Revised, with new maps, and a new proposed alignment:
Revised with new maps: High-speed rail line Sittard – Aachen.
This proposed high-speed line (HSL) complements the reactivation of the old line Aaachen-Richterich-Simpelveld-Valkenburg-Maastricht, opened 1853 and closed 1992. The reopened line would form part of the proposed urban-regional metro Aachen (S-Bahn Aachen). The HSL would provide a fast service between the city centres: The Aachen urban region has 540 000 inhabitants, with 240 000 in Aachen itself. The city of Maastricht has 122 000 inhabitants. The HSL would also connect to other intercity services from Aachen and Maastricht.
The proposed line makes sense primarily in the context of the proposed high-speed line Hasselt – Maastricht and a high-speed service from Antwerpen to Hasselt. Together, the proposals create a new east-west high-speed route, from Antwerpen to Aachen.
The proposed line uses part of the alignment of the former Limburgsche Tramweg-Maatschappij (LTM), a steam-tram line from Maastricht to Vaals, opened in 1925. East of Gulpen, the new HSL would have a similar alignment to a possible Gulpen – Vaals – Aachen link, an urban-regional line (S-Bahn). Combined construction of both lines would be difficult: the best option is a direct HSL, together with reactivation of the old line Maastricht – Aachen, with urban-regional services via Valkenburg.
The new line would start at Maastricht Station, on the right bank of the Maas (opposite the historic city centre). The high-speed line from Hasselt would approach the station from the north, in tunnel under the Maas.
The proposed HSL from Hasselt…
Maastricht station would need redesign as a through station: at present, it is a terminal station for trains from the north. Immediately south of the station area, the rail line is constricted: the prominent Church of the Sacred Heart blocks expansion of the rail area here. Nevertheless, there is sufficient room for extra tracks, if the road in front of the church is closed. If the new platforms begin at the station building, there is also sufficient room for a grade-separated junction at the south end of the station. The road tunnel Akerstraat / Scharnerweg can probably remain in use.
South of the station, the new line to Aachen would drop into tunnel, and turn east. With the construction of the A2 motorway tunnel through Maastricht, an exit line under the Akersteenweg is no longer possible. The new line would pass under the A2 just as it enters the tunnel section, at the Europaplein junction.
The motorway tunnel entrance under construction: parallel rail line left, sports field right…
It would then pass through Heer, at first in a cut-and-cover tunnel (under the sports field). This neighborhoud consists of an old village street, surrounded by low-rise housing. Because the terrain slopes upward, the line can enter a bored tunnel about 500 m from the motorway, minimizing local demolition. With the southern alignment, in green, a bridge over the motorway might also be possible.
Alternatives for an exit line: basiskaart van Jan-Willem van Aalst, onder CC3.0 licentie…
As it leaves the built-up area of Maastricht, the line would climb 80 m toward the plateau, surfacing just east of Cadier en Keer. The 5-km tunnel would be comparable with the Tunnel de Soumagne at Liège, which has an identical function. (It carries the Liège – Aachen HSL out of the Maas/Meuse valley, to the plateau on the eastern side).
Between Cadier en Margraten, the HSL alignment would approximately parallel the N278, on the south side of the road. The main road climbs about 40 metres, in the 3 km between the two villages. Although the road through Margraten is straight, and just wide enough for a cut-and-cover tunnel, the best option seems to be an alignment south of the built-up area.
Between Margraten and Gulpen, the road falls 70 metres. The old steam tram avoided this slope, by diverging to the south, crossing the Gulp valley on a viaduct at Euverem, and entering Gulpen from the south-west. The new line will not enter Gulpen, but it would use a similar solution. It would cross a descending viaduct near the campsite at Euverem, and cross the Gulp valley. The valley floor is at about 105 m altitude. It would enter a tunnel, under the ridge between the Gulp and Geul valleys.
The line would emerge from tunnel south-west of Partij, and pass south of Partij and Wahlwiller, to rejoin the alignment of the N278. In theory, a single base tunnel is possible, from Maastricht to the Geul valley at Partij. It would be about 15 km long.
From Partij to Vaals, the alignment would be identical to that of the possible Gulpen – Vaals – Aachen link. The constraints are the same, and the best solution is to follow the N278. The line would pass just south of Nijswiller, with a tunnel under the low ridge between Wahlwiller and Nijswiller. It would rejoin the route of the N278, at its junction with the N281.
From here to Vaals, the constraints include a narrow section of the valley (Selzerbeek stream, Senserbach in German), and historical building such as the Benedictine Abbey Benedictusberg and the old centre of Lemiers. The N278 runs in a straight line, the gradient is acceptable: a rail line is possible beside the road, or in some places under the road. The road through Lemiers, which avoids the historic village core, is wide enough for a shallow tunnel.
From Lemiers, the road climbs 40 m up the flank of the valley, in less than 2 km, to the edge of Vaals. The old tram line followed an easier gradient, nearer the Selzerbeek, on the north side of Vaals. For high-speed trains the gradient into Vaals is not a problem, and the line could go in shallow tunnel through the village (thin blue line). The main street does curve in Vaals itself, which might restrict speed.
The alignment in Vaals would also be dependent on the route eastwards, to Aachen Hauptbahnhof (6 km due east). One option is to follow the main road – Vaalser Strasse, Bundesstrasse 1 – at least as far as the junction with the Amsterdammer Ring. The main road dips and curves, as it crosses the Senserbach (barely visible here), and curves again about 400 m east. However, there is enough open space is enough to allow the line to emerge from tunnel, and enter another tunnel (red dotted line), under the houses of Vaalserquartier. Another option is a long tunnel (white dashed line) under the southern half of Vaals, which is about 20-30 m higher than the main road. This tunnel would join the alignment of the freight rail line Aachen – Montzen – although this line does not go to Aachen Hauptbahnhof, and another connecting tunnel would be required
Near the western cemetery (Westfriedhof), the Vaalser Strasse crosses the Aachen – Montzen line. Here, all variants would enter a tunnel – the exact alignment and portal depends on the alignment through Vaals. The tunnel would surface close to the main station (near Weberstrasse). Because of the terrain, the built-up areas, and the crossings with roads and rail lines, a single long tunnel from Vaals might be the best option.
The exit point of the tunnel is a problem, in this densely-built urban area. Aachen Hauptbahnhof also has a restricted location, which could be improved (on the west side), by moving the northern boundary of the track area (red line), and re-aligning some of the tracks (blue lines).
The total length of the line from Maastricht to Aachen would be about 32 km. Although the line is too short for very high speeds, the section Cadier – Vaals could be aligned for 150 km/h to 180 km/h. A journey time of under 20 minutes is certainly feasible.
This proposed high-speed line (HSL) complements the proposed high-speed line Hasselt – Liège, and would share its alignment for about 9 km from Hasselt to Diepenbeek. Its purpose is to extend the proposed high-speed service Antwerpen – Hasselt. It could connect at Maastricht to the proposed Maastricht – Aachen HSL, creating a new Antwerpen – Aachen rail axis.
Hasselt (75 000 inhabitants), is only 27 km from Maastricht, in a straight line. At present there is no service between them, but a regional tram service is planned, using an old railway line. From Hasselt Belgian Line 34 runs to Liège via Tongeren. It turns south at Bilzen (‘Beverst Junction’), and the disused Line 20 continued to Maastricht, via Lanaken. The planned regional tram will run on a separate alignment to Bilzen, and then over the former Line 20 into Maastricht.
The proposed HSL is qualitatively different from the light-rail project, but it does not exclude service of intermediate stations. In fact, the HSL can avoid the old Line 20 entirely, leaving it free for a new regional rail line via Lanaken. (The HSL would however be incompatible with the planned parallel tram line through Diepenbeek, since space is limited).
For the HSL, the line out of Hasselt Station would be upgraded, with a grade-separated junction for the line from St. Truiden (Line 21). The curve at the edge of the built-up area would be improved. From there to Bilzen, Line 34 can either be upgraded as a four-track line (Ausbaustrecke), or a parallel HSL could be built directly alongside it it. Either way, all level crossings must be replaced, probably with a cut-and-cover tunnel though Diepenbeek. East of Diepenbeek, the proposed HSL to Liège would diverge, turning south toward Tongeren.
