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Related pages

• 1 introduction
• 3 the principles of the dbfo contract
• 3 the principles of the dbfo contract
• 4 payment mechanism
• 5 technical requirements
• 6 timetable and procedure
• 7 prequalification assessment
• 8 information required from candidates for prequalification
• 9 responses and enquiries
• Appendix a a249 stockbury (m2) to sheerness dbfo project
• Appendix b payment mechanism
• Appendix c
• Appendix d draft agreement summary

A249 Stockbury (M2) to Sheerness DBFO Contract

APPENDIX A A249 Stockbury (M2) to Sheerness DBFO Project

1 Description of Project

1.1 The Project Road comprises the A249 Trunk Road from its junction with the M2 near Stockbury in Kent to Sheerness on the Isle of Sheppey. The DBFO Project also includes a Firm TPI Scheme, the A249 Iwade Bypass to Queenborough Improvement.The A249 and the A249 Iwade Bypass to Queenborough Improvement are shown in Figure 1 of this appendix.

1.2 The A249 Trunk Road runs from junction 5 of the M2 to the docks entrance at the Port of Sheerness and forms the only road link between the mainland and the Isle of Sheppey.

The extent of the Project Road excludes the roundabout at junction 5 of the M2 but includes the roundabout at the entrance to the Port of Sheerness.

The southern portion of this road, from the M2 to the crossing of The Swale at Kingsferry, comprises a dual 2 lane carriageway road, which was relatively recently constructed, being first opened to traffic in 1996. This section of road is of concrete construction.

This newer portion of the road passes under the M2 Stockbury viaduct, just to the north of a roundabout connecting the M2 slip roads to the A249. It then passes through two grade separated interchanges, one at the A2 crossing, and the second just north of this at Bobbing. This second junction forms a link into the industrial area to the north of Sittingbourne.A further grade separated junction is located at the crossing of the B2005 near Iwade, before the newer construction terminates at a roundabout on the south side of The Swale crossing at Kingsferry. The total length of this 'new' dual carriageway road is approximately 9km.

Beyond this roundabout, the road crosses The Swale on a lifting bridge, which also carries the only railway link from the mainland to the Isle of Sheppey. It then crosses open marshland for a distance of some 2.5km to a roundabout at the junction of the B2231 at Cowstead Corner. This section of road is single 2 lane carriageway with hard strips.From Cowstead Corner, the road becomes single 2 lane carriageway with no hard strips connecting with a further roundabout at the southern Queenborough junction.

From this roundabout to a point on the outskirts of Sheerness, a new alignment was constructed in approximately 1982 (the Queenborough Bypass). This is again a single 2 lane carriageway with hard strips, passing over the railway line on a long viaduct.

Beyond the roundabout at the northern link to Queenborough, the road returns to a single 2 lane carriageway without hard strips, on an original alignment through the semi-urban outer industrial area of Sheerness. The A249 terminates at a roundabout at the entrance to Sheerness Docks.

The total length of the A249 Trunk Road is approximately 17km.

1.3 The A249 Iwade Bypass to Queenborough Improvement is the last of four schemes to improve the A249 between the M2 and the port at Sheerness. The improvement will provide a new dual carriageway road 5 km long between the end of the Iwade Bypass and Queenborough and will include a new high level crossing of The Swale.

2. New Construction

2.1 Estimated Cost

The estimated construction costs of the A249 Iwade Bypass to Queenborough Improvement are given in Table 1 and are based on the level of design work completed to date.

Table 1: Estimated Construction Costs of the A249 Iwade Bypass to Queenborough Improvement at Q1.01 prices.

Figures exclude VAT and land costs

2.2 Scheme History

The identified scheme has been prepared to the timetable given in Table 2

Table 2: Timetable for the A249 Iwade Bypass to Queenborough Improvement

2.3 Design Agent

The Agency's Design Agent for the A249 Iwade Bypass to Queenborough Improvement is Mott MacDonald

2.4 Scheme Specific Information

2.4.1 The main engineering and environmental constraints and features of the existing design are set out in the following sections. Additional information is included in the deposit documents.

