Document Control
Revision:
| Version | Date | Author | Change Description |
| 1.0 | 27/08/20 | Document Prepared | |
| 2.0 | 07/03/2022 | K Northcott | Document Updated and Reviewed |
| 3.0 |
Introduction
Asset management is widely accepted as a means to deliver a more efficient and effective approach to the management of highway infrastructure assets through longer term planning and ensuring that levels of service are defined and achievable for available budgets. This approach supports making the case for funding and better communication with stakeholders facilitating a greater understanding of the contribution highway infrastructure assets make to economic growth and the needs of local communities.
This document outlines the approach to management and maintenance of the Footway and Cycleway asset.
Context
Lifecycle planning is key to asset management and acts as a means to link the priorities identified in the Asset Management Objectives (see Asset Management Strategy) with the works being carried out on the network. Through the analysis of asset management data this process forms a framework of identifying the required maintenance activities to meet these objectives, to select and prioritise these activities into a programme of works and to then assess the effectiveness of the process in meeting the defined objectives (see below).
Asset Management Objectives:
- To provide a safe, efficient, accessible and health-enabling highway network
- To reduce the environmental impact of the highway asset
- To deliver cost effect asset management
- To encourage the adoption of innovation in the highway service
Footway Lifecycle Plan
This document sets out the 5-year lifecycle plan for the footways managed by Plymouth City Council. This footway network comprises of approximately 900km with a gross replacement cost of nearly £182 million. The aim of this lifecycle plan is to provide decision-making support to Plymouth City Council on how to best manage their footway stock over the following 5 years.
The lifecycle plan is based on the results of extensive modelling; using sophisticated analytical techniques to determine the most cost-effective footway treatment programme across all of the footways managed by Plymouth City Council. The model was run with fixed budgets and processed using a deterioration model extrapolated from a visual condition survey.
This lifecycle plan will inform Plymouth’s decision-making regarding the management of their footways over the next 5-year period, with the following considerations:
- Cost-effectiveness: maximising the benefit of maintenance spending
- Investment planning: comparing investment profiles; forecasting budgetary requirements
- Asset Criticality
- Public safety: ensuring that trip risks are effectively managed and claims are minimised
- Acceptable condition levels: maintaining
- Performance management: monitoring performance against targets
Highways Maintenance are responsible for managing Highways Maintainable at Public Expense (HMPE). These details are maintained as a GIS layer and regularly updated to reflect any extinguishments or new adoptions.
Footway Asset Data Management
Footway Hierarchy
In line with Well-Managed Highway Infrastructure Code of Practice, Plymouth are using a network hierarchy that is defined by considering current and expected use, resilience, and local and social factors such as hospitals, schools and industry. The table below describes the definition of each hierarchy.
| Category | Hierarchy Description | Type of Footway Description |
|---|---|---|
| 1a | Prestige Walking Zones | Very busy within the City with high public space and street scene contribution and tourist destinations. |
| 1 | Primary Walking Routes | Busy urban shopping and business areas and main pedestrian routes linking interchanges between different transport modes. |
| 2 | Secondary Walking Routes | Medium usage routes through local areas feeding into primary routes, local shopping centres, large schools and industrial/commercial centres. |
| 3 | Link Footways | Linking local access footways through urban areas and the main routes and cul-de-sacs |
| 4 | Local Access Footways | Footways associated with low usage, short estate roads to the main routes and cul-de-sacs. |
Condition Survey
The footway condition data is collected through a high definition camera survey. This information provides the basis for the identification of treatments and the associated performance measures. The data collected from the survey are used to model lifecycle analysis. Defects collected through safety inspections can also highlight condition and can be used when developing programmes. Plymouth are keen to utilise this data set in the future.
Inventory Data
Accurate and up to date inventory of the asset is an important element to good asset management. The high definition camera survey collects inventory such as surface type which are incorporated into the footway modelling process.
Data Management
The management of data for the highway authority is outlined in the data management strategy. The footway asset data is held in the strategic asset management system which holds the indicated programmes of works based on the current condition of the network and the prediction of future condition of the network based on how the network has previously deteriorated.
In this lifecycle plan, only the performance indicators calculated through the condition surveys are considered however any planned maintenance activities will also have a positive impact on the number of reactive repairs required and claims made against the city.
Performance Management
Plymouth monitor the progression of condition across the network on 3- yearly basis. Targets against these performance measures are reviewed regularly to consider changes to best practice, legislation, the corporate objectives and to consider any changes to funding levels.
There are also a number of performance monitors that are identified within the Performance Management Framework (PMF) to support the implementation of the Asset Management Strategy. These have targets which are assigned and reviewed annually. The below table sets out these measures and the results identified for financial year 2020-2021.
