Project record

Fehmarnbelt Fixed Link Immersed Tunnel

Aerial view of the two IVY immersion pontoons positioned in the Fehmarnbelt work area during the second-element operation in June 2026

Femern A/S

Femern A/S and Femern Link Contractors have moved the 18-kilometre Denmark-Germany fixed link into a three-element repeat sequence. The third standard element left Rødbyhavn on 30 July, was immersed on 31 July and connected on 1 August 2026. Each unit is 217 metres long and more than 73,500 tonnes. Three of 89 elements are now in place, but the owner has not published a new installed-length total, accepted protection quantity, series production rate or replacement opening date.

Project signal

Construction in Denmark / Germany

Current status Third tunnel element immersed and connected on 1 August 2026; protection, serial immersion, systems integration, and a two-stage road-then-rail opening remain active Source confidence Confirmed

Location

Denmark / Germany / Europe

Segment

Immersed tunnels and marine crossings

Status

Third tunnel element immersed and connected on 1 August 2026; protection, serial immersion, systems integration, and a two-stage road-then-rail opening remain active / Confirmed

Last checked

2 August 2026

Coverage

Related sectors

Immersed tunnels and marine crossings is the primary work classification. Related sectors connect this record to adjacent marine delivery and market coverage.

Subject index

Related subjects

These subject pages bring together related projects, technical articles, reports, and evidence methods.

Project anatomy

Contract scope and delivery roles

Client / authority
Femern A/S
Delivery parties
Femern Link Contractors (FLC), Fehmarn Belt Contractors (FBC), Femern SICE Cobra (FSC), Elecnor
Contract route
Femern A/S is the Danish state-owned client under Sund & Bælt. FBC, a Boskalis-Van Oord consortium, is responsible for marine dredging, work harbours, reclamation, and preparatory portal works. FLC's contracts for the element factory, immersed tunnel, portals, and ramps became effective on 1 January 2021. FSC holds the electro-mechanical systems package, while Elecnor is delivering the transformer station. The project is financed through Danish state-guaranteed loans repaid by road tolls and railway charges, with EU support. A replacement overall programme and final cost outcome have not been published after the immersion delay.
Execution window
The Danish site works began in 2020 and the principal tunnel contracts became effective in 2021. The 18-kilometre trench was declared fully excavated in April 2024. The first standard element was immersed and connected in May 2026, