Dark Lane near the bypass route at Bredbury.

In 2003-4 Stockport Council prepared its case for a “new relief road” from the M60 to M56, later split into the A6-Manchester Airport Relief Road and the proposed Hazel Grove-M60 bypass. The “appraisal” that SMBC presented to the Government in 2004 and a separate environmental assessment have helped us understand the Hazel Grove-M60 route which, ten years later, is back on the agenda. The traffic modelling figures contained in the “appraisal” are less useful.

The 2004 modelling sheds little light on the difference between having the Airport Relief Road as a standalone development (unwanted by many in Cheshire but now being built) and adding the north-south Hazel Grove-M60 bypass, as advocated by Stockport Council, Lord Stunell and William Wragg MP. Forecasts made in 2004 for Year One of a new M56-to-M60 road show traffic reductions on roads feeding the M60 at Bredbury/Brinnington ranging from 20% on Compstall Road to 33% on the A627 at Hatherlow. From these figures we can subtract three per cent for A6-MARR’s contribution  to the reductions, as indicated by modelling done later for the Airport Road. It is much more difficult to disentangle the contributions of the Hazel Grove-M60 Bypass and the Airport Road to forecasts for the A6 or the A626 at Offerton, for example.

All such figures should be taken with a large pinch of salt because of factors outlined in the SACTRA Report (consistent underestimating of traffic growth caused by new roads) and SMBC’s report “SEMMMS new relief road scheme – results and conclusions of initial assessment” (including the risk of traffic rat-running between the motorways and of junction bottlenecks). We also know that there can be large increases in traffic leading to new roads, which is demonstrated in modelling of the effects of the Airport Relief Road on the A6 south of Hazel Grove.  

The 2003-4 traffic modelling is, in any case, badly out of date and seriously flawed. At the time, Stockport Council was relying on draconian forecasts of traffic increases that never came about on local roads, excluding motorways (see Keith Buchan in NWTAR’s A Folly In The Making, available online). The Government itself criticised SMBC’s modelling for, among other things, not including “induced traffic” – users of the new road who would not have previously made the journey.

In 2011 Stockport Council revisited the traffic modelling in support of the construction of the Airport Relief Road, but ignored completely the Hazel Grove-M60 bypass which it was intended eventually to connect with. However, we have referred to the modelling for the Airport Road to obtain an (inadequate) assessment of the resilience of its junctions and to see some relevant local traffic patterns.

Stockport Council rarely helps with our requests for information (FOIs) but did provide a cost estimate at 2003 prices for the Hazel Grove-M60 bypass, which updates to produce the figure of £580 million (a simple calculation since it costs twice as much as the Airport Road). The Pathetic Motorways site has been useful regarding the unfortunate history of Stockport bypasses. Information from the campaign groups Poynton Against Unnecessary Link Roads to the Airport and Stockport Friends of the Earth (no longer running) is greatly appreciated.

To sum up, the main sources for this website are:

• Official environmental summary 2003: http://www.semmms.info/140683/semmsreliefroadenvironmentalassessmentexesummary
• Full environmental report: SEMMMS Major Road Schemes Stage 2 Environmental Assessment (available from Stockport MBC)
• Poisebrook Valley Local Nature Reserve http://www.stockport.gov.uk/services/leisureculture/parksandrecreation/parkscountry/parks/poisebrook/
• Dodge City connection http://www.stockport.gov.uk/services/communitypeopleliving/aboutstockport/twintowns/otherinternationalconnections/dodgecityusa/dodfecitylink
• The route, including both M60 to A6 and A6 to M56: South East Manchester Multi Modal Strategy, Annex E, Appraisal of SEMMMS New Relief Road July 2004 (available from Stockport MBC)
• A6 to Manchester Airport Relief Road Transport Assessment Main Text October 2013 http://a6marr.stockport.gov.uk/746597/760095/760276
• Stockport MBC’s strategy: “SEMMMS new relief road scheme – results and conclusions of initial assessment” October 31, 2003 (can be found by search engines)
• Unintended consequences of road building were revealed in the SACTRA report 1994 – Trunk Roads and the Generation of Traffic (now withdrawn from the Government’s website).
• Deaths from pollution http://www.theguardian.com/environment/2015/apr/02/air-pollution-may-cause-more-uk-deaths-than-previously-thought-say-scientists
• Pathetic Motorways http://pathetic.org.uk/unbuilt/a6m/maps/