From the highly skewed A428 dual carriageway bridge near Highfields Caldecote in the west to the huge, grade-separated Hauxton junction in the east, EWR are proposing to build a Great Wall across rural south Cambridgeshire.
Because the taxpayer is not given a choice on the matter, this 16-kilometre long feature is barely mentioned in the 2021 consultation document, but it does emerge from a study of their long section drawings here and here. Aside from the massive visual impact and the noise, this feature could split communities that have stood for a thousand years. It could disrupt local travel patterns for school children and adults, destroy precious farmland and cause the protected Wimpole Barbastelles to move away.
The loss in local property values is already enormous and EWRCo.’s proposed blight policy will not even scratch the surface in terms of compensation.
We understand from EWR Co. engineers, that their key design driver is to maintain the speed of the railway. It follows that it needs to be straight and level where possible. This is to serve 100mph trains all the way from Oxford to Cambridge. But the forecasted number of people per train making this trip is only o.7 perhaps rising to 1.9 on average. [18,000 trips/year, 18 x 4 trains / day see 2019 EWR Co. Technical Report §4.11]. Can someone please explain the logic of this? EWR Co. tell us 75% of the traffic will be local and that they are surprised by this. If that’s correct why on earth has it not affected the design criteria? It looks like a symptom of a boondoggle. Please build something to serve the local demand – not a bullet train on a great wall.
Cross-Section of The Great Wall
The Great Wall is of course a railway embankment and we understand that their typical cross-section is as shown in fig.1 below.
Looking at the long section diagrams linked to above we can see that the embankment height mostly in the range 5-12 metres. So we can expect the width at the base to be around 30 to 50 metres.
Our previous post on farmland impact assumed an 8m width. EWR Co are also reserving land either side of the Great Wall for construction access. We assume that the flatter land to the north of Cambridge would not need such high embankments. EWR Co. might also consider some innovation there by sinking the railway into a trench as proposed by cambedrailroad.org and shown in Fig.2
Photographer’s Impressions of The Great Wall
We asked a local photographer to create some impressions of what The Great Wall might look like in the section between Little Eversden and Haslingfield. These have been created from very recent photographs combined with railway embankments from elsewhere.
These mockups (figures 3, 5 & 7) are approximate but they do give an impression of what The Great Wall would be like. Also shown are the views from the same locations today (figures 4, 6 & 8).
The West Anglia Mainline (WAML) at Clayhithe
To get a feeling for the likely height of embankments required north of Cambridge here is a view (fig.9) of the existing WAML about 300m from the river Cam. It’s not easy to see but there is actually an embankment there. Notice also that the overhead lines are below tree height thus shielding the view from the houses behind them.
That’s not the end of the impact of this proposal by a long way, but it is enough for this post.