At Bilzen, the HSL would diverge from Line 34. It can not simply follow the old alignment through Munsterbilzen and Eigenbilzen, because that is too sharply curved. The section through Lanaken is also too far north.
The new line would therefore run south of Line 20, at the edge of Munsterbilzen, and probably in tunnel under Eigenbilzen. The typical sprawl around Flemish villages (lintbebouwing) makes some demolition inevitable. At Munsterbilzen, the line can be cut into a low ridge, limiting the effects.
Beverst Junction is at about 50 m elevation, and the terrain then slopes upward to the plateau above Maastricht, at about 80 m elevation. The HSL can probably run on surface on this plateau, south of Gellik, on an almost straight alignment. It must first cut through Eigenbilzen. Even if the HSL uses the old cutting through the village, some houses must be demolished for a new curve, to avoid the Albert Canal (alignment shown in blue). A tunnel just south of the village centre seems preferable: it can also take advantage of the terrain, since the village is higher than the land on the west side. A southern alignment (in white) would also avoid the castle ruins west of the village, and most of the forest at Groenendaal.
Between Briegden and Veldwezelt, the new line would cross the Albert Canal on a bridge. The west bank is about 15 m higher than the east bank here, so the line would continue on viaduct.
North of the built-up area of Maastricht (Oud-Caberg), at about 60 m elevation, the line would enter a long tunnel. This 4-km tunnel would curve slowly, to align with Maastricht Station on the opposite bank of the Maas. It would descend 40 m from the portal at Oud-Caberg, in order to cross the river – the river bank is at 45 m in Maastricht. This alignment takes it under a waste landfill, but at that depth, there should be no problem with subsidence.
The tunnel would pass under the Zuid-Willemsvaart canal, and the river Maas, emerging just north of Maastricht Station. The alignment must take account of redevelopment north of the station, and some demolition may be required. From the river to the platforms, over 1200 m is available, for the tunnel to climb to the station.
From Maastricht, trains might continue on the proposed HSL to Aachen. An alternative for that project is an express service on a re-opened Maastricht-Aachen line. The Hasselt – Maastricht line would also connect with the proposed Maas valley high-speed corridor to Venlo and Nijmegen.
The proposed high-speed line would have no intermediate stations. The new alignment Bilzen – Maastricht would be about 16 km long, and the whole line about 30 km, station to station. Journey time Hasselt – Maastricht should be about 12 minutes.
Liège is the largest city of Wallonia. With a population of 200 000, and an agglomeration of 600 000, it is large enough to justify its own regional metro, on the model of the French RER or the German S-Bahn. As the former industrial centre of Belgium, Liège also has enough railway lines. Given the short distance and the combined populations, a regional metro service to Maastricht is also justified.
The two cities lie 30 km apart on the river Maas / Meuse. The rail line between them crosses the Dutch-Belgian border at Visé. From Maastricht to Visé, the line runs through the broad floodplain, south of Visé it runs at the foot of a escarpment. The boundary between the two landscapes is at Visé Station itself.
The line in 1901, click to enlarge: base map from Uni Greifswald, with some German place names…
The line, Belgian Line 40, is underused. That is partly due to the indirect route into central Liège. Line 40 originally served a terminal station at Longdoz, on the right bank of the Meuse, opposite the historic centre of Liège. Trains could reach the main Liège-Guillemins station, but only by reversing. The present connecting line through Froidmont was built during the First World War, and is of low quality. Trains from Maastricht must cross the exit tracks of the high-speed line to Aachen, to reach Liège-Guillemins.
The Belgian section once had stations at Liège-Vennes, Cornillon, Bressoux, Jupille, Souverain-Wandre, Wandre, Château-de-Cheratte, Cheratte, Sarolay, Argenteau, Pont-d’Argenteau, and a second station at Visé for transfer to the elevated Montzen line. All but Bressoux and Visé are closed. In the Netherlands, there are intermediate stations at Maastricht-Randwyck and Eijsden: the stations at Gronsveld and Maarland are closed. The remaining stations are served by an hourly local train: a direct connection to Brussels was abandoned in 2011.
