Roscommon Way Extension Phase 1 Roscommon Way Scheme Overview
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Roscommon Way Extension Phase 1 Roscommon Way Scheme Overview N N Northwick Road Roundabout Basildon Borough Council Site of Special Scientific ‘Untidy Industries’ area Interest (SSSI) Wildlife relocation area New Canvey Island Youth Football Club RSPB Wildlife relocation area Existing access to the Morrison superstore and Roscommon Way other land maintained Extension, Phase 1 Orchard Land East of England Wildlife relocation area Development Agency Ditch Enhancement East of England Development Agency Ditch Enhancement A new bridleway along the whole extension Wildlife crossing Charfleets Roundabout Fleet Roundabout for access to and from Charfleets Dyke to avoid a complex crossing Charfleets Industrial Estate Bridge of pipelines and a dyke An insect friendly habitat has been created on The Orchard Land Sluice Farm Footpath FP16 Dyke Bridge re-routed a short distance to a safe crossing point Road raised Haven Road ‘T’ junction (upgraded to remain ‘dry’ in to a roundabout in Phase 2) an emergency This map is based upon Ordnance Survey material with the permission of Ordnance Survey on behalf of the Controller of Her Majesty’s Stationery Office © Crown copyright. Unauthorised reproduction infringes Crown copyright and may lead to prosecution or civil proceedings. Essex County Council 100019602 2011 Scheme background Objectives of the scheme Canvey Island lies in the south of Essex, 25km east of London on the Thames Estuary and within the Thames • Regenerate the local economy and environment. Gateway Regeneration Area. The road network on the island relies on two main routes, the A130 and the • Ensure a safe route in an emergency, particularly B1014, that link its town centre with the mainland. in the event of a major flooding event. Phase 1 of the scheme has extended Roscommon Way from Northwick Road to Haven Road. This has • Provide commercial and industrial traffic an included 1.5km of new highway, 0.8km of which is dual alternative route away from residential areas. carriageway, two new roundabouts and a ‘T’ junction. • Improve accessibility, especially to the southern Phase 2 will extend the route further, stretching from side of Charfleets Industrial Estate with a new Haven Road to Thorney Bay Road. access point. Construction - Highway The Roscommon Way Extension lies at the south-west corner of Canvey Island, within a corridor that is either post-industrial or undeveloped. The area is a mix of commercial, ecological, light industrial, residential and fuel storage areas. The scheme consists of: • 700m dual carriageway Dual carriageway begins • 650m single carriageway • 2 new bridges • 2 new roundabouts The road extension was conceived as a new route enabling much of the Bridleway near Superstore (looking south) existing traffic to avoid using Canvey Way and Long Road. The highway design provided a solution for linking Charfleets Industrial Estate, Haven Road and Northwick Road. The highway design involved a number of engineering disciplines including; • Drainage Design (1,500m3 of drainage) • Geotechnical Design (30,000m3 of excavations) Aerial shot (Northwick Roundabout) • Surfacing (23,500m2 of surfacing) • Embankment Design (70,000m3 of earthworks material imported to embankments) • Bridleway along entire length of the road In total over 125,000 man hours were deployed, with no reported accidents! Underground drainage storage tanks Wick Drain construction Fleet Roundabout (foreground) Charfleets Roundabout (background) Construction - Bridges The works at Roscommon Way cross seven drainage ditches, two water- courses and three high pressure gas and oil pipelines. These crossings were achieved by the construction of 11 structures of three distinct types and by diverting one of the pipelines. The three types of structures used were bridges, box culverts and underground protection slabs. The new route alignment crosses two water-courses between Fleet Roundabout and Haven Road, namely Sluice Farm Dyke and Charfleets Dyke, using two single span bridges. The structures have a clear span of seven metres and are constructed from in situ reinforced concrete. They are supported on 350mm square precast reinforced concrete driven Sluice Farm Dyke Bridge piles 19 metres below the existing ground level. Construction of the bridges also includes mammal ledges to provide a safe dry crossing point under the structure for the various mammals which can be found in the area. Piling in action Charfleets Dyke Bridge Completed Sluice Farm Dyke Bridge Abutment and wingwall construction Construction - Flood Relief Features Foundation construction Pre-cast culvert unit Seven precast concrete box culverts with in situ reinforced concrete headwalls and wingwalls are used to provide