Thursday, 10 July 2014

East of Lymm

The earlier articles can be found here HS2 Phase 2 Liverpool & From Ditton to Lime Street.

From HS2 to Warrington

In planning to use the remaining track of Warrington & Stockport line to provide access to for Liverpool. It is important to understand that this part of the line would not be capable of the high speeds on the mainline nor could it have the same wide cross section. It is not intended that it should be a captive line spur of HS2 but that it should provide passage for HS2s GC gauge trains at reasonable speeds and with an unobstructed run.
This does not mean that other services could not use the line, but that they would have to totally subordinate to the HS2/HS3 trains. The route could provide an opportunity to provide a link between Warrington and Altrincham and Manchester Metro Link. The line could also carry Train/Trams from Widnes to the Warrington BQ providing a feeder service from both sides, potentially with some intermediate tram stops.
There are several obstacles other than the lack of GC gauge to overcome if parts of the Warrington & Stockport line is to be used as part of the spur from HS2 to Liverpool.
In several places there are level crossings which would need to be replaced with bridges, there are several existent bridges where the clearance may need to be increased. The state of the tunnel under the M6 is unknown, all that can be said it that up until 1988 trains used a tunnel to pass under the Motorway, what has happened since then is unclear.
South of Lymm
One thing that has happened however is that a number of the settlements have grown along the track and may even have encroached on it in places, and while these may not present a physical obstacle to the route, they will most certainly need to be addressed if any of the residents are to be in any way happy. It is unlikely that the residents will just accept that after 30 years trains are to be reintroduced and that those trains will be travelling faster than before and therefore making more noise.
There is also the matter of the Trans Pennine way which uses the track bed as part of its route.

Existing route

Of the 2 miles between HS2 and the M6, the 0.8 miles north of Rushgreen.
And the 0.9 miles between Lymm & Statham need to have the maximum mitigation. The 4.2 miles to Warrington, from the M6, has a greater uninhabited area around it and with the trains either slowing for Warrington station or accelerating from the reduced speed should significantly reduce noise. However, some mitigation may be needed and be possible.

Trains & Pantographs

The Japanese have done considerable research into lowering the sound produced by high speed trains two of these can be founhere & here.
For the pantograph one modification suggested is piecing the collector to allow air through the collector, the complex airflow that this produces introduces destructive interference reducing the over sound levels.
One of the more significant sources of noise is the wheels. The metal wheels against the metal track induces vibration in both. The Japanese are starting to use full enclosed bogies to reduce the noise level at track side.
A further possibility might be to use an active suppression system in which electromagnets, controlled by the computer are used to induce destructive interference. I can find no reference to experiments being done in this area, but it would seem to be a technique with possibilities. The system would need to contain a sensor capable of quickly determining the vibration pattern in the wheel, allowing the computer to control the magnets to cancel this out.

Tracks

Various mass damping system have been suggested for reducing the noise from train lines 2 of these are described here or here. It may be possible to further enhance this using an active system similar to the one suggested for damping wheels.

Track bed

Various reports have been produced by using various system for reducing the transmission of sound via the track bed. The Benefits and Limitations of Floating Slab Track for ControllingGroundborne Noise and Vibration/
One system if made by Tiflex, see http://www.tiflex.co.uk/track_home/fst/fst.html

Walls, Tunnel and earth banks

One the primary methods of reducing noise pollution from trains is via the use of sound absorbing walls. Where shielding is needed on only 1 side this would be ideal. However, in other areas where shielding is needed, it may make more sense to enclose the entire track in a prefabricated box tunnel. This would also be useful in isolating the track from external interference, providing protection for both the track and the general public.
Where a tunnel is used, the entire structure can be covered by earthwork providing further sound insulation as well as removing the concrete from view. It may also allow the height of the structure to be lower, as no addition fencing will be needed.
Using Ballast free track it would be possible to integrate the base of the track into the floor of the box.

Replacing Level Crossings

There are 7 level crossings on the proposed route, none of them are major roads at a rough estimate it may be possible to replace them at between £10-£15 million. This is based upon several articles citing network rail quotes.

