Maintaining common ground
Tynemarch's Dr Jeremy Lumbers and George Heywood summarise UKWIR's common framework for capital maintenance planning
Tynemarch was commissioned by the UK Water Industry Research (UKWIR) to develop
an improved common framework for capital maintenance planning (CMP) by the UK
water industry. The final report was presented in May.
The common framework is based on the analysis of risk (specifically the probability
and consequences of asset failure) and encompasses an economic approach which
allows the trade-off between capital and operational cost options to be considered.
This enables an economic level of capital maintenance (CM) to be identified
with due regard to the costs associated with asset failure and (where appropriate)
the value placed by customers on service improvements.
The following concepts form the basis of the framework:
- capital maintenance should normally be justified on the basis of current
and forecast probability and consequence of asset failure,
- ‘consequences’ are expressed as direct or indirect impact on service and
- ‘service’ is defined as service to customers and the environment (including
all relevant third parties and regulatory requirements),
- service is assessed using suitable indicators, building on the approach
applied by Ofwat at the 1999 Periodic Review
- there is a need to demonstrate a least-cost approach to Opex versus Capex
and proactive versus reactive maintenance,
- an integrated system approach is required to assess direct and indirect
impacts on customers and the environment.
The common framework can be viewed as having eight principal components which
are covered below. The common framework moves away from previous general water
service providers (WSP) practices based on a simple conversion of condition
and performance grades into remaining asset lives.
There are two possible objectives that can be applied generally or vary with
1) to provide steady or improving service to customers and the environment
at minimum cost to the WSP.
2) to provide the level of service to customers and the environment which represents
an economic balance between the value of the service provided and the associated
costs to the WSP.
Serviceability indicators remain a central element of the common framework.
The current serviceability indicators are of two types:
Service indicators which measure directly or indirectly the service being
provided to customers and the environment – the set of service indicators
should ideally cover all areas of service, understood in this context to encompass
all regulatory requirements and to include service to customers, the environment,
third parties in the community and health and safety obligations to the public
and company employees. The development of improved indicators must be seen as
an ongoing task extending beyond the current review cycle and are the subject
of a current Ofwat consultation with the industry.
Asset performance indicators which reflect performance of an asset or group
of assets in fulfiling its intended function –
it is proposed WSPs are not required to maintain a stable or improving trend
in asset performance indicators, provided that any deterioration can be shown
to be consistent with the economic provision of service in the long term.
Proposed modifications and additions to the current set of serviceability indicators
have been provided for consultation and are included in the final report.
It is recognised no set of indicators can fully reflect all aspects of water
services, and that WSPs may at times need to present a case for CM expenditure
based on their own indicators or on broader arguments regarding the avoidance
of a future deterioration in service to customers and the environment, including
compliance with regulatory requirements. It is recommended that such approaches
are discussed with the Regulator at an early stage.
Forecasting of service to customers and environment
The common framework extends the approach used at PR99 in that the assessment
of historical service is to be complemented by the forecasting of future service,
taking account of the impact of proposed CM and operational changes.
It is generally accepted that inadequate CM will eventually lead to some form
of asset failure. Within the common framework, CM is to be justified on the
basis of the expected future impact of such failures on service and on WSP costs,
i.e. the current and future probability and consequences of asset failure.
The probability and consequences of the failure of a given asset will depend
on various attributes of the asset, termed here the ‘asset observations’. These
observations may include anything that is known or can be measured, judged or
estimated regarding the asset and its operation, environment and performance,
and which is useful for estimating the probability and/or consequences of failure.
Whilst many of their component observations will continue to be important,
the current grading systems for condition and performance assessment are not
considered to provide a suitable long term basis for asset observations within
the common framework.
The framework does not prescribe specific asset observations since WSPs have
differing views and experiences regarding the relationship between various asset
observations and the probability and consequences of failure.
Identifying the intervention options
Having estimated future service, it is necessary to identify a range of intervention
options to be considered for use in meeting the chosen planning objective. These
should include both CM schemes and operational changes, with appropriate phasing
and timing variations.
Costs and value
All intervention options considered should be costed taking full account of
capital costs, changes in operational cost and any expected savings in the costs
which result from asset failure (eg. clean-up costs, compensation payments and
the additional costs of reactive maintenance).
Where the cost-benefit planning objective is being applied, there is a further
requirement to take account of the value of any resulting improvement in service
to customers and the environment, which will usually be quantified on the basis
of customer surveys. To allow comparison of capital and operational interventions,
all costs and benefits are to be evaluated as present values using an appropriate
discount rate and planning horizon.
Selection of optimal interventions
The interventions which are required to meet the chosen planning objective are
identified using an appropriate decision-support algorithm, based on an assessment
of the comparative costs and benefits of each option.
Interventions may be included within the optimal selection on the basis of
the expected cost savings which would result in the absence of any service benefits.
Where the least cost interventions involve increases in operating costs, these
will need to be taken into account in Ofwat comparative efficiency assessments.
The common framework Process
The overall process envisaged by the framework is illustrated in figure 1. This
should not be viewed as prescriptive and WSPs are encouraged to work at an appropriate
level of detail and make adaptations where required to reflect their individual
circumstances, whilst adhering to the broad principles of the framework
The common framework is intended to provide sufficient flexibility to allow
considerable variation in the analysis undertaken, according to the importance
of the asset area, the size of the WSP and the availability of suitable data.
It was recognised that the framework should neither limit the opportunities
for companies to gain competitive advantage through innovative methods nor fetter
the regulator in his price determination.
Three water and sewerage companies and one water only company undertook a pilot
trial of the framework each focussing on different asset types. Included in
the project was the assessment of the trials using a reporter in the same manner
as is undertaken on behalf of Ofwat for a Periodic Review. The feedback from
the companies was positive as indicated by the following: “The common framework
for CMP provides a logical and well-structured methodology … which complies
with the needs of MD161.”
“[The company] was able to fulfil all of the steps and produce an asset
plan for the asset set studied.”
“[The company] believed that the framework in essence is what all good
companies should be undertaking…”
“The general principles of the model are aligned with the asset management
approach that is being implemented within the company.”
The presentation to the industry and regulators was well received and companies
are looking to develop plans for working within the framework for AMP4. The
framework should help the industry move to a more soundly-based identification
of the need for capital maintenance for both PR04 and the longer-term, within
a process agreed with Ofwat.
The forward-looking risk-based aspect of the framework will encourage consideration
of the optimal balance between proactive and reactive maintenance as well as
Opex and/or Capex solutions, and assist in achieving agreement regarding the
economic level of capital maintenance