safe crossing points for wildlife and a clear channel for the following drainage ditches: Wingwall reinforcement • Holehaven A • Holehaven B • Romainville • Sandhurst A • Sandhurst B • Ormsby A • Ormsby B The structures all have a clear span of three metres and have enough clearance to accommodate the 1 in 1000 year design flood Wingwall construction level. Environmental considerations have been taken into account in their construction with all culverts having a mammal ledge to provide a safe dry crossing point for wildlife. The wingwalls at Holehaven A and B drainage ditches are finished with a ridged pattern to assist in the establishment of micro environments for insects within the Site of Special Scientific Interest (SSSI). Completed culvert with mammal ledge Construction - Pipeline Diversion The route for the Roscommon Way Extension required the new road to cross over three gas and oil pipelines at three separate locations. This was achieved by using two pipeline protection slabs and by diverting one of the pipelines. Welding Diverted pipeline Auger boring Pressure testing The British Pipeline Agency Ltd (BPA) pipeline at the Haven Road end of the scheme was not carrying any product at the time of construction and could therefore be diverted instead of a further protection slab being constructed. To ensure the long term structural integrity of the pipeline and future proof (for Phase 2) the installation the 12” diameter pipe was constructed from a thick, heavy duty walled pipe approximately 120 metres in length. Preparing to bore Construction - Pipeline Protection Two voided protection slab structures are utilised at the crossing points of the Holehaven and Romainville pipelines. These are essentially buried structures which are not visible from above ground and have voids formed by using Reinforcement cage within pile expanded polystyrene to reduce the overall weight. The slabs are supported on 750mm diameter bored cast-in-place reinforced concrete piles, which vary in length depending Piling rig on whether they made contact with the river terrace deposits or within the London Clay beneath this. Where it was possible to found the piles within the river terrace deposits, the piles are generally 19 metres in length. However where it was not possible to found the piles within the river terrace Piling auger deposits it was necessary to increase the pile length to approximately 38 metres. Romainville Way construction Holehaven construction Construction 1 Environment - Highway Land The area stretching from the Some areas of grassland have been allowed to become Northwick Road Roundabout tussock-like and appear unmanaged. Cutting the grassland only once per year and removing the cuttings stops the very competitive Many of Britain’s wildflower species have declined through use of farming chemicals since the species of grasses from taking over. They form an important area 1960s. Wild flowers provide shelter and food for many invertebrate species. Most of the flowers you to the Sluice Farm Dyke, in for invertebrates, small mammals and reptiles to forage and live. can see growing along the road have been grown from seeds collected before the road was built! Roscommon Way passes through one of England’s Rough Grassland Wild flower meadow particular, was within a Site most important invertebrate sites – the Canvey Wick Site of Special Scientific Interest (SSSI). Essex County Council worked closely with their of Special Scientific Interest environmental consultant Mouchel, and Natural England to ensure that work on Roscommon Way was undertaken sensitively to maintain importance (Canvey Wick SSSI) and host of the site to many invertebrate species. An eye catching and unmistakable butterfly, the Peacock Invertebrates are integral to the ecosystem, to a range of rare invertebrate Gatekeeper Butterfly (Pyronia tithonus) can be seen throughout the summer feeding on nectar rich providing essential food to birds and mammals, flowers in Britain’s gardens and parks before winter hibernation. The four eyespots on the wing resemble the as well as other ecological, agricultural and N Also known as the Hedge Brown, the Gatekeeper Butterfly is so tail feather pattern of the peacock and are there to scare technological benefits. species such as the Shrill named dueCanvey Roadto its frequent occurrence near field gates, field away predators. A number of features have been designed to Northwick Road Roscommon Way margins and hedges. The adult Gatekeeper has a short proboscis/tongue, so can often been seen feeding on the support this ecosystem. In some areas next to the Northwick Road shallow flowers of the blackberry. The male possesses a dark Peacock Butterfly (Inachis io) Carder Bee and Scarce Roundabout Northwick Road St Marks Road roadside you will see what appears to be piles of patch