A138 Chelmsford - Replacement of Chelmer Viaduct
Maintenance Scheme
Part of our ongoing programme of work to maintain England's strategic road network
We are currently in the process of recommissioning a scheme consultant and unfortunately will need to revisit some of the previously obtained agreements and approvals as some may be time expired before works can commence. The implication of this is that site works can now not commence until late next year at the earliest and more likely will be delayed until spring 2014 to avoid ground working in areas subject to flooding during winter months.
The most optimistic timescale for completion of the new viaduct is by the end of 2015. This means that the existing structure will need to remain in service for longer than originally predicted. We continue to monitor the condition of the structure and have a number of concerns about its performance. In order to address these concerns we have commissioned some resurfacing and joint repair work this year that will reduce the effect of vehicle impact loading on the structure.
What is happening?
We propose to replace the existing A138 Chelmer Viaduct and River Bridge with a new structure.
When and where is this happening?
The development of the Chelmer Viaduct replacement project has taken longer than anticipated and as a result, it is now doubtful whether the scheme can be delivered within the time constraints of the existing planning permission. This is likely to further extend the period before the structure can be replaced.
Action is in hand to resolve the above issues and develop a programme for the scheme. In the mean time maintenance works and contingency strategies for the ongoing use of the existing structure have been put in place. Once clarity on the programme has been achieved, these pages will be updated accordingly.
The Chelmer Viaduct is located on the A138 near Chelmsford, Essex.
Why is this happening and what will it cost?
The A138 Chelmer Road is a heavily used transport link vital to the continued flow of traffic within Chelmsford. The existing Chelmer Viaduct is in a poor condition and is deteriorating further.
If no action is taken to repair or replace the existing viaduct then the A138 Chelmer Road could be subjected to traffic weight restrictions and possibly eventual closure.
How will the scheme be carried out?
The new structure would be constructed slightly to the east of the existing Viaduct and connect into the Army and Navy and Chelmer Village Way Roundabouts at either end. Once construction is complete, traffic would be transferred from the existing Viaduct onto the new structure. The existing Viaduct would then be demolished.
The A138 has been de-trunked, but we have retained responsibility for the viaduct until it has been replaced. We are responsible for providing a "like for like" replacement of the existing structure. However, in close liaison with Essex County Council and Chelmsford Borough Council, we have incorporated a number of improvements into the design.
The Viaduct structure will be constructed of "weathering steel" (unpainted) beams with a concrete deck on elliptical columns. The River Bridge will be constructed of "weathering steel" beams with an external concrete arch edging with an engraved stone inlay.
The solid reinforced concrete abutments will be faced in stonework. Culvert units are used to support the road near to the Army and Navy to allow flood waters to flow where headroom is too low for steel beams. Services including gas, water and telecommunications would be diverted and incorporated into the new viaduct
Public Art will be incorporated within the stone inlay to the external concrete arch edging at the River Bridge. Note that the design shown on the current drawings is illustrative; the final design will be developed by a public artist at a future date.
The scheme will incorporate:
- Three lanes of carriageway: two lanes running towards the Army and Navy Roundabout and one lane towards the Chelmer Village Way Roundabout
- A 3m wide shared footway/cycleway on the west side of the viaduct to improve the link across the structure. No footway or cycleway would be provided on the East side.
- A new footpath at ground level, adjacent to the new viaduct, to connect the Chelmer Village Way Roundabout with the riverside footpath network. The steps at the existing River Bridge that lead down to the riverside footpaths cannot practicably be replaced due to current requirements for ramped disabled access
- Safe access for future inspection and maintenance would be provided including dedicated vehicular access.
Existing Public Rights of Way would be maintained throughout the construction period. The proposals do not prevent potential future schemes at the Army and Navy Roundabout or for the Eastern Gateway Access Road.
How will this impact on my journey?
This scheme is still in the planning stages. We will add more information about how this project will impact on your journey when we are closer to construction.
What are the benefits?
This scheme will safeguard the A138 as a highway link, maintain safety and allow the ownership of the structure to be transferred to Essex County Council, who are the Highways Authority for the A138 Chelmer Road. The improved layout would improve queuing capacity on the viaduct towards the Army and Navy thereby reducing congestion at the Chelmer Village Way Roundabout.
How do I find out more information?
More information will be posted on this project page as it becomes available. You can subscribe to be alerted when updates are made.
If you have any queries about this project you should contact the Highways Agency Information Line by emailing ha_info@highways.gsi.gov.uk or calling 0300 123 5000.
| Activity | Date | Status |
|---|---|---|
| Finalisation of design and statutory procedures | Autumn 2011 | Complete |
| Official Journal of the EU (OJEU) advertisement | Late 2011 | Complete |
| Procurement Process | Early to Late Spring 2012 | Complete |
| Construction Starts | TBC | Planned |
| Construction Completed | TBC | Planned |
Leaflet
This leaflet summarises the need for the viaduct and outlines the alternatives considered and the proposals on which we would like your views.
