Integrated Public Transport Strategy - Worcestershire County Council

Chapter 17 – Highway Maintenance
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On all but the most lightly trafficked roads the normal life expectancy of surfacing is 12 to
15 years and for surface dressing 6 to 8 years. It has been, therefore, a cause for concern
that frequencies for structural maintenance have extended well beyond these periods. The
1998/99 maintenance outurns provided as part of the 1999 NRMCS, indicate a
resurfacing frequency on Rural Principal roads of once every 89 years (see Table 17.2).
However, recent improvements in levels of TSG allocation, in conjunction with the
Council’s decision to increase funds available for Non-Principal road maintenance, will
see these frequencies improve.
In 1999 SCRIM surveys were carried out on 52% of the Principal Road Network. The
survey uses a machine which provides a continuous record of resistance to skidding on
wet roads. Specialist software used for the analysis of SCRIM data allows the reporting of
sections of road that fall below the required standard.
The Local Authority Code of Good Practice for Highway Maintenance recommends
standards for skidding resistance on carriageways which are dependent on ‘the degree of
difficulty’ or ‘risk rating’ of a site. The risk rating of a site is influenced by road geometry
and the presence of physical features such as junction, roundabout or traffic light
approaches.
Investigation is triggered when a SCRIM co-efficient falls below the standard specified for
the defined site risk. Previous investigations have identified that a large proportion of the
Principal Road Network falls below the standard set out in the Code of Good Practice.
Due to recent levels of funding, it has proved impossible to achieve these standards.
Therefore, in 1996, in order to achieve a better correlation with funds available, standards
were lowered by approximately 10 - 15% dependent on the site risk definition. The current
standard is set out in the 2000 Highway Management Plan of Worcestershire County
Council, a copy of which has been supplied to the Department of Environment, Transport
and the Regions.
Evaluation of the 1999 SCRIM data has shown 17.2% of the roads surveyed to be at or
below the recommended minimum levels set out in the Code of Good Practice. By
applying the revised standards adopted by the County Council, this figure falls to 7.3%.
However, out of the 7.3% of road length which falls below the County standard, current
Principal Road Maintenance funding will result in a limited number of these sites receiving
treatment, with the remainder relying on being signed.
With the implementation of the EXOR UKPMS Tranche 2 system and the resultant ability
to identify and prioritise maintenance through analysis of stored CVI data, the Council will
no longer rely on CHART survey information which has been used to support both last
years Provisional LTP and previous TPP submissions.
Table 17.3 shows the Structural Maintenance carried out on the Principal Road Network
in 1999/2000 and the proposed programme of works for 2000/2001. The 2000/2001
programme is based entirely on results of UKPMS.