The proposal here is primarily to improve the route into central Liège, by connecting Line 40 on the east bank, to Line 34 on the west bank. The proposal can be combined with a high-speed line Maastricht – Liège, but neither is a precondition for each other.
Railways in Liège
The main station Liège Guillemins is on the old Brussels – Aachen line, and is now also served by the TGV Paris – Brussels – Aachen – Köln. The location was determined by the need to descend into the Meuse valley, not for proximity to the city centre. Line 34 to Tongeren and Hasselt diverges just north of Liège Guillemins, and runs in tunnel past the historic centre. There are two stations on that section: Liège-Jonfosse and Liège-Palais. Both are below street level, in a short cutting between tunnels. Liège-Palais Station is just behind the Palace of the Prince-Bishops and the main square of the city, and is well served by bus lines.
Both stations are served by some Intercity and InterRegio trains via Liège Guillemins, which start or finish at Herstal or Lier – in fact they are being used here as local stopping trains.
The line from Maastricht along the Maas/Meuse valley does not pass through central Liège. After passing through Bressoux, due east of the city centre, trains cross the bridge over the river and enter Liège Guillemins from the south. The proposal here is to create a line following the most logical route from Maastricht: along the valley, through central Liège, into Liège Guillemins. That can be done by connecting Line 34 to Line 40, across the Meuse, downstream from central Liège. The only practical location for a new link line is at the Ile de Monsin. The planning association UrbAgora has already proposed a similar link at Bressoux. A Monsin link is longer, but easier to build, and gives a shorter route from Maastricht.
The new 4-km link would diverge from Line 34 between Liège-Palais and Herstal. The station at Vivegnis can be re-opened at its original location (Place Vivegnis). West of that station, the line would be realigned by cutting into the hillside (at Rue des Vignes). A new alignment would diverge here, toward the river, toward the Coronmeuse roundabout. Obviously that requires demolition, but this is a former industrial area with very low-quality housing.
The new line would cross the roundabout on viaduct, and run alongside the Rue Ernest Solvay. A station here would serve the exhibition centre Halles des Foires de Liège, and offer interchange with the planned tram line, which runs roughly parallel to the river. The link line would then cross the mouth of the Albert Canal, just avoiding the existing road bridge here. It would continue along the south end of the Ile de Monsin – an artificial island, created when the Albert Canal was cut parallel to the river channel.
There might be a station on the island, close to the Monsin Barrage, but only if the area was redeveloped. The link line would then cross the Meuse and the A25 motorway, to join Line 40 at Souverain-Wandre. Most of the new link line would be on viaduct – to cross roads, to cross the river, and to pass existing bridges.
North of the new link, the regional metro would have re-opened stations at Wandre, Cheratte, and Argenteau (former Pont-d’Argenteau station). In the Netherlands, the station at Gronsveld can be re-opened, and a second station added in the south of Maastricht. The regional metro line would then have 11 intermediate stations, between Liège-Guillemins and Maastricht.
With a total length of 32 km, the average station spacing is 2700 m. That is normal for outer sections of a regional metro, such as the S-Bahn in Germany. Stations would normally be closer on a central section, but there are no suitable locations for extra stations in central Liège.
The rest of Line 40 (through Bressoux) would be used for a a right-bank regional metro line, for instance from Flémalle-Haute through Seraing and Bressoux to Visé. With a 4-track station at Liège-Palais, there is sufficient capacity for an urban-regional service on Line 34 as well, at least as far as Tongeren. With an intensive urban service from Liège Guillemins to Liège-Palais, it would no longer be necessary to extend Intercity and InterRegio trains over that section.
The purpose of a high-speed line (HSL) between Hasselt and Liège, is to extend the proposed Antwerpen – Hasselt HSL. That would create a second east-west high-speed corridor in Belgium, across the Kempen region. The corridor would also extend to Maastricht, via the proposed HSL Hasselt – Maastricht.
