable users, e.g. outside old peoples homes

3 month – NB some of these are walked also

4 Low Traffic – Urban; Housing estates and other urban footway 6 month

5 Low Traffic – Rural; Little used rural footway AnnuallyTable of Inspection Frequencies taken from “HCC Highways Works Contract – volume 1 – clause 3502R”


4.2.1 Why review the footway hierarchy?

The current footway hierarchy used in HH has been in place for some time (since the start of the current contract) and not reviewed against the 2005 Code of Practice or updated. In addition our percentage of high and medium use footways (14%) is relatively high in comparison with our neighbours, meaning that we do not necessarily focus on the genuinely busy footways.

Furthermore as part of the “Cat 1 and Cat 2 Service Value for Money Study” it was found from viewing sample GIS data that the current footway hierarchy appeared to be incorrect or inappropriate in some locations and it was recommended that a comprehensive hierarchy review should be considered.

A functional footway hierarchy is an integral component in developing the footways lifecycle plan and as well as detailing service standards for asset inspection and reactive repairs (as is currently the case). It should also be the basis for developing and documenting service standards for planned works such as asset renewals and/or upgrades.

4.2.2 The Proposed Review of Hierarchy

This should be based on its functionality and use and therefore take into consideration:

The needs of the current and future user The nature of the area (e.g. residential/industrial/rural/retail etc) Anticipated pedestrian volumes Accident and other risks assessments Character and traffic volume of adjacent carriageway

Any new cycle track hierarchy would be based on similar principles.

4.3 Performance

The footway condition indictor has improved steadily year-on-year for the last four years and improved again this year. A graph of performance is included in section 2 with the carriageway indicators.

It should, however, be noted that this performance measure only covers the busy footways – those categorised as high-use or medium-use in our hierarchy. This indicator, which used to be a national BVPI but was dropped from the most recent list, has been kept by Hertfordshire and many other authorities as a local indicator since it is the only nationally recognised measure of footway condition. It is not extended to all footways because of the cost of collecting the inspection data on which it depends. However, it is hoped that the Footway Network Survey mentioned above will offer a more cost effective way of gathering footway condition data in the future and allow us to better measure and manage all our footways.

4.4 Programme Delivery 2008/09

The table below summarises the quantity and value of footway schemes delivered under the IWP during 2008/09:


Footways Total Costs Total Length (m)Footway Micro-Asphalt / Thin Surfacing £983,712 31,294Footway Surfacing £683,934 19,838Footway Recon / Recycling £1,852,813 34,162Total £3,520,460 85,294

4.5 Programme Planned for 2009/10

The table below summarises the number and value of footway schemes intended for delivery under the IWP during the current year 2009/10:

Footways Total Costs Total Length (m)Footway Micro-Asphalt £616,733 32,980Footway Surfacing £908,445 41,293Footway Recon £562,226 5,679Total £2,087,404 79,952

4.6 Future Projections

4.6.1 Headlines Only the top 14% of footways are systematically measured and

reported PCF (preferred cash flow) should hold this close to steady state This however masks the condition of the rest of the footway network

4.6.2 No deterioration modelling is available for footways so predictions are on a more traditional lifecycle model

4.6.3 Only the high- and medium-use footways are regularly and systematically surveyed and reported for condition. The rest of the footway network receives safety inspections only.

4.6.4 The footway system prioritises higher use footways for obvious and sound reasons but this does mean that, by concentrating on these footways we can influence the condition more easily. Concentrating most intensely on 14% of the footway network which typically receives around half the funding will not address issues on the majority of the footway network.

4.6.5 It is hoped that the proposed new Footway Network Survey, when introduced, will provide a method to measure and manage the condition of other categories in the future.

4.6.6 The current PCF budget should be sufficient to continue to hold the reported footways (was BV187) at or close to a steady state although this will be, to a degree, at the expense of the low-use footways.

4.6.7 Reductions in budget below the PCF would hasten this deterioration. In the short term this might only be a worsening of 1-2% in year but, as with other assets, the full effects would be felt further down the line as the preventative treatments we didn’t do make their absence felt.


5 Intelligent Transport Systems

5.1 ITS Infrastructure

Intelligent Transport Systems (ITS) are a key tool in managing traffic to get the most use out of the existing road network. There are approximately 20 new Traffic Signal sites per year. These come from things like the adoption of

new developments, area plans and regeneration projects.

The main ITS assets accommodated at Highways House include the Urban Traffic Control (UTC) system. This system is currently being replaced to Urban Traffic Management Control (UTMC) compliance system, with a target date of October 2010. In addition HCC are currently phasing in an Automatic Vehicle Location (AVL) system.

