The M4 in Wales
The M4 history probably started as early as 1823. At that time steam packets were plying between Milford Haven and Southern Ireland, and the Postmaster General had appointed Thomas Telford to advise on measures for improving the mail coach route between London and Milford. The main problem was the provision of the crossing of the Severn Estuary, to replace the long diversion through Gloucester or use of the Aust to Beachley Ferry.
Telford recommended a crossing from Uphill Bay on the Somerset side, to Sully Island. This was rejected, but Telford quickly returned in 1824 with a proposal for a suspension bridge, more or less on the Severn Bridge line. Two major reports in 12 months!
Nothing was done, but there were improvements to the ferry, and the railways were growing in importance until they were the dominant mode of transport in 1845. The Severn Rail Tunnel was opened to traffic in 1886.
It was at the beginning of the last century that the development of reliable petrol engines began to highlight once again the need for road improvements. The 1914/1918 war then intervened, but in the early 1920’s the Chepstow Urban District Council took the initiative and convened a meeting of neighbouring local authorities. This meeting considered the construction of a Severn crossing to ease congestion and delays on the A48 within Chepstow itself, and also across the historic cast iron bridge over the River Wye to the north of the town (constructed in 1816).
Also, at about this time, the then Ministry of Health set up the South Wales Regional Survey Committee, which in 1921 reported in favour of a bridge across the estuary near Chepstow. The improvement of the road between Bridgend and Llantrisant was also suggested to take account of changes in the location of industry and population.
In 1935 Gloucestershire County Council appointed Mott, Hay and Anderson as Consulting Engineers, and jointly with Monmouthshire County Council, promoted a Parliamentary Bill to obtain powers to build the bridge over the estuary, with 75% of costs being met by the Ministry of Transport from the Road Fund. The Bill was rejected by a Select Committee of the House of Commons in 1936. The Great Western Railway Company had strongly opposed the Bill!
In 1938 the County Surveyors Society and the County Councils Association, put forward a proposal for a National system of 1,000 miles of new road, specifically constructed and restricted for motor vehicle use. This included the Severn Crossing, and a route across South Wales clearly intended to serve the mouth of the Welsh valleys.
The Ministry were not so forward looking. Experience in the 1920’s and 1930’s had shown that County Councils could not face the burden, which the provision of an adequate National highway system would entail. Therefore the 1936 Act of Parliament introduced the Trunk Road concept of roads built and maintained by Central Government. This included the Severn Crossing and an A48 route around the coast, but there was no road through Llantrisant to encourage development in the valleys as well as on the flat coastal region.
Then came the 1939/45 war. During this period there was only limited planning for the trunk road network in Wales, with action taking place following the war. The policy was to provide piecemeal improvement of local roads.
The County Surveyors Society and the County Councils Association continued to press for a National system of motorways, and to stress the importance of grade separation, the removal of pedestrians, and the limitation of access. Eventually they were invited to submit further details, including recommendations, through the Divisional Road Engineer to the Ministry, on a County by County basis. In 1943 the County Surveyor of Glamorgan, after consultation with Monmouthshire, put forward proposals for a high standard dual carriageway, substantially following a line as now built. Again this proposal had limited success!
In 1945 the Ministry took over responsibility for the Severn Bridge and appointed Freeman Fox and Partners, Consulting Engineers, as well as Mott, Hay and Anderson, to prepare National proposals. Then, in 1946, the Ministry published a 10year National plan, to be developed in three stages. For two years, arrears of maintenance were to be dealt with, and certain schemes which had been suspended due to the war, were to be given priority. The Severn Bridge and a high speed dual carriageway from the Bridge to Tredegar Park , Newport, were included.
After this post war flurry of paper, little happened over the next ten years. The dualling of the Neath Bypass between Baglan and Earlswood was completed in 1956, and the Earlswood to Lonlas section in 1960. The A48 Port Talbot Bypass between Groes and Baglan also opened to traffic in 1966).
The Welsh Office became responsible for trunk roads in 1964 and in the following year a White Paper ‘Wales the Way Ahead’ was published by the Government. This document included a comprehensive review of the need for economic and other development in Wales and set out long term proposals for accelerating the enhancement of employment opportunities and social improvements.
Subsequently the Secretary of State also announced that the Government had decided to take over and construct as soon as possible, an extension of the M4 from Tredegar Park to Bridgend, a route for which had already been identified and protected by Glamorgan County Council.
This positive undertaking is probably the most clearly identifiable point at which the Government became irretrievably committed to the extension of the M4 beyond the terminal at Tredegar Park, which had originally been seen as adequate by the Ministry of Transport in London. A similar strategy had been adopted for terminating the M5 at Exeter and improving the A38 to dual carriageway standard to Plymouth. The contemporary strategy for the A48 in South Wales included bypasses for Cowbridge and Bridgend, together with all the other major built up areas, as far as the western side of Pontardulais. The Glamorgan County Council had carried out extensive preliminary investigations and routes for all the bypasses had been identified and protected.
In March 1968 the M4 Tredegar Park to St Mellons and M4 Pontardulais sections, were added to the Trunk Road Preparation Pool. The Pyle Bypass section followed in 1969, and the Bridgend Northern Bypass in 1970.
By 1970 therefore, the Welsh Office had adopted a high standard dual carriageway road across South Wales, terminating at Pont Abraham to the west.
Although the strategy for the Cardiff area provided a very useful radial route serving the rapidly developing Llantrisant area, arguments and difficulties were continuous, as the planning procedures involved unfolded. In 1971 the Secretary of State abandoned this strategy, and immediate action commenced on a Cardiff Northern Bypass. The County Council had protected a route from the early 1950’s!
