Peter's Waterways Blog High Speed Two This was first published in IWA West Riding's Milepost in September 2017, following a site visit on behalf of the Canal and River Trust's North East Partnership to a potential new bridge crossing of the Aire and Calder Navigation to the east of Leeds.

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Annotated HS2 map

With my North East Partnership hat on, I joined C&RT's site visit to the proposed new HS2 crossing of the Aire and Calder near the current Pipe Bridge No 7 at Stourton, which we completed on an intermittently showery afternoon in September, starting from the Thwaites Mill carpark and walking along the towing path between the Navigation and the River.

Particularly from that side of the Navigation, it is a remote area with no buildings, without really being countryside. Our particular interest in the proposed crossing is within sight of the M1 twixt Junctions 44 and 45, where it crosses the canal on a viaduct well above the minimum height for commercial traffic. The existing railway line also passes under the motorway on the opposite bank. HS2 also now plan their track level under the motorway, and the plans show the line from Leeds Station having a branch left over the Navigation into a large area to be a marshalling yard, bounded by the motorway and the junctions' slip-roads. Of all the places to build such a thing, the lack of current industrial use, and the absence of both people and any feeling of traditional countryside, must make this a good place to do it.

Pipe bridge No 7

M1 bridge

Our discussions were around the levels, clearly needing to maintain that commercial-boat minimum height, and the length of the tunnel that will be created. Clearly the current feeling of space from the Navigation will inevitably be much reduced by the new crossing, which will be lower than the current M1 crossing. The potentially oppressive tunnel would be of minimum length if the crossing was at right angles, but the plans show it between thirty and forty degrees, although the crossing itself is on a curve (see map above), and the Navigation is also wide here and also on an opposing curve. Our towpath discussions were around the flexibility of HS2 to take the crossing slightly north where is could be at right-angles, and there would be a greater distance for height adjustments, compared with the current plans. We will think some more on this and decide how best to influence HS2 thinking.

Our new line seemed to be heading straight for an existing electricity pylon, and it's hard to know if this would need to be moved in any event. If we had been scouting-out a canal restoration, this would have looked to be an expensive thing to move, but all these things are relative, and HS2 has a bigger money-tree to shake than do canal restorations.

Viewing the proposed crossing point

Dead area under bridge

Also interesting was brief discussions of the crossings, and Bridge 6, at the western end of the Thwaite Mills site is a good example of the dead areas created by having bridge supports that stand back from the edge of the canal. These seem to attract unattractive scribblings, and perhaps informal sleeping-bag residence. These undesirable elements can be eliminated at the design stage, provided that designers understand the problem that they can cause. Peter Scott @peterjohnscott