5.2 Summary of ITS Type Assets

TYPE QuantitySignalised Junctions 178Pedestrian / cycle crossings 425Vehicle Actuated Signs 78Variable Message Signs 4CCTV Installations 5Wig-Wag systems 2Controlled Bus Access Systems 4Fire Station Priority Systems 4CCTV Monitoring System 1Tunnel Monitoring System (Baldock) 1Rising Bollards 3

Passenger Information Systems:Departure Screens (25 sites, 91 screens) 25ePIPS (Information Points) 42Total Sites 772

5.3 Programme Delivery (IWP) 2008/09:The table below summarises the value of signal schemes delivered under the IWP during 2008/09:

Signals & ITS Capital No Schemes Total CostsIntelligent Transport Systems (Design & Delivery) 9 £162,000Signal Refurbishment (Prep & Works Delivery) 18 £390,000Total £552,000

5.4 Programme Planned for 2009/10:The table below summarises the value of signal schemes intended for delivery under the IWP during the current year 2009/10:


Signals & ITS Capital No Schemes Total CostsITS Refurbishment & Delivery 18 £280,000Signal Refurbishment (Prep & Works Delivery) 37 £550,000Total £830,000

5.5 Key IssuesA typical design life for traffic signal equipment is 15 years yet 46% of the traffic signal sites are more than 15 years old. Each year there are an additional 25 sites (around 4% of the overall stock) reaching the end of their service life.

While many installations last beyond the design life, obsolescence, rather than outright failure can often be a problem with replacement parts hard to source for older installations, especially the often-complex electronics used in control systems. This may mean that a larger system needs to be replaced because of a failed component.

Other ITS Control systems are generally obsolete after 6 years and in need of replacement after 10 years. Emergency replacements typically cost 50% more than planned replacements and allowing the equipment to fail before replacement also raises issues around safety from unplanned outages.

Improved life cycle planning will help to prioritise planned replacement programmes and will also help designers consider the most effective form for new and replacement systems.

Traffic Signals and VA Sign Age Profile

24 1030 22 24 24

77

24 26 19 19 17 18 23

356

0

50

100

150

200

250

300

350

400

Age of Installation in years

Num

ber o

f Site

s

5.6 Innovations and Efficiencies

The introduction of new technologies offers scope for a number of innovations and efficiencies. Following trials, all new and replacement traffic signal sites will utilise modern Extra Low Voltage (ELV) equipment.


Because these installations use less energy, they cost less to run than older installations and are also safer because they reduce the need for higher voltage equipment installations on the highway. They also tend to require less cabling which, in turn, means less ducting. This can help to reduce the cost and disruption associated with installing the equipment.


6 Street Lighting

6.1 Street Lighting Service Review

6.1.1 Background

Hertfordshire Highways currently maintains around 110,000 street lighting columns, 14,000 illuminated signs and 11,000 other lighting units. The budget for the street lighting service in 2009/10 is £10.6m. This is broken down as follows:

£4.22m energy costs £4.72m maintenance costs £1.67m replacement and refurbishment (capital costs)

It is estimated that around 60% of lighting columns in Hertfordshire are at least 40 years old, with many of this number consisting of an obsolete concrete type which are at a higher risk of failure. (The normal design life of a street lighting column is 25 years, although it is acknowledged within the industry that modern columns will last much longer than this.

The current capital budget allows for just over 1,000 columns to be refurbished or replaced each year, meaning that full renewal of the street lighting asset would take more than 100 years. To significantly reduce the age profile of the existing street lighting stock it is envisaged that an annual replacement programme of around 5,000 columns would be needed.

The cost of the maintaining the current street lighting service is projected to rise in future years, due to a number of factors including increasing maintenance and renewal costs as the stock gets older and higher and more volatile energy costs.

6.1.2 Reducing Energy Use / Carbon Footprint

In 2007/08 the street lighting service consumed over 42 million kWh of electricity, and was therefore responsible for 22,300 tonnes of CO2 emissions, making up 17.7% of HCC’s total carbon footprint. The recently published ‘Corporate Plan 2009/12: County of Opportunity’ includes a commitment to “reduce the energy used by street lighting”, in order to cut CO2 emissions and the costs of energy.

There are a number of potential policy options for reducing the energy used by street lighting, these include:

Restricting additions to the inventory Permanent removal of street lights and sign lighting Converting 24-hour sign and bollard lighting to night-time only Part-night dimming / lighting

There are also a number of new developments that would involve the use of newer and more energy-efficient equipment such as remote monitoring, white light, or LED lighting. However most of Hertfordshire’s ageing street lighting infrastructure does not currently have the capability to deliver many of these technical options.


