In the post-war period, Western Avenue was allocated a high priority for scarce road improvement funds, and was progressively upgraded from its original S2/S3 configuration to D3 between Shepherd’s Bush and Denham. The dualling work was not especially sophisticated, generally just the reconstruction of the roadway within its existing boundaries and retention of the diamond-shaped roundabouts and uncontrolled junctions that were original to the road. It had been laid out, in the 1920s and 30s, with a right-of-way wide enough to accommodate dual carriageways, and generally either had service roads or space for them running parallel, so the project was not especially difficult.
The work appeared to proceed inwards from Denham, though some sections were built out of sequence. The most adventurous part of the project was the construction of the underpass at Hanger Lane, referred to at the time as a “flyunder”1.
Sections
The route was divided into numbered sections as follows2.
| Section | Description | Dualling |
|---|---|---|
| 1 | ||
| 2 | ||
| 3 | Alperton Lane to Hanger Lane, including widening of railway bridge at Park Royal station |
Hanger Lane underpass controversy
The Hanger Lane “flyunder” was, from the available documentation, considered something of a novelty at the time it was built. While the earliest stages of the motorway network were in planning and beginning to reach construction at this point, grade separation was still considered somewhat unusual, and in particular this project’s status as an urban grade separation scheme involving a cut-and-cover tunnel rather than a flyover made it virtually unique.
The project evidently did not progress smoothly, and there appears to have been an attempt to review the process after it had been completed. The results of this are held at a single file whose title includes the uncharacteristically direct words “lessons to be learned from the Department’s experience over the execution of the Contract”3.
The timeline appears to begin on 9 September 1958, when the MOT awarded the contract for construction of the underpass A.E. Farr Ltd. Farr subsequently built the underpass, but not to the MOT’s complete satisfaction, and for their own part were unhappy that their claims for additional payments were refused.
The key points of dispute appear to have been:
- The terms of the contract were such that Farr would be paid for excavating the exact volume of material needed to make a space for the underpass. It included no payments for any additional excavation around the outside of that space, but additional excavation was necessary; Farr’s claim refers to it as “working space”. This would have been space to build the walls and so on.
- On the basis that they had excavated more material than the contract envisaged, Farr made a claim for £123k more than originally agreed.
The matter went to arbitration in 1962. The arbitrator found that the contractors hadn’t needed to do nearly as much digging as they did, but they did need to do more than had been foreseen in the contract terms. They were awarded £171,954 plus 6% interest. The judgement was awarded in the House of Lords, so this was a reasonably high profile and acrimonious dispute.
From the MOT’s point of view, this had been a project run on a relatively new model, whereby a firm of engineering consultants had looked after what we would now call the “project management” side. This became a reaosnably common practice over the next couple of decades, as the level of direct management by MOT civil servants and engineers declined, and indeed it is the sole operating model for National Highways today.
At Hanger Lane, though, it was relatively novel, and as a result the consultants hadn’t adequately prepared the contract documents. They were sent out to tender while still full of provisional calculations and other errors, a fact that the MOT only became aware of when it was too late. The Ministry’s “lessons learned” were threefold: that they had to be careful who they got to draw up their contracts; that they had to be careful who they let their contracts to; and that they needed to maintain a close level of scrutiny over contractual proceedings even when handled at arm’s length.
References
- London – Fishguard Trunk Road A40: Western Avenue (3rd section) provision of dual carriageways between Alperton Lane and western end of approach to underpass at Hanger Lane, widening of Park Royal station railway bridge; held at MT 110/37 ↩︎
- ibid. ↩︎
- Hanger Lane Underpass: lessons to be learned from Department’s experience over execution of contract; held at MT 123/140 ↩︎