| Performance Monitor | Definition | 2020/2021 Target | 2020/21 Result | Reporting Frequency |
|---|---|---|---|---|
| AI-FW-001 | % of footways network treated | 0.34% | 0.38% | Annually |
| CE-FW-001 | % of footways requiring maintenance | Not a measurement year | Not a measurement year | 3-yearly |
| CE-FW-002 | Number of Jobs in the Workbank for Footway | <150 | 74 | Quarterly |
| CE-FW-003 | Number of Jobs in the Workbank for Kerbs | <100 | 21 | Quarterly |
| SE-FW-001 | % of footway defects completed on time | >=97% | 96.5% | Quarterly |
| SE-FW-002 | % of Kerb defects completed on time | >=97% | 90.6% | Quarterly |
| SE-FW-003 | % of footway claims repudiated | 53% | 78.2% | Quarterly |
| SE-FW-004 | % of footway safety inspections completed on-time | 97% | 99.67% | Quarterly |
| SE-OA-008 | "Pavements & Footpaths (Overall)" satisfaction score from NHT survey (KBI11) | 58% | 51% | Annually |
Reactive Maintenance and Defect Repairs
Routine footway maintenance focusses predominantly on safety defects found on the network through inspections and those reported by members of the public. The Highway Safety Inspections Manual which has been updated in line with the Code of Practice identifies:
- Frequency for routine inspections per footway hierarchy
- Intervention levels
- Time scales for defect repairs
Safety defects are recorded by highway inspectors during the routine inspection of the network. These defects are then classified for repair following the risk based approach as defined in the Highway Safety Inspection Manual. These repairs are recorded electronically on the maintenance system, which enables the quality assurance of repairs and supports this with evidence fed back from the contractor undertaking the work. These repairs will also be co-ordinated with the structural repair programme to ensure that where efficiencies can be made, they are.
Structural Maintenance Strategy and Investment
A programme of planned maintenance on the highway network is carried out annually, with the schemes including footway and cycleway reconstruction, surfacing and slurry sealing.
The principles of asset management are being applied to the City Council’s footway and cycleway network in order to ensure there is timely intervention to make best use of the resources available.
The need for major works is identified by assessments considering condition, footway classification and network importance. The intention is that the application of asset management principles should continue to be applied to the footways asset to maintain it (as a minimum) at steady state levels.
Lifecycle Analysis Model
The Lifecycle analysis modelling process involves a number of steps as described below. This defines the parameters that describe the behaviour of the model. These include the following, some of which are described in more detail later:
- Treatments
- Maintenance Plan
- Analysis Criteria
- Prioritisation
- Budget constraints
Treatments
Plymouth have developed a range of different treatments that are in use in various combinations on different parts of the network to provide the required levels of performance.
Treatment types are considered and applied based on footway hierarchy. Surface type can also be used to apply treatments however Plymouth is focused on using footway hierarchy to ensure the highest priority footways are maintained as required.
For the analysis, we have used “Generic Treatments” where various specific treatments are grouped together into the following generic Treatment categories:
| Hierarchy Class | Operation |
|---|---|
| 2, 3a, 3b, 4a, 4b | Bituminous resurfacing |
| 2, 3a, 3b, 4a, 4b | Concrete to Bituminous Surface |
| 2, 3a, 3b, 4a, 4b | Natural Stone To Natural Stone Resurfacing |
| 2, 3a, 3b, 4a, 4b | Concrete Resurfacing |
| 4a, 4b | Slurry Seal |
| 4a, 4b | Concrete Flags to Bituminous Surface |
Work Package Areas- Through an analysis of potential deterioration scenarios, a series of work package areas (WPA’s) have been identified. These work package areas are sites or groups of sites where the need for a potential scheme is identified in the analysis period.
Treatment life & Unit Cost - Our approach to modelling is to base the key inputs on experience and good engineering judgement. Treatment life has been chosen to match industry-expected norms. Each treatment has a unit cost which is used to calculate the cost of the works. For example, resurfacing will have longer life than slurry seal, but will also be significantly more expensive.
Maintenance Plan - From the analysis undertaken in the asset management system, a maintenance lifecycle plan is created which identifies the expected planned maintenance needed on the network. This plan is important in that it ensures that future maintenance work is properly scheduled and this in turn has the effect of preserving the network.
Analysis Criteria
Lifecycle analysis to generate set of treatment schedules are carried out using the High Definition Camera Survey data.
The footway survey records an overall condition grading from 1 to 5 which is used to identify footways in need of maintenance. Although the survey does identify defects such as cracking, vegetation, the severity of the defects is unknown.
Prioritisation
The analysis model prioritises schemes based on a set prioritisation criterion to invest the set budget allowance per year and generates scenarios to show the effect of maintenance program on the network for the analysis period. Following the risk-based approach according to the Code of Practice, we have prioritised the schemes based on the highest hierarchy of footway and sections of resilient network, ensuring the footways with the highest footfall are maintained. The benefit and potential value of schemes is also taken into account.
Budget Constraints
The schemes are generated based on all the defined criteria as mentioned above. The Work Program is based on the Budget allowed per year. Budget is the financial constraint that defines how much work can be undertaken per year.
Work Programme
The program of works is developed for a 5-year period using Asset management Software. Footway schemes generated by the automatic processes are taken as a basis for the preparation of work programs. Each “scheme” that qualifies for treatment according to the treatment selection rules is assigned a treatment type and associated maintenance lifecycle plan, and is then assigned, in priority order, to the works program. The works program is the output of the treatment parameters and rules described above, and describes in detail the work to be done, the year of implementation and the cost of each scheme.
Once the system has identified the schemes for each year, the highway engineers visit each site to validate the treatment extent and treatment options. These schemes then build up the works programs for each year which is communicated to members and the public.
Addendum – 2021/2022 and 2022/2023 Fast Fibre (LFFN) impact
A major contractor has been upgrading the high speed Fibre to the Home infrastructure since the start of the financial year 2021/2022. Due to the uncertainty around their programs and not knowing which areas they will be in and when, there was a risk of new footway schemes being excavated after our works. As a result the decision was taken to vastly reduce our Footway schemes for the above 2 financial years at least. It was agreed that as the Footway network deteriorates at a relatively slow pace this was preferable to new works being excavated again shortly after completion. The budgets saved have been utilised to carry out additional pre-patching and micro asphalting works to the carriageway over these two years.