Traffic Tunnels under Shooters Hill

Traffic tunnels seem to be in vogue at the moment, whether it be the proposed Silvertown tunnel or the Mayor of London’s proposals to put stretches of the South Circular Road underground and to dig an Inner Ring Road tunnel round central London. This despite evidence from the 2011 census that car ownership in London is dropping, and research showing that building new roads generates more traffic.

Shooters Hill hasn’t been immune to tunnel planners’ dreams. An early proposal is included as an appendix to a slim 1947 monograph “Road Works at Shooters Hill, Kent, 1816”, by F.C Elliston-Erwood in the Greenwich Heritage Centre’s search room. Frank Elliston-Erwood, who lived on Shooters Hill, was a distinguished local historian. He was at different times president of the Greenwich and Lewisham Antiquarian Society and twice president of the Woolwich and District Antiquarian Society. He was a member of the WDAS for 70 years, first joining as a teenager and continuing until his death in 1968. One of his interests was the New Cross Turnpike Trust, and it was from their minute books that he extracted the information for his paper about road works on Shooters Hill.

The paper is mainly about how the New Cross Turnpike Trust tried to create employment in the economic depression which followed Wellington’s victory at Waterloo and the end of the Napoleonic Wars. It was “a period of commercial and industrial upheaval, coupled with misery, poverty and unemployment”. The Trust decided to allow £1000 out of their tolls at a rate of £50 per week to employ as many poor men as they could at a maximum wage of 10s (50p) a week in work such as the “the digging or quarrying of gravel or stones” and “the levelling or reducing of hills”. On Shooters Hill they moved gravel from the steeper parts and deposited it in hollows to smooth out the incline. The result can still be seen, for example on the western side of the hill on the road opposite Craigholm where the pavement rises above the road following the original slope of the hill. Similarly on the eastern slope there is an embankment on the Oxleas Wood side of the road.

The map and plan at the top concludes the paper. It shows a proposal for a road that bypasses the steep top of the hill, running parallel to Shooters Hill but on the Eltham side of Severndroog Castle. It was planned to run through a deep cutting and about 400 yards of lamp-lit tunnel. Needless to say the proposal was never implemented. The author of the plan clearly liked his pubs – the map includes the Bull, the Red Lion and the Fox and shows the bypass heading towards the Green Man in Blackheath. The Fox was the old Fox under the Hill, which subsequently was moved further down Shooters Hill Road.

A more recent proposal for a Shooters Hill tunnel was considered as one of the options for a new Thames Crossing which Transport for London consulted about last year. Option D6 in the Assessment of Options Report was for a Woolwich Tunnel joining the South Circular to the North Circular.  The proposal is complicated by the presence of other tunnels in the vicinity – the Woolwich Foot Tunnel and Cross Rail, not to mention the DLR, so it would have to be a deep tunnel underneath all the others. Also the steep slope up from Woolwich towards Shooters Hill makes it difficult to start a tunnel close to the river, leading to the proposal shown below with a tunnel entrance all the way up at Eltham Common. This means that the tunnel would be some five or six kilometres in length, the longest road tunnel in Britain.

The South Circular at Eltham Common where the entrance to the tunnel would be is shown below. Just imagine this green scene replaced by a huge, 4-lane tunnel portal, like the entrance to the Blackwall Tunnel. Fortunately the proposal was discounted. There were a number of factors leading to the decision not to take this option further. It was felt that Well Hall Road would become a bottleneck, limiting the tunnel’s capacity and reducing journey time improvements. It would be difficult to upgrade Well Hall Road because it is residential and has houses on both sides. Also it was “unlikely that the scheme could be built without negatively impacting on the housing lining the A205 through Eltham”.

The tunnel was felt to be too far away from the river to benefit residents closer to the Thames, for example in Woolwich, and would not connect to the major roads along the south side of the river, and so would not contribute to development along the river. Then there was the possible cost of up to 6km of bored tunnel, estimated at £1.5-2 billion. All things considered a Woolwich Tunnel doesn’t make sense.

The TfL East London River Crossings: Assessment of Options document mentions, very briefly, another tunnel under part of  Shooters Hill. Section 6.234 on page 167, which discusses the proposal for a “local” bridge at Gallions Reach, says (my emboldening):

In the longer term, any fixed link provides the potential for the highway connections to be amended or improved over time, to best suit the prevailing traffic and regeneration needs of the area. For example, the connections to the strategic network could be improved in the long term, such as through the provision of a direct link to the North Circular together with a tunnel south to the A2. This could potentially address the local concerns about traffic on residential roads in Bexley by providing an effective by-pass, while delivering large journey time benefits to the wider area by providing a more easterly strategic orbital route. In time this could replace the Blackwall corridor as the main strategic route, and deliver benefits to regeneration in the Lower Lea Valley.

So once any Gallions Reach crossing is in place any changes in traffic level – the then prevailing traffic – could lead to the building of additional roads, such as one through Oxleas Wood, to create the major easterly strategic route.

Concern about increased traffic levels on residential roads south of the river as a result of a new river crossing at Gallions Reach were heightened by a report produced for the London Borough of Newham on the Economic Impact of Gallions Reach Crossings. It presents the results of traffic modelling of different options for a Gallions Reach crossing, generated using  Transport for London’s highway model of East London known as ELHAM. Amongst the results was a map showing northbound traffic flows in 2021 assuming a bridge was built at Gallions Reach. The snippet below shows the area south of the river.

It’s a difficult map to read, and it took me some time to work out what it was saying. The green blocks represent high traffic flows, and the large block in the middle of the picture is the Gallions Bridge itself. Working southwards from the bridge, the high traffic flow roads seem to be: Western Way, down to the gyratory near Plumstead Station, then up residential Griffin Road, across Plumstead Common on Warwick Terrace and then along Swingate Road, Edison Lane, Wickham Street to meet Bellegrove Road: none of these roads is designed for large traffic flows. To the west there are also high flows  in Plum Lane, and to the east large flows down narrow Knee Hill. And, as usual, the modelling doesn’t cover what would happen if one of the other Thames crossings was blocked, which seems a common occurrence at the moment, and all the traffic heading down the A2 to the Blackwall Tunnel turned off to Gallions Reach.

There is no analysis of the impact and costs of a tunnel from Gallions Reach to the A2 in the Assessment of Options document. As can be seen on the snippet from cbrd.co.uk web site’s superb UK roads database below, if the tunnel went from Gallions Reach all the way to the A2 at Falconwood it would have to be longer than a 5-6km tunnel from Eltham Common under the Thames, and well over twice the length of the UK’s longest road tunnel the 3.2 km Queensway tunnel in Merseyside. If it were a bored tunnel it would cost more than the £1.5-2 billion estimated for a Woolwich tunnel. Should a cheaper construction option be chosen then people’s homes in Plumstead and ancient Oxleas Wood would be threatened yet again.

If the “prevailing traffic” following development of a Gallions Reach bridge led to a revival of plans for a road to the A2, along the lines of Ringway 2, one of the consequences would be the massive road junction shown below – splat on top of Woodlands Farm. It has been suggested that a Transport for London document revealed by a recent freedom of information request shows that a road through Oxleas Wood is included in one of the traffic scenarios that TfL are modelling for the Mayor of London’s Roads Task Force.