Route description

Proposed HS2 route.
  1. Bridge over River Bolin. See map here.
    • The track bed here is bounded on either side by fields.
  2. Level Crossing at the site of Heatley & Warburton station. See map here.
    • The old station buildings appear to intact and in use as residential housing, there is a small business unit to the south of the line. Land is available to the west to allow a temporary relief road while a bridge is constructed over the track bed. The road is the B5169
    • After a short distance the track is bounded to the south by Farcroft Close, on the south side of the road are houses. This situation or similar continues for about 1300 meters, a distance which includes several level crossings. There is a 200 meter stretch where the line is also bounded to the north.
  3. Level Crossing at Birch Brook road & Chaise Meadow, Lymm Cheshire. See map here.
    • These two crossing are close together and is seems that there is enough space to divert traffic between the 2 using the track bed and some adjoining roads. This is particularly important in the case of Chaise Meadow is it provided the only access to a housing estate south of the line. Birch Brook road is the A6144 and while the diversion via Chaise Meadow could be used, there a several other alternative routes. Installing 1 bridge and then the other would create the minimum inconvenience.
  4. Level Crossing at Reddish Crescent. Lymm, Cheshire. See map here.
    • This level crossing is over a minor road and both, land for a re-routing and alternate routes are available. This crossing is also at the western end of the buildings in RushGreen.
  5. Underpass at Reddish Lane, Lymm, Cheshire. See map here.
    • This seems to be a farm underpass that may provide access to a series of allotments. It may be usable to provide relief for when the following level crossing is bridged.
  6. Level Crossing Lymmhay Lane, Lymm, Cheshire. See map here.
    • This seems to be a farm level crossing pass that may provide access to a series of allotments. If it were to be bridged the precede underpass might provide sufficient alternative. It may be possible that improvements in the underpass could render this crossing redundant or perhaps reduce it to a pedestrian bridge. From this point there is housing to the south of the route for the next 1400m.
  7. Level Crossing at the site of Lymm Station. Whitbarrow Road, Lymm, Cheshire. See map here.
    • From this point on, the route has housing on both sides. Whilst bridging at this point an alternative route exists via the following Barsbank Lane crossing. Here the old station building still exists and seem to be used as private residences.
  8. Level Crossing Barsbank Lane, Lymm, Cheshire. See map here.
    • This level crossing has, close to it, buildings that were in existence when the line was in use. There appears to be no encroachment and an alternative route via the preceding level crossing exists for use during construction.
  9. Foot Bridge intact. See map here.
    • Clearances would need to be checked. This marks the end of the buildings, on both sides of the route.
  10. Bridge at Camsley Ln(A56), Lymm, Cheshire, See map here.
    • This a modern bridge which is in good condition. The clearances may need to be increased.
  11. M6 See map here.
    • The M6 was built before the closure of the line and a tunnel was provided, the state and height of that tunnel are unknown, though presumably is still there, though it may have been in-filled, in which case it will need to be emptied and the clearance increased.
  12. Bridge over. See map here.
    • This appears to be a farm track bridge which is still in use at this point the line is in a slight cutting.
  13. Underpass. See map here.
    • This appears to be an underpass associated with a farm.
  14. Bridge over lines at Deans Lane. See map here.
    • The bridge carries a small possibly B class road.
    • Around this area are several buildings to the north of the line. This continues for 200 meters, though at point there is a road between the line and the houses. There may be a need for pedestrian bridge here to provide access to the Bridgewater canal.
  15. Bridge over. See map here.
    • Seems to be a small farm track.
  16. Bridge over Stockport Road(A56). See map here.
    • This is a fairly major modern bridge. From this point on towards the west the amount of land on either side of the track increases.
  17. Underpass at Bradshaw Lane See map here.
  18. Viaduct over MSC. See Map here.
    •  There are tracks across the bridge, but they are unusable. Apparently it was the repairs needed to this viaduct which forced the final closure of the line, in 1986. It conditional is not likely to have improved in 30 years.
  19. Underpass taking Knustford Road(A50). See map here.
  20. Underpass taking Grammar School Road. See map here.
  21. Site of Latchford station, now Cantilever Gardens See map here.
  22. Underpass taking Wash Lane. See map here.
  23. Pedestrian underpass. See map here.
  24. Pedestrian underpass. See map here.
    • Start of usable track head end shunt. Housing to the north of the line.
  25. A bridge carries Wilderspool Causeway over. See map here.
  26. Viaduct over Mersey. See Map here.
  27. Site of Warrington Arpley station.
  28. A bridge carries Slutchers Lane over. See map here.
  29. Passes under Warrington Bank Quay station and WCML. See map here.

South of Lymm Route

Most of these problems occur to the east of the M6(Item 11) in Lymm, one solution would be to build a new alignment of 4 to 5 miles stretching from HS2 and heading Northwest intercepting the Warrington and Altrincham line alignment near where it pass under the M6.
It is unlikely that the interception can happen east of the M6 due to the tight curves this would require, this would necessitate building an M6 crossing. It may also be needed to start the spur south of the M56 necessitating another motorway crossing. In addition the Bridgewater canal would have to be crossed. This would remove the need to build 7 crossings of level crossings and the additional sound proofing but it would be far more expensive.

Trans Pennine trail

If a boxed and covered tunnel is used, then it would be possible to use the top of the tunnel as a route for the Trans Pennine trail. However, at the site of Thelwall station the Trans Pennine trail is very close to the Bridgewater canal, the canal follows a more winding route but eventually approaches very close to the rail line at Altrincham. The track from Bradshaw Lane east may be wide enough to fit both the line and the path. However, after passing under the A56 Stockport road some land may need to be acquired to provide an alternate track.

No comments:

Post a Comment