Case study

Project Name: Avon and Somerset Tactical Information Scheme (ASTIS)
Client: HA
Location: M4 / M5 / M32 near Bristol
Duration: Sept 05 to May 07

Working as supply chain partners with Carillion we undertook traffic management at 10 different locations, each one was a major motorway traffic management scheme. A number of elements were key: -

• Working with contractor and other supply chain members to develop the programme.

• Rapid development of accurate target prices and identifying the risks for each element which was undertaken iteratively as programmes and methods changed.

Added value to the project by: -

• Providing detailed designs at earliest possible stages to communicate and consult with all stakeholders. This enabled each traffic management phase to be approved, and temporary traffic orders to be implemented promptly, allowing construction works to progress without hindrance.

• Redesigning the traffic management layout proposed by the Client’s Agent at the M4 jct 18. This reduced the traffic management costs by approximately 12% and allowed the target price to fall within budget. This was achieved by altering the line marking arrangement within the narrow lanes scheme. In addition safety was enhanced since we were able to shorten the section of narrow lanes by 1.8 km allowing traffic to travel in full width running lanes over that length.

• Redesigning the traffic management at the M32 / M4 interchange to improve working space available during each phase. Extremely high levels of traffic flow meant that out-of-hours working was deemed necessary. The Client’s Agent proposed that only lane closures be installed at night with construction work limited to these the same hours. We were able to improve the traffic management arrangement by introducing a narrow lanes scheme at the interchange, maintaining the capacity of the road and ensuring that the temporary road geometry was safe; therefore we effectively allowed Carillion access to the working areas for 24 hours per day. This benefited the Client by avoiding extended periods of night-working with the associated high costs and poor productivity. The small increase in temporary line marking charges of approximately 10% was off-set by large gains elsewhere.

• Introducing the requirements of the new version of Ch.8 of the Traffic Signs Manual, some 6 months prior to the introduction of the new manual to maximise safety for the project.

• Providing target prices with highly detailed cost build up, allowing different scenarios to be modelled and their costs calculated; During this contract we worked with Carillion on a open-book basis.

• Offering Carillion a cost saving of 5% on our charges based on the lower risks associated from working in partnership and the benefits of continuity of work.