2.4.2 A list of agreements and commitments to third parties for the scheme will be included in the Tender Invitation Documents.

2.5 A249 Iwade Bypass to Queenborough Improvement.

Refer to Figure 2 of this appendix.

The proposed scheme provides a limited movement two level junction at the northern end of the Iwade Bypass from where the dual carriageway is to extend over a new fixed bridge crossing of The Swale.

The new bridge, which will be 1.27 km long, will rise to a height of 34.7m above The Swale. This will provide 29m clearance for shipping above high water level and also give the required clearance over the existing approach to Kingsferry Bridge on the south side and the railway on the north.

The route then joins the line of the existing A249 as far as the junction with Ferry Road, before moving away to a new roundabout at Cowstead Corner. A section of new local road will be constructed alongside the new Trunk Road to maintain a link between Kingsferry Bridge, which will be retained, and Cowstead Corner for local traffic movements. This link road will provide for pedestrians and cyclists, as they will not be permitted to use the new bridge crossing. The new A249 dual carriageway will then continue to the south of Queenborough Road, via a roundabout at Neatscourt to cater for a proposed development, to a new signal controlled junction with Main Road at Queenborough. From here, the Trunk Road will narrow to a single carriageway to tie into Brielle Way.

Design speed for the dual carriageway will be 120kph, speed limit 70mph. The Trunk Road between Neatscourt roundabout and Brielle Way will have a design speed of 85 kph, 50 mph speed limit.

The proposed scheme has been designed to:

• limit disturbance to flora and fauna;
• minimise land take as far as possible in protected areas;
• provide compensation land to replace that taken by the scheme (this is not part of DBFO Project);
• create new wildlife habitats;
• reduce visual intrusion by utilising high quality bridge design;
• provide new pedestrian and cycle routes;
• provide new drainage systems to avoid pollution;
• reduce noise levels by moving the road away from residential properties where possible and by providing noise barriers, including earth mounding; and
• minimise light pollution.

To the knowledge of the Agency, there are no known archaeological sites of national or regional significance within the road corridor, however, it is intended that further investigative work will be undertaken by the DBFO Co.

The proposed scheme is within the North Kent Marshes and encompasses three Sites of Special Scientific Interest: South Thames Estuary and Marshes; Medway Estuary; and The Swale. The North Kent Marshes have been identified as being of national and international importance as a habitat for birds, plants and invertebrates, and have accordingly been designated as a Special Protection Area (SPA) and a Ramsar wetland site.

In order to minimise landtake within the SPA between the Iwade Bypass and Cowstead Corner, narrower verges and central reservation are proposed on the new dual carriageway, and the existing road corridor will be used.

Other measures proposed to restore the ecological value will include the use of special grass seed mixes on the verges and embankments and the creation of open water ditches.

The new drainage will be kept completely separate from the sensitive marshland system, with outfalls into West Minster Drain in the north and The Swale in the south via suitable pollution control measures and valves.

All the public utility services to the Isle of Sheppey cross The Swale at or close to Kingsferry Bridge, and thus any new road connection is likely to have a significant effect on existing services.

A decision as to whether the existing A249 and Kingsferry Bridge will be detrunked when the new bridge is complete has yet to be made.

3 Operation and Maintenance

3.1 The DBFO Co will be responsible for all maintenance operations on the Project Road. This includes capital, routine and winter maintenance on the A249 from the M2 to Sheerness. This is shown in Figure 1 of this appendix. The Agency's requirements will be set out in the Tender Invitation Documents.

3.2 The existing Maintenance Agent for the Project Road is W S Atkins Transport Engineering and the Term Maintenance Contractor is Carillion.

3.3 Currently, the Project Road is the responsibility of the Kent Police based at Maidstone.

3.4 Details of the existing road are as follows:

The A249 from the M2 and including the Iwade Bypass is subject to national maximum speed limit but northwards of this the speed limit varies between 50 mph and 30 mph.