Administration of the M4 Schemes
In 1970 serious consideration was given to the setting up of a Road Construction Unit within Welsh Office, to supervise the ten M4 schemes still to be completed. Distribution of work between South and North Wales, and the timing of the individual schemes, gave rise to serious practical difficulties. It was therefore decided to split the work between Local Authorities and Consulting Engineers, under the overall supervision of Welsh Office staff.
Before Local Government Reorganisation in 1974 Glamorgan County Council was the Agent for the Coryton to Capel Llanilltern, Capel Llanilltern to Pencoed, and Pencoed to Stormy Down (Bridgend Northern Bypass) sections. Swansea Borough Council, and subsequently West Glamorgan County Council, were Agent Authority for M4 Morriston Bypass up to and after its completion.
Order Procedures and Construction Time-Tables
Although the various lengths of the M4 are covered in more detail later, it is worth noting here the extent of opposition to the four concurrent sections between Coryton and Groes.
Commencing to the east, the Coryton to Capel Llanilltern section attracted much opposition. Although a route had been included in the Development Plan for many years houses had been built adjacent to the proposed boundaries, particularly in the Morganstown and Radyr areas. Many route alternatives were presented at the Public Inquiry into the Line Order.
The Capel Llanilltern to Pencoed section was probably made more controversial because of proposals for a Llantrisant New Town, and also for a large new sewage disposal works. The June 1972 Inquiry was delayed from its publication in November 1970 due to the additional complication of the proposed New Town. There were two further delays whilst the Inspector closed the Inquiry to await new evidence.
The Pencoed to Stormy Down section (Bridgend Northern Bypass) line had not been through the full development plan process, although it had been formally protected by the Planning Authority. The Consulting Engineers therefore started with a much more open situation.
Although there were objections, including one for an additional junction (at grade if grade separation proved uneconomic!) from the County Council, the main criticisms related in particular to footpath diversions. Following the Line Order Inquiry the route was finally confirmed as published.
There was considerable objection to the Stormy Down to Groes proposals. A line for an all purpose Bypass had been included in the Glamorgan Development Plan for many years, and as in the Cardiff area, housing, in this case both Council and private, had been built up to the proposed boundaries.
Immediately before this Inquiry the Government had accepted recommendations made by the Urban Motorways Committee, with particular emphasis placed on putting people before cars. The Secretary of State therefore decided to withdraw the published proposals for an interchange at North Cornelly. There was also considerable public objection to the proposed line at Cornelly, with pressure to move it further away from the houses, and to the proposed demolition of the Round Chapel at Groes and the masonry houses in Groes village. It is of interest that John Morris. Q.C. representing the local interests of the District Council, eventually became the Secretary of State for Wales.
The Inspector accepted the line through Groes, but recommended that the line be moved further away at North Cornelly. The change would have resulted in considerable delay however, and because of the significant existing congestion at Pyle, and the urgent need to improve communications to Swansea and West Wales, the Secretary of State decided to adhere to the published line. The Round Chapel at Groes was carefully dismantled however, and re-erected at a new site in Port Talbot at a cost to the Welsh Office.
The Secretary of State also decided to move the North Cornelly Interchange further to the East, and following the making of the main orders described above revised orders were published to cover the affected lengths. A further Public Inquiry was needed.
Because various alternatives put forward at the Public Inquiries into the four schemes between Coryton and Groes affected adjacent schemes to varying degrees, the Secretary of State decided that all four schemes should be considered together as a complete route. The Inquiry reports were therefore considered together and decisions published concurrently. This created some difficulties for the Agent Authorities and Consulting Engineers involved, but hopefully reassured the public that the motorway was not being dealt with in isolated sections, and that a broad strategy had been in place.
Design and Construction
For detailed design and construction purposes, Local Government Reorganisation, which took place in 1974, had considerable effect. Originally Glamorgan County Council was the Agent Authority for all four sections of the motorway between Coryton and Groes, but following reorganisation the county was divided into three parts. This could have created considerable uncertainty and disagreement between all parties, but thanks to the excellent co-operation given by the three new County Surveyors and their Councillors in the South, Mid and West Glamorgan Authorities, the detailed design work was completed without any significant problems.
The statutory procedures had included a junction at Capel Llanilltern. As a consequence of the
removal of the Llantrisant Radial proposal however, it was logical to re-locate it to Miskin to the west. This could then provide more effective access for construction and permanent traffic to the local road network, and encourage development within the Llantrisant area.
The total Coryton to Pencoed length had been designed by the Glamorgan County Council Surveyor’s Department. Following reorganisation however the County Surveyor continued to manage the total design, but with staff loaned from South Glamorgan County Council, to finish the Coryton to Miskin details. South Glamorgan then supervised the Coryton to Miskin contract, and Mid- Glamorgan the Miskin to Pencoed length. Tenders for the two contracts were invited concurrently, with the Contractors given the opportunity to offer a discount should they obtain both. After consideration of the tenders, the cheapest solution was to award contracts to two separate contractors.
In 1976, at the peak of the motorway construction in Wales, monthly certificates totalled some £4 million in value, and employment at peak periods was almost 4,000. In 1977 Pontardulais Bypass was opened to traffic in the April, Tredegar Park in the October, and the two lengths between Coryton and Pencoed in the December. A total of 31 miles in eight months at a cost of £130million. 115 structures were built, not including culverts, 12million cubic metres of material was excavated and 10million cubic metres used in embankments. In total well over 1million trees were planted on the M4 in Wales.
Generally Welsh Office applied the standards laid down by the Department of Transport, but there were occasional exceptions such as: