Highways Agency

A556 Area Study

EXECUTIVE SUMMARY

This report presents the findings of a study commissioned by the Highways Agency to confirm or otherwise the recommendation of MIDMAN that A556(M) should not proceed but that a full movement interchange at Junction 20 of the M6, ie its junction with M56, should be constructed. The MIDMAN recommendation also recognised that such a strategy would probably require the widening of M6 to D4M between Junctions 19 - 20 and possibly require the widening of M56 to D4M between Junctions 9 - 7.

The study has compared the two road based options in accordance with GOMMMS leading to the production of Appraisal Summary Tables.

The study has used the MIDMAN traffic model refined to include additional minor roads, modelling of junction capacities, reclassification of existing link types, and refinement of zone loading points. Models were developed for the AM peak and inter-peak periods leading to estimated AADT flows. Future year matrices were developed for 2011 and 2026 using MIDMAN forecasts based on their Scenario 2 recommendations. Incremental assessments were undertaken with the base assessment for comparing the two options including M6 widening between J16-19 and M56 widening between J7-6 (see below). Also various options for creating restrictions on A556 with the J20 scheme were modelled; the option of closing the south-facing slips at J19 and reducing A556 to a single carriageway with a 40mph speed limit was the option taken through the remainder of the GOMMMS assessment.

The A556(M) option has been designed as a D2M, whilst the J20 scheme has included the widening to D4M of the M6 between J19-20 and the M56 between J9-7. With regard to the J20 scheme and associated widening of the adjoining motorways, two forms of motorway widening, parallel and asymmetrical, have been assessed leading to a recommendation as to which is preferable in this case.

Both options have been costed using quantities based on 1/2500 scale plans using rates published by Spons. Both options include works on the existing A556 to reduce its scale. The estimates produced were used in the economic assessment of the options.

The study used the latest available environmental data, and in the case of landscape assessment enhanced by site surveys by qualified landscape architects. Similarly, with regard to integration, the assessment of the options was against the latest planning policies. Full consultation has been undertaken with Statutory Consultees (English Nature, English Heritage, Countryside Agency and Environment Agency).

The study has also assessed the impact of the two options on the wider area network, particularly with regard to the SEMMMS strategy.

The study has concluded that the A556(M) is preferred on:

1. Traffic grounds since it caters for all motorway to motorway traffic; the J20 scheme only caters for 35% of this traffic even when restrictions are applied to the existing A556 and access thereto is limited;
2. cost grounds being some 15% cheaper than the cheapest J20 scheme;
3. environmental grounds where it is assessed preferable on 5 of the 9 subobjectives;
4. safety grounds with a saving in accident numbers over a 30 year period 6 times greater than the J20 option;
5. economic grounds with a robustly positive BCR, compared to a negative BCR for the J20 scheme;
6. accessibility grounds although this is only a marginal preference;
7. integration grounds since the scheme is safeguarded in the Development Plan, other impacts on policies being equal between the two options.
8. deliverability grounds since Line and Side Road Orders have already been made for A556(M); works could thus commence on site in 2005. However the J20 scheme would require further Public Consultation, a Preferred Route Announcement, and detailed design leading to an additional period of 4 years before the scheme could be implemented.

The study also considered in accordance with GOMMMS the need for widening the M56 between junctions 7 - 6, since this section of motorway had been considered in neither the MIDMAN study nor the SEMMMS study.

The recommendations of the study are that:

1. the A556(M) scheme be reinstated into the Roads Programme without delay at a D2M standard, with associated traffic calming on the existing A556,
2. the M56 Junctions 7 - 6 be widened to D4M standard, using parallel widening to its north side, this scheme to proceed no later than the A556(M) scheme.

---

• Proposed Route Map (940KB PDF)