The original version of this proposal was a new line alongside the A13 motorway. The exit line from Liège could have been shared with a HSL Maastricht – Liège, but that would make both routes longer, without any other advantages. The new version here is a direct HSL across the agricultural Hesbaye / Haspengouw region, to join the Maastricht line east of Hasselt.
This alignment is not only shorter, it can also run through the existing Tongeren station, halfway between Hasselt and Liège. The shorter route will partly compensate for the extra stop, but journey times might be slightly longer. With two 20-km sections, a line speed of about 250 km/h is appropriate.
The existing railway
Hasselt and Liège are 38 kilometres apart in a straight line. The railway between them, Belgian Line 34, is far from straight, however: journey time is one hour. The line diverges just north of the main Liège Guillemins station, and passes the historic centre at Liège-Palais station. It then runs west, climbs out of the Meuse valley, turns east, and then follows a winding route toward Tongeren.
From the edge of Liège to Glons, the line is single-track. The Glons – Hasselt section, on the other had, is part of the Montzen freight route to Germany, which limits capacity for passenger trains. Service on Line 34 also suffers, because it crosses the language boundary in Belgium. Neither Flanders nor Wallonia are interested in the ‘cross-border’ line, preferring to develop their internal infrastructure. As always, this blog ignores politics and boundaries.
The new HSL would also diverge from the existing line, north of Liège Guillemins station. This is the main line to Brussels, which climbs out of the Meuse valley on the former inclined plane of Ans. The line out of the station is first elevated, but from the Rue Saint-Gilles it is in cutting. The line is briefly level with the terrain here, and this is a optimal site for a junction with a new tunnel. However, the proposed HSL to Maastricht would diverge first, so the tunnel portal for the Hasselt line would be further north, near the Rue Saint-Laurent. Four tracks out of Liège Guillemins are essential, so the motorway on viaduct above the line must be rerouted.
New exit line…
The tunnel portal would be at about 110 m elevation. Before climbing to the plateau above Liège, the alignment crosses the secondary valley leading to Ans, also at 110 m elevation. After about 900 m in tunnel, the new line would emerge from tunnel, cross the valley on viaduct, and dive into the valley flank again, to climb toward Rocourt. The viaduct alignment would cross three streets: demolition is inevitable, but this area is filled with decaying substandard housing anyway.
Approximate location of the viaduct…
The HSL would emerge on the plateau above Liège, at about 150 m elevation, near the Lantin prison. The longer tunnel would be about 4 km long, so the gradient is not a problem. As with all tunnels in this region, its alignment must take account of old coal mines. The line would surface near the N20 road, and it would simply follow that road across the plateau to Tongeren. The terrain is not flat, but local relief of 10-20m is not an obstacle, and this is mostly farmland. To avoid the villages, the line would probably run west of the N20 road as far as Wihogne, and then east of it.
Approaching Tongeren, the new line would drop about 50 m, crossing several low ridges at right angles. It would pass the eastern edge of Vreren, and cut through the industrial zone Overhaem. (The alignment would cross a car transporters depot, which is simply a large car park). From this last ridge, it would descend on viaduct to join the existing line into Tongeren station, avoiding the built-up area. A grade-separated junction is preferable, to allow cross-platform interchange, but the new line could have separate platforms on the western side of the station. In both cases, the station must be reconstructed.
The new route from Liège to Tongeren would be 19 km long, station to station. Of that about 17 km is new alignment, mainly on surface on the plateau.
On to Hasselt
To avoid a complex tunnel under the built-up area at Hasselt, the new line would run north from Tongeren, to join the existing line east of Diepenbeek. Just outside the station, part of the old Line 23 can be used for a new exit tunnel, under higher ground. The most direct alignment is a 5-km tunnel under Henis and Riksingen, to clear the built-up area. A longer alignment would run on surface east of Henis (parallel to the main road N730), and then turn north-west, using a shorter tunnel. Local elevation differences, up to 40 m, make some tunnels and/or viaducts unavoidable here.