3.5 The following table, Table 3, lists both Agency structures on the Project Road and structures on the Project Road that are the responsibility of others.

Table 3: Structures on the A249

The junctions on the A249 are grade separated between the M2 junction 5 and the roundabout on the south side of Kingsferry Bridge and are at grade between Kingsferry and Sheerness.

3.6 There are no communications on the Project Road.

3.7 There are three Sites of Special Scientific Interest through which the Project Road passes.

4 Traffic Data

The existing traffic flows on the Project Road are shown in Figure 3 of this appendix. Where scheme forecasts are available the information is included with the Environmental Statement, see deposit documents.

5 Deposit Documents

Deposit Documents are available on CD ROM from the address at Section 9.5

1. A249 Iwade Bypass to Queenborough Improvement - Environmental Statement
   • Volume 1 Statement and Non-Technical Summary
   • Volume 2 Part 1 Air Quality
   • Part 2 Cultural Heritage
   • Part 3 Ecology and Nature Conservation
   • Part 4 Landscape Effects
   • Part 5 Agriculture
   • Part 6 Traffic Noise and Vibration
   • Part 7 Pedestrian, Cyclist, Equestrians and Community Effects
   • Part 8 Water Quality and Drainage
   • Part 9 Policies and Plans
   • Addendum to Environmental Statement
     
     
2. A249 Iwade Bypass to Queenborough Improvement - Scheme Orders
   1. The A249 Trunk Road (Iwade Bypass to Neatscourt Roundabout and Bridge) Order 2000
   2. The A249 Trunk Road (Iwade Bypass to Neatscourt Roundabout) (Side Roads) Order 2000
   3. The A249 Trunk Road (Iwade Bypass to Neatscourt Roundabout) (Side Roads) (No. 2) Order 2000
   4. The A249 Trunk Road (Iwade Bypass to Queenborough Improvement) (Slip Roads) Order 2000
   5. The A249 Trunk Road (Iwade Bypass to Queenborough Improvement) (Detrunking) Order 2000
   6. The A249 Trunk Road (Iwade Bypass to Neatscourt Roundabout) Compulsory Purchase Order (PS No. 21) 2000
   7. The A249 Trunk Road (Iwade Bypass to Neatscourt Roundabout) Supplementary Compulsory Purchase Order (PS No. 22) 2000
   8. The A249 Trunk Road (Neatscourt Roundabout to Queenborough Improvement) Order 2001
   9. The A249 Trunk Road (Neatscourt Roundabout to Queenborough Improvement) (Side Roads) Order 2001
   10. The A249 Trunk Road (Neatscourt Roundabout to Queenborough Improvement) Compulsory Purchase Order (PS No. 4) 2001
   11. The A249 Trunk Road (Neatscourt Roundabout to Queenborough Improvement) Supplementary Compulsory Purchase Order (PS No. 5) 2001
   12. (DRAFT ONLY) The A249 Trunk Road (Iwade Bypass to Queenborough Improvement) Prohibition of Certain Classes of Traffic and Pedestrians Order 2000
   13. (DRAFT ONLY) The A249 Trunk Road (Neatscourt Roundabout to Queenborough Improvement) 50 Miles Per Hour Speed Limit Order 2001 & Prohibition of Left and Right Turns Order 2001
       
       
3. A249 Iwade Bypass to Queenborough Improvement - Public Local Inquiry Document (Inspector's Report)
4. A249 Iwade Bypass to Queenborough Improvement - Secretary of State Decision Letters

Figure 1: A249 Stockbury (M2) to Sheerness DBFO - Extent of Project Road

• Figure 1 (11.7MB PDF)

Figure 2: A249 Iwade Bypass to Queenborough Improvement

• Figure 2 (1.4BM PDF)

Figure 3: Existing Traffic Data

• Figure 3 (50KB PDF)