6.1.3 Street Lighting Review

In order to pursue the options noted above, it will therefore be necessary to review and revise the way in which the street lighting service is funded, procured and delivered. The proposals for the content and programme for the service review are based on Hertfordshire practice and will also satisfy the requirements for preparing an Expression of Interest for PFI (Private Finance Initiative) credits. The review consists of the following stages:

Identifying the Strategic Context Agreeing Policies and Objectives Scoping the Work Required Option Identification Option Appraisal Risk Assessment Stakeholder Engagement Reporting to Elected Members Preparing an Expression of Interest

6.1.4 Private Finance Initiative

It is likely that one of the more attractive options identified by the review will be to pursue a partial or fast-track replacement delivered through a PFI programme, in which responsibility and risk for the design, build, finance and operation of the street lighting service would be transferred to a private sector company or consortium.

This option is attractive because, if a bid for PFI credits is successful, the capital costs of replacing lighting columns and equipment above the ‘do minimum’ option could be met by funding from the Department for Transport. The PFI credits available for street lighting PFI programmes therefore cover a larger proportion of overall costs than in other areas such as waste management.

Due to the size, age and condition of the lighting stock, and based on awards to other councils, Hertfordshire could expect to receive at least £100m in PFI credits over 25 years, with the majority of investment taking place in the first five years - the Core Investment Programme Period.

6.1.5 Current Status of Review

The PFI expression of interest is currently being prepared and due to be submitted to the DfT on 7th December 2009.


6.2 Programme Delivery (IWP) 2008/09

The table below summarises the value of street lighting schemes delivered under the IWP during 2008/09:

Street Lighting Capital No Schemes Total CostsColumn Replacements (No Schemes / Columns) 176 / 559 £840,000Refurbishment Schemes TBA £480,000Total £1,320,000


The table below summarises the value of street lighting schemes intended for delivery under the IWP during the current year 2009/10:

Street Lighting Capital No Schemes Total CostsColumn Replacements (No Schemes / Columns) 201 / 640 £920,000Refurbishment Schemes TBA £520,000Total £1,440,000


7 Structures

7.1 Headlines / What’s New

As discussed in section 1 of this report, in October 2009 CIPFA published the “Draft Transport Infrastructure Assets Code - Guidance to Support Asset Management, Financial Management and Reporting”. The purpose of this Code is to support an asset management plan (AMP) based approach to the provision of financial information about local authority transport infrastructure assets, which includes highway structures.

The draft Code provides an overview of the approach to be undertaken in valuing transport structures, but more detailed information will be contained in the Highway Structures Asset Management Planning Toolkit, currently under development and due for release in March 2010.

It is expected that the toolkit will provide a simple spreadsheet approach for calculating the gross replacement cost (GRC) and depreciated replacement cost (DRC) of an authority’s structures stock. It is anticipated that these spreadsheet models will closely resemble the London BMS (bridge management system) model that has already been provided to authorities for review and comment. However, for the financial reporting requirements of HCC’s 2500 plus structures, a more sophisticated specialist software system may be required.

A comprehensive GRC valuation will be undertaken on the structures asset during 2010/11 once the updated guidance and toolkit is available.

7.2 Asset InventoryThe total number of structures including third party structures within the county is near to 2500, with some 720 owned by 17 different third party owners. The actual number of HCC structures could be in excess of the above number as the proprietary bridge database BMX (Bridge Management eXpert) is still being updated and in addition the current retaining wall inventory does not include many of the retaining wall structures built as part of new town development in 1960s and 70s, for instance in Stevenage.

7.3 Condition and PerformanceThe condition rating of the structures stock is determined from calculating the “CSS Bridge Condition Index” (BCI) for each structure, following a bi-annual general inspection and complemented by principal inspections of 6-10 year cycle. The BCI (ave) is the average BCI for a bridge evaluated taking into account the condition of all structural elements in a bridge. The BCI (crit) is the critical BCI for a bridge evaluated taking into account the condition of those elements deemed to be of a very high importance to the bridge.

The Bridge Condition Indicators for 2009 at 12.11.2009 are: BCI Average = 87 BCI Critical = 85

(NB scores out of 100, where a high result is a good score)


Trends in the condition of the structures stock; Stock BCI (ave) over the last 4 years is shown in the graph below.