The HSL alignment is not given in detail, but it would probably pass east of Sint-Huibrechts-Hern, and west of Romershoven. Between those two, it might pass east or west of Schalkhoven. North of Schalkhoven, the line would cross flat open farmland, to join the line into Diepenbeek. The new section of line would be about 14 km long.
Obviously, the line from Diepenbeek into Hasselt must be upgraded for high speed, but that can be combined with the construction of a HSL Hasselt – Maastricht. The line through Diepenbeek is dead straight: in Hasselt itself it curves around the old town centre.
The new route from Tongeren to Hasselt would be about 23 km long. Allowing for deviations to avoid subsidence and protected landscapes, the total length of the new high-speed route would be 42-44 km, station to station. Even with one stop at Tongeren, journey time would still be under 20 minutes.
New function of existing line
The section of Line 34 line through central Liège, would become part of a regional metro, including a regional metro line Maastricht – Liège. Services, comparable to those on the French RER or the German S-Bahn, would extend to Tongeren. The local service Hasselt – Tongeren would be unaffected by the new line.
Both Maastricht and Liège are built on the river Maas / Meuse, and they are only about 30 km apart. The Liège agglomeration has about 600 000 inhabitants, and the Maastricht urban region about 180 000. Language differences (Dutch and French) probably counteract proximity to some extent: the Netherlands borders directly on Wallonia here.
The railway between Maastricht and Liège was built in 1861, along the right (east) bank of the river Maas / Meuse. The river has a broad floodplain with escarpments on both sides, about 50 – 100 m above the plain.
The line in 1901, click to enlarge: base map from Uni Greifswald, with some German place names…
From Maastricht to Visé, the line is in this floodplain, and generally straight. South of Visé, the river runs alongside the eastern escarpment, leaving just enough space for motorway, road and railway. The line is sharply curved in places, at the food of a cliff. The transition between the two landscapes is at Visé Station itself, which is also the border station.
Click to enlarge: river Meuse, riverside road, motorway, and Visé station…
The line is double-track and electrified at 1500 V in the Netherlands, 3000 V in Belgium. The voltage changes at the edge of Maastricht. Belgian trains can run under reduced voltage into Maastricht station, but Dutch trains can not run at Belgian voltage. Originally, the line stayed on the right bank of the river, terminating at Longdoz Station, opposite the city centre. Trains now continue past the centre on a connecting line, and turn north again across the Meuse, into the main Liège-Guillemins station.
For a few years, the city of Maastricht promoted a “high-speed” service to Brussels. In fact it was simply a Belgian Interciy, extended from Liège Guillemins to Maastricht over the existing line. There was no high speed, and no upgrading of the infrastructure. That train now stops at Visé: there is also an hourly Maastricht – Liège regional service.
Conversion of the line to an urban-regional metro line was proposed here, as part of an urban-regional network around Liège. The line would be re-routed into the city centre, with a new 4-km line across the river at the Ile de Monsin. That is compatible with a high-speed line, but neither project is a precondition for the other.
There are two general options for a high-speed line south from Maastricht. Either the new line follows the existing right bank line to Liège, or it crosses the Maas / Meuse and the parallel Albert Canal, and enters Liège from the north. More precisely, it would enter Liège-Guillemins from the north-west, sharing the approach tracks through Ans with the old main line from Brussels, and the high-speed line Brussels – Aachen. That requires a long tunnel from the river valley to the junction with the approach line, much of it under the built-up area of Liège.
In both variants, the existing line south of Maastricht would be doubled to four tracks, and upgraded for high speeds. Inside Maastricht no high speeds are possible: there is a curve just south of the station, and another at Randwyck, 1400 m further. Just before Randwyck station, the proposed HSL Maastricht – Aachen would diverge, requiring reconstruction of the curve, and probably relocation of the station.
The remaining line to Visé consists of two straight sections, with a curve at Eijsden. There is enough room for four tracks, and most of the line is in open fields. At Eijsden, the line cuts the village in half, and a cut-and-cover tunnel is preferable. That can be combined with a new curve: the station itself would remain on the surface.
