Highways Agency - Safe roads, Reliable journeys, Informed travellers

Related pages

• Summary
• 1 introduction
• 2 traffic, congestion and safety issues
• 3 geotechnical issues
• 4 environmental constraints
• 5 option development
• 6 options considered further
• 7 engineering comparison of options
• 8 economic comparison of options
• 9 environmental appraisal of options
• 10 waste management
• 11 public open day
• 12 responses from statutory and non-statutory consultees
• 13 conclusions
• 14 recommendations
• Environmental study findings
• Environmental study findings
• Environmental study findings
• Environmental study findings
• Environmental study findings

A417 Cowley to Brockworth Bypass Improvement

5 OPTION DEVELOPMENT

5.1 Prior to assessment a process of option development was undertaken. This comprised:

• Initial reviews;
• Initial discussions with environmental statutory consultees;
• Initial option development;
• Optimising meeting;
• Option refinement;
• Second meeting with environmental statutory consultees;
• Option confirmation.

Initial Reviews

5.2 The option development process began with two reviews. These were;

• a review of environmental and physical constraints; and
• a review of options considered previously.

Environmental and Physical Constraints

5.3 A review of the information provided in Chapter 4 was undertaken to identify areas/sites that should be considered invaluable areas, which should be avoided wherever possible. The criteria used are given in Table 5-1. In addition to these environmental issues, the schemes would need to meet engineering and economic criteria.

5.4 In particular, the schemes should be:

• buildable;
• deliverable;
• improve safety; and
• economically viable.

Table 5-1 Criteria used in Option Development

1. Sites ring fenced and considered inalienable
SSSI's The Scrubs Nature Reserve Scheduled Monuments Conservation Zones Listed Buildings Crickley Hill Country Park The Star Centre Ancient Woodland
2. Areas to be avoided wherever possible
Areas of archaeological potential Trees and woods covered by TPO's Local nature reserves/SNCI Local properties - options which avoid or where possible, reduce existing impact preferred Minimum impact on broad aquifers and surface waters (springs and rivers) Minimum noise and local air quality issues Minimum waste produced, or which generate opportunities for re-use or waste. Avoid cutting local rights of way Ensure access to local properties
3. Opportunities
Options which allow improved crossing on public rights of way Options which decrease green house gas emissions from vehicles using the scheme

Review of Previous Options

5.5 A review of earlier studies undertaken for the Highways Agency in the study area was undertaken to assess if the initial assessments of these schemes could be revised due to:

• New or additional environmental or geotechnical information that had become available recently; and/or
• advances in engineering and geotechnical engineering, which would alter the technical or economic viability of options previously considered but dismissed on these grounds.

5.6 Following the reviews a "long list" of initial potential options was developed. These are shown in Table 5-2.

Table 5-2 List of Options Initially Identified

Options Identified
On-line options within highway boundary Mainly on-line options with widening/offline sections Off-line options to the east of the current route alignment Off-line options to the west of the current vents alignment "short" tunnel option "long" tunnel option "very long" tunnel option "toolkit" options "do nothing" option

Initial Discussions with Environmental Statutory Consultees

5.7 Early in the study process a meeting was held with environmental statutory consultees. Those attending are listed in Table 5-3. A separate meeting was held with English Heritage. English Nature and the Environmental Agency were invited to the meeting but were unable to send representatives.

5.8 The meetings comprised a review of the environmental constraint procedure for the study and outline discussions on options for development. The following was agreed:

• There is a demonstrated need to improve the current route and a "do nothing" scenario is not a viable option;
• The importance of the AONB and the need to consider some work within it if an improvement scheme is to be progressed. Work should be sensitive to the landscape and its historic context. The escarpment slopes of the Cotswolds plateau were noted as being of particular importance. Options taken forward should not include deep cuttings or viaducts through the escarpment slope or include a new route to the vale from the plateau top;
• The Air Balloon roundabout is a particular constraint, particularly with the designated sites surrounding it (including Crickley Hill, Barrow Wake and Emma's Grove);
• The existing situation is having a significant adverse effect on economic development in the region;
• The existing situation is having a significant adverse effect on the local community in terms of air pollution, noise pollution, safety, visual impact and accessibility.

Table 5-3 Attendees at Initial Statutory Consultee Meeting

Attendees
Countryside Agency National Trust Tewkesbury Borough Council Gloucestershire County Council Cotswold National Trail Cotswold District Council

Initial Option Development

5.9 Following the initial meeting with the statutory consultees the list of initial options was reconsidered and screened. Several options were ultimately discarded including:

• The "do nothing" option - All consultees had agreed that there was a demonstrated need for an improvement scheme and that doing nothing was not an option; and
• Options to the west of the current route - A review of issues raised in the initial statutory consultees meeting and shown on the constraints plan showed that it was not possible to define a route which did not require cuttings and/or viaducts through the escarpment slope, would not significantly impact on listed buildings, conservation zones, SSSI's, Scheduled Monuments or adversely impact the settlements of Brimpsfield and Birdlip.
• Options to the east of the current route - These would require substantial new road build through open and relatively flat landscape. These would be highly visible and impact adversely on the AONB. Large areas of archaeological potential would also be affected.

5.10 Further work was undertaken on the remaining options and indicative corridor plans were prepared for consideration at the subsequent "optioneering" meeting.

Optioneering Meeting

5.11 An "optioneering" meeting was held at the Highways Agency's offices in December 2001. This considered the indicative options identified in light of the environmental and physical constraints. The meeting was attended by personnel from the Highways Agency, WSP, Gloucester Archaeology and Cooper Partnership.