An Environmental Impact Assessment has been undertaken for the Scheme and an Environmental Statement has been prepared. The scheme design incorporates many measures to reduce and minimise the effects on both the man-made and natural environment. The Environmental Statement describes the existing environmental conditions
and assesses the effects that the scheme would have on those environments.
Traffic
The "off-line structure" allows traffic to remain on the existing viaduct whilst the new viaduct is constructed.
There would be some temporary disruption to traffic whilst the new viaduct is connected to the roundabouts at either end. This is expected to be carried out over two weekends.
Construction
Construction is expected to take 18 months for the new viaduct. Once the construction is completed, traffic would be transferred onto the new structure. The existing viaduct would then be demolished over a period of 6 months.
Landscape and Visual Appearance
Significant Landscaping and planting works would be undertaken to replace the areas impacted by the Scheme and to screen the ends of the viaduct. The proposals include a distinctive river bridge with an arched elevation of cream concrete with a natural stone infill panel to each face of the river bridge, the panels would be engraved with a design to be developed by a Public Artist. The river piers are encased in stonework.
Water Environment
The viaduct is located on a functional flood plain. The new viaduct has been designed with open spans and a raised deck level to ensure that it does not impede water flows or increase risk of flooding elsewhere. The new embankments would reduce the area of land available for storing flood water. To compensate for this, the Scheme includes an equivalent volume of new flood storage by lowering ground levels within the footprint of the viaduct.
Drainage ponds would be provided to treat surface water runoff from the carriageway before discharge into watercourses. The ponds would also trap any pollutants in the event of a spillage on the viaduct.
Noise
During construction, every effort would be made to reduce the effects of noise on nearby properties. Once completed, a low noise material would be used for the new road surface.
Lighting
The new lighting to be installed on the bridge would be of a standard that would minimise light spill to the surrounding environment.
Ecology
The River Chelmer floodplain is designated as a Site of Importance for Nature Conservation (SINC). There are likely to be direct effects during construction of the viaduct and its operation from the loss of habitat under the new viaduct, such as loss of scrub and trees. However, the impacts would be offset by new planting, particularly within the area of the old viaduct which is to be removed.
A range of protected species have been recorded within the vicinity of the site, notably bats, otters and slow worms. Thirty-seven species of bird were recorded on site, including house sparrow, reed bunting, skylark, song thrush and starling. There are likely to be both direct and indirect impacts during construction and operation with the loss of habitat. Appropriate measures would be taken to ensure protected species are temporarily excluded from the construction site and new planting would replace habitat lost.
Options Considered Previously
A workshop was held in April 2007 to discuss the various options for the Chelmer Viaduct and River Bridge with representatives from:
- The Highways Agency - the owner of the existing structure
- Essex County Council - the Highways Authority to whom it is intended that ownership of the structure would pass on completion of the work
- Chelmsford Borough Council - the Local Planning Authority
- The Environment Agency - Consultee for Flood Issues
- AECOM (formerly Faber Maunsell) - the Highways Agency's consultant for the project
- Atkins - the Highways Agency's Maintaining Agent for East Anglia
The main options considered were :
- Option 1 - Repair and Refurbishment of the Existing Chelmer Viaduct
- Option 2 - On-line Replacement of the Existing Chelmer Viaduct
- Option 3 - Off-line Replacement of the Existing Chelmer Viaduct
The workshop concluded that 'Off-Line Replacement of the Existing Chelmer Viaduct' with demolition of the existing structure is the preferred option for the following reasons:
- Options 1 and 2 would result in significant disruption to traffic using the existing viaduct including the need to divert heavy vehicles onto alternative routes for the 18 month construction period. This would not be necessary for Option 3.
- The refurbished structure of Option 1 would retain the width and layout of the existing viaduct and would not therefore provide the opportunities to improve the traffic links, drainage, lighting and access for maintenance afforded by Option 3. It is noted that Option 2 could provide these opportunities for improvement .
- Options 2 and 3 would be newly built structures designed to have a life (with suitable maintenance) of 120 years. The refurbishment works of Option 1 would be expected to extend the life of the structure by 25 years or more due to the limiting condition of the existing structure.
- Option 3 would be the safest to construct as the majority of construction and demolition is remote from the existing highway. Options 1 and 2 would require working close to the travelling public throughout the construction period and are therefore considered less safe.
- Option 3 would be the most economical to construct and would have the shortest construction period (18 months).