Note: The results for years 2006 and 2007 are based on data imported from the HCC ‘BCI’ bridge condition database (pre CSS ‘BCI’) and due to the translation matrix for such conversion, is not considered to be robust when compared with the actual condition inspection data (based on the new CSS BCI without translation) used for determining the results for 2008 and 2009. Furthermore, with only one general inspection cycle complete, HH Bridge Inspectors are still in the process of improving their interpretation of the BCI criteria and thus inspections could vary over the next cycle until this process is fully embedded and a comprehensive audit of inspection results is completed.

In subsequent APRs we would aim to break down the above BCI results in more detail to improve how we report performance of the structures stock. This is likely to be down to the level of structure type and sub-type; for example bridges might be split into concrete, steel, masonry arch etc. 7.4 Programme Delivery (IWP) 2008/09

The table below summarises the value of structures work delivered under the IWP during 2008/09:

Bridges Capital No Schemes Total Costs

PRN Bridge Programme Parapet Upgrading (works) 14 £2,091,000

Capital Bridge Programme

Bridge Strengthening 2

£2,202,000

Parapet Upgrading 5Vehicle Excursion / Rail Protection Works 8

Major Maintenance - Waterproofing 1

(NB Schemes consist of a mixture of prelim, design & works)

A10 Saunders Culvert 1 £300,000 Total 4,593,000

.



The table below summarises the value of structures work intended for delivery under the IWP during the current year 2009/10:

Bridges Capital No Schemes Total Costs

PRN Bridge Programme

Strengthening (works) 3 £1,445,000Parapet Upgrading (works) 18

Capital Bridge Programme

Bridge, Edge & Guard Strengthening 17

£1,300,000

Parapet Upgrading 6Vehicle Excursion / Rail Protection Works 26

Major Maintenance 14(NB Schemes consist of a mixture of prelim, design & works)

A10 Saunders Culvert 1 £300,000 Total 3,045,000

7.6 Future Projections and Options

7.6.1 Condition Projection

Until further rounds of general inspections are completed, the data audited and the BCI figures recalculated it is impossible to derive at an accurate projection of future condition for the structures stock.

7.6.2 Demand

Growth in the asset due to adoptions from new developments has slowed down over the last two years due to the down-turn in economy. However, there are several new land mark structures such as the Baldock tunnel and associated structures and the Bishops Stortford goods yard footbridge in the process of being adopted / constructed with GRC values in excess of £1m each being added to the structures inventory.

7.6.3 Forward Works Programme

Current condition data obtained from the general inspections over the last two years is being combined with other information stored within the BMX structures database to develop a five-year forward works programme for the structures stock. The work identified mainly falls within the following categories:

Bridge parapet upgrading and or replacement Rail protection measures Bridge strengthening Structure refurbishment / reconstruction works


Bridge surfacing / waterproofing / painting Bridge joint and bearing repairs and or replacement General maintenance; brickwork / masonry repairs etc

Currently this programme is at a draft stage. More work is being done on lifecycle planning to help identify key priorities which will, in turn, define what additional information is needed to fully evaluate issues like of risk and network and asset management implications. In the addition, this programme will need to be reviewed against those existing works already identified in the parapet upgrading programme and any works originating from the review of substandard structures currently underway.

7.7 Key Issues

There are still 68 “provisional” substandard structures remaining from the assessment process undertaken in the late 1990’s, which may require additional / interim works to bring them up to standard. A project has been commissioned this year (2009/10) with the Design Team to review and report on these structures using form “BD79; Management of Sub-Standard Bridges”. However progress on the project is slow to date.

From previous surveys, 606 bridges were found to have sub-standard parapets and a programme was introduced to upgrade or replace these, with high priority sites to be targeted first. Approximately five parapets per year are being upgraded, with some 40 “high priority” sites still to be resolved. Due to the high capital cost and the consequent slow progress in resolving these sites, a review of the existing prioritisation process should be undertaken to ensure that the parapets at greatest risk are being prioritised for upgrading.

A draft 5-year forward works programme based on current condition data and backlog is being developed for the structures stock, but this is still to be fully evaluated and prioritised for delivery.

A gap analysis on the structures service has highlighted the possibility of additional work yet to be identified from new assessments, structural analysis reports and the structural reviews of bridges having passed their design life expectancy of 120 years.

Migration of data into the new BMX structures database has been completed, although validation of the data requires more time. In particular the data on structure capacity will require manual checking of the assessment data for integrity. We have also made a big effort to digitise the existing bridge data, with this process approximately 75% complete and due to finish in 2010.

Our inventory for retaining walls is incomplete and will require a major study to identify the likelihood of HCC ownership or clarify legal ownership issues.


tamp apr 2009 - hertfordshire€¦ · web viewthe actual number of hcc structures could be in...

Documents