The Fehmarn Belt Fixed Link Land Connections

The Fehmarn Belt Fixed Link Land Connections

New Storstrømmen and Fehmarn Sound Links

Two new links are planned. One about 1 kilometre (0.6 mi) long at the Fehmarn Sound and one slightly more than 3 kilometres (2 mi) long at Storstrømmen. According to the 2008 Danish–German treaty, the bridges did not have to be replaced, and the double-track railway construction in Germany may be delayed by up to seven years. Because of its bad condition, a replacement of the Storstrøm Bridge has been contracted and is slated for completion in 2026. The Schleswig-Holstein State Government announced in 2013 it envisioned the construction of a new Fehmarn Sound link or an upgrade of the current Fehmarn Sound Bridge, since it considered the current bridge – with two lanes for road traffic and one track for rail traffic – to be a bottleneck for the German hinterland connection. On 3 March 2020, the German Federal Ministry of Transport, the State of Schleswig-Holstein and Deutsche Bahn announced that a new 1.7 km long immersed Fehmarn Sound Tunnel (German: Fehmarnsundtunnel) with four road lanes and two rail tracks, costing approximately 714 million euros, is planned to be built by 2028, while the current bridge will be preserved for pedestrians, cyclists and slow road traffic.

Railway axis Fehmarn Belt

The Fehmarn Belt tunnel's railway is the central section of the 'Railway axis Fehmarn Belt', which is Priority Project 20 of the Trans-European Transport Network (TEN-T) that seeks to establish a high-speed rail line Copenhagen–Hamburg. In the north, it connects to the Øresund Bridge/Drogden Tunnel (Priority Project 11) and the Nordic Triangle railway/road axis (Priority Project 12), and in the south to Bremen and Hanover. The full line currently under construction consists of several new railways to be built and old railways to be upgraded, to achieve at least a maximum speed of 200 km/h (125 mph) on all sections:

Copenhagen–Ringsted Line, opened on 31 May 2019, since 2023 operating at 200 km/h (125 mph).
Sydbanen (Ringsted–Rødbyhavn), new tracks to be laid by 2021, to be electrified to reach 200 km/h (125 mph) by 2024.
Fehmarn Belt Tunnel (Rødbyhavn–Puttgarden), 200 km/h (125 mph), to be completed in 2028. (since revised)
Puttgarden–Lübeck railway, to be electrified and upgraded to reach 200 km/h (125 mph) up from the current 100–160 km/h (60–100 mph). The new Fehmarn Sound Tunnel (to be completed in 2028) is part of this section.
Lübeck–Hamburg railway, to be upgraded to reach 200 km/h (125 mph).

Tunnel Characteristics

Underwater tunnels are either bored or immersed: tunnel boring is common for deepwater tunnels longer than 4 or 5 kilometres (3.1 mi), while immersion is commonly used for tunnels which cross relatively shallow waters. Immersion involves dredging a trench across the seafloor, laying a foundation bed of sand or gravel, and then lowering precast concrete tunnel sections into the excavation and covering it with a protective layer of backfill several metres thick.

An immersed tunnel is planned for the Fehmarn Belt. At 17.6 km (10.9 mi), it will be the longest ever constructed, surpassing the current largest immersed tube tunnel, which spans 6.75 km (4.19 mi) across the Pearl River Estuary in China as part of the Hong Kong–Zhuhai–Macau Bridge. On 30 November 2010, Denmark's Femern A/S project manager announced it had selected immersed tunnel design submitted by the Ramboll, Arup, and TEC consortium. According to the senior project managers, as well as being the world's longest immersed tunnel, it will be the "world's longest combined road and rail tunnel, the world's longest under water tunnel for road, the deepest immersed tunnel with road and rail traffic, and the second deepest concrete immersed tunnel." The size of the project is about five times the tunnel part of the Øresund Link between Denmark and Sweden, currently the "longest immersed concrete tunnel."

The deepest section of the Fehmarn Belt Trench is 35 metres (115 ft) and the tunnel sections will be about 10 metres (33 ft) high, thus, the dredging barges will need to be capable of reaching depths of over 45 metres (148 ft). Dredging will produce a trench some 40–50 metres (130–160 ft) wide and 12–15 metres (39–49 ft) deep. These parameters give a total of some 20,000,000 cubic metres (710,000,000 cu ft) of soil to be dredged. Conventional dredging equipment can only reach to a depth of about 25 metres (82 ft). To excavate the middle portion of the Fehmarn trench – deeper than 25 metres (82 ft) below the water's surface – will likely require grab dredgers and trailing suction hopper dredgers.

The proposed tunnel would be 17.6 kilometres (10.9 mi) long, 40 metres (130 ft) deep below the surface of the sea and would carry a double-track railway. Arguments brought forward in favour of a tunnel include its starkly reduced environmental impact, its independence from weather conditions, as crosswinds can have considerable impact on trucks and trailers, especially on a north–south bridge. A bored tunnel was deemed too expensive.

The precast concrete tunnel sections will have a rectangular cross-section that is about 40 metres (130 ft) wide and 10 metres (33 ft) high, containing four separate passageways (two for cars and two for trains), plus a small service passageway: There will be separate northbound and southbound tubes for vehicles, each 11 metres (36 ft) wide, each with two travel lanes and a breakdown lane, while the northbound and southbound passageways for trains will be 6 metres (20 ft) wide each and about 10 metres (33 ft) high, the service passageway will be 3 metres (9.8 ft) wide, the standoff space between each "tube" will vary, but the overall width will be 41.2 metres (135 ft). The single-level, sectional arrangement of the two road and rail tubes side-by-side – with the road west and the railway east – coincide with the arrangement of the existing road and rail infrastructure, and requires no weaving to connect.

Fehmarn Belt Fixed Link Overview

Fehmarn Belt Fixed Link Official Name: Femernbælt Link
Fehmarn Belt Fixed Link Coordinates: 54°34′33″N 11°18′20″E
Fehmarn Belt Fixed Link Status: Under construction
Fehmarn Belt Fixed Link Crosses: Fehmarn Belt
Fehmarn Belt Fixed Link Work Begun: 1 January 2021
Fehmarn Belt Fixed Link Opens: mid-2029
Fehmarn Belt Fixed Link Owner: Femern A/S
Fehmarn Belt Fixed Link Traffic: rail and road
Fehmarn Belt Fixed Link Toll: yes
Fehmarn Belt Fixed Link Technical Length: 17.6 km (10.9 mi)
Fehmarn Belt Fixed Link No. of Tracks: 2
Fehmarn Belt Fixed Link No. of Lanes: 4
Fehmarn Belt Fixed Link Electrified: yes
Fehmarn Belt Fixed Link Operating Speed: 200 km/h (125 mph)