5.12 The meeting confirmed the rationale used in discarding the "do nothing" option and options to the east and west of the existing route. Three further options were also discarded at this meeting. These were:

• The "short" tunnel option - This proposal included portals close to Birdlip village and Crickleigh Farm. It was considered that whilst this provided few additional benefits over the "long" tunnel the gradient would be significantly steeper. It was therefore dismissed in favour of the "long" tunnel option with a shallower gradient.
• Offline options to the west of the current route - It was considered that all possible offline options to the west would have considerable engineering constraints and would be too damaging to the environment. There was no obvious route alignment that could be utilised and gradients would be quite steep. From a landscape perspective, options to the west would be likely to have substantial adverse impacts and would be visible from key viewpoints;
• Off-line options to the east of the current route - It was considered that all possible off line options to the east would be too damaging to the environment. One particular concern was the Air Balloon roundabout where environmental constraints would hinder eastern options. In addition, a new section of off-line road would have to be constructed in the AONB and it would not be compensated by removal of the existing roads. An exception to this was an off-line section of road at Nettleton Bottom. An on-line option at Nettleton would not be buildable without significant loss of properties and disruption. A short bypass, utilising the closed Birdlip Quarry, was therefore suggested to be taken and
• "Toolkit" option. This comprised a series of small scale improvements at each of the junctions whilst the road between was left largely unchanged. Traffic assessments suggest that this would not be a viable way forward.

5.13 Three options were taken forward for further consideration and assessment:-

• Option 1 - Short off-line bypass at Nettleton Bottom, on-line asymmetric widening of the current Birdlip bypass, new grade separated junction at Birdlip, redevelopment of the roundabout at Air Balloon with the addition of traffic signals, and re-modelling of lanes on Crickley Hill to keep two lanes up and provide an additional lane down, mainly within the existing highway boundary. Accesses to properties on Crickley Hill would be remodelled.
• Option 2 - Short off-line bypass of Nettleton Bottom, on-line asymmetric widening of Birdlip Bypass, new grade separated junction at Birdlip, new grade separated junction at Air Balloon, and construction of additional two lanes down Crickley Hill keeping the current three lanes up. These would be provided adjacent to the existing carriageway but at a lower level. Accesses to properties on Crickley Hill would be remodelled.
• Option 3 - Tunnel Option. A short off-line bypass at Nettleton Bottom to the southern (Cowley) tunnel portal, a 2.8 km long 14m diameter twin bore, dual carriageway tunnel which emerges at a western (Brockworth) portal close to the existing A417 near Crickleigh Farm, and link roads to the existing route. The tunnel would require two control buildings one to each portal together with link roads to the existing A417 which would be retained. A small (500 m3) reservoir (and possibly a pump house) would also be required near the Cowley (southern) portal for fire fighting purposes. The existing A417 would be retained to provide connections with the A436 and Birdlip.

5.14 Each option is discussed in more detail in Chapter 6. Plans showing the three schemes are given in Figures 5.1 to 5.3.

Second Meetings with Statutory Consultees

5.15 Two further meetings were held with Statutory Consultees on the 28th January 2002 in Bristol. The attendees at each meeting are given in Table 5-4. The meetings were intended to discuss the options to be taken forward to the assessment stage and to gather initial feedback from attendees.

Table 5-4 Attendees at the Second Consultation Meeting

Session 1	Session 2
English Heritage Countryside Agency English Nature Environment Agency Cheltenham Borough Council	Gloucester County Council Cotswold District Council Cheltenham Borough Council National Trust

5.16 The results of these meetings with environmental statutory consultees were in summary:

Option 1

5.17 The Environment Agency (EA) questioned why a short term option was being considered. Concerns over the impact of the scheme on designated sites and loss of vegetation at Air Balloon were highlighted. Despite these concerns it was agreed that the option should be considered for further assessment.

Option 2

5.18 Concerns were expressed over the potential impacts on designated sites and the loss of vegetation at Crickley Hill. Visual impacts of the grade separated junction, its proximity to Crickley Hill and its affect on the context of the designated sites on Crickley Hill were also highlighted. However, in principle, consultees accepted that the scheme had some merit and agreed that it could be considered for further assessment.

Option 3

5.19 The EA voiced serious concerns over the need for de-watering during construction and post construction and on the potential for pollution of the aquifer. These were confirmed at a subsequent meeting with the EA in February 2002. They did accept, however, that pollution control equipment would be incorporated in the scheme (as with all options considered). They were concerned over effects on groundwater, springs and the River Churn. They stated that significant assessment work would be required if this option were to be taken forward. English Nature voiced concern over possible impacts on two SSSIs. Other concerns were the visual impact of the portal and link roads. Despite these concerns it was agreed that this option should be considered for further assessment.

5.20 The results of the second meeting with local authorities in summary were:

Option 1

5.21 Concerns over the short-term nature of this option. Issues relating to archaeology, ecology, landscape and impact on the context of National Trust land were particularly highlighted.

Option 2

5.22 Concerns over landscape impact, archaeology and the two additional lanes down Crickley Hill, loss of vegetation and impacts on the setting of Crickley Hill (Archaeology, National Trust and Ecology) were highlighted. Access to Cold Slad Lane and Grove Farm was also a concern.

Option 3

5.23 This option resulted in significant discussion and many concerns were raised. Cotswold District Council thought this to be the best option. Concerns over safety/accidents within the tunnel were also highlighted.

5.24 It was agreed that all three options should be considered for further assessment.