The options for crossing the Meuse and Albert Canal are limited. On the west bank south of Maastricht there are quarries, cement plants, a preserved fortress (Fort d’Ében-Émael), and a nature reserve on the escarpment (Thier de Lanaye). Closer to Liège, both banks are urbanised. The most open section of the valley floor is south of Visé, and the tunnel on the west bank would then start near Oupeye. To cross the valley at the best angle, the new line would need to curve south-west, requiring another tunnel under Visé. That might be connected to a bypass of Eijsden (brown on the map).
The distance would be about 35 km, and journey time should be reduced to 15 minutes or less. The exact alignment can only be determined by detailed studies. An earlier proposal here, an alignment along the A13 / E313 motorway, offers no advantages.
The alignment through Oupeye is largely determined by the location of Liège Guillemins station, and the approach tracks through Ans. The line, the oldest railway in Belgium, was built well south of the historic city centre, because following the valley at Ans avoided a steep drop into the Meuse valley. In fact, the line here was originally an inclined plane. The inconvenient location of the main station is the result.
The tunnel alignment shown is indicative only. It crosses a valley, with the Ans line on the southern flank, and if this was not an urbanised area, a bridge would be more logical. However, the valley is not too deep for a tunnel on the approximate alignment shown. (The tunnel would be close to a similar exit tunnel for the proposed HSL Liège – Hasselt, but to avoid an underground junction both should have separate portals and alignments).
A new high-speed line along the Maas / Meuse valley, parallel to the existing line, would also require new tunnels. South of Visé, the line is too curved for high speeds, and, the line is often squeezed between the old main road and the motorway. The only option is a flank tunnel, or a series of flank tunnels, starting at Visé itself. The main issue is the last section into Liège Guillemins, to replace the inconvenient approach line.
The line through Visé Station is curved and for that reason alone unsuitable. Because the town is built on higher ground, a tunnel can pass under the centre, shortening the route slightly. In principle the tunnel would be level, at about 55 m elevation, but it might dip to clear buildings near the portals. It would rejoin the line near Richelle, so it would be about 4 km long.
A second flank tunnel, about 9 km long, would start near Richelle and emerge from the escarpment at Jupille, just north of the Jupiler brewery. Again the line would be ‘level’ in principle: more accurately, it would match the gradient of the river. Construction would be simplified by access ‘from the side’, since the tunnel will be close to the road. As with all tunnels in this region, construction must take account of former coal mining – shafts, galleries, and subsidence.
A single flank tunnel of about 14 km is also possible, but even in that case a junction with the old line at Richelle might be desirable. (At that point, the tunnel would be just behind the escarpment).
From Jupille to the railway yard at Bressoux, the line is straight. After that, it is double-track but curved: no alternative alignment is available since it cuts through residential areas. The HSL would require another tunnel, into the city centre.
One possibility is that the HSL would emerge from tunnel north of Jupille, and run parallel to the proposed Monsin link line. This link is intended to connect Line 40 to Line 34 across the Meuse valley, to create a regional metro line from Maastricht into central Liège.
On the opposite bank, the HSL would dive into the hillside in tunnel, and turn to run parallel to Line 34. This last section would not allow high speeds, but it is only 3 km long. It would run under the Parc de la Citadelle, and terminate at an underground station, alongside Liège-Palais Sation. This would allow easy transfer to a regional metro, at a station just north of the historic city centre..
Combined with the flank tunnels, this would shorten the route from Maatsricht to central Liége to just under 30 km. The last tunnel can be extended to Liége-Guillemins station, for interchange with the Brussels – Aachen high-speed route, and with Intercity services. The junction would be relatively close to the station, where the A602 motorway was built on pillars above the railway line, making it impossible to modify. Relocation of the motorway seems a precondition for this junction – and for doubling of the line, which carries all traffic west from Liège.
This is only one of several possible tunnel alignments. The shortest route is simply a tunnel under Outremeuse, from Bressoux to the centre, but there is no good site for a station, so it would be entirely underground. The station would have deep platforms, since the line must pass under the river, and the city centre is on higher ground. This route is also more difficult to connect to Liége-Guillemins station. The possible tunnel alignments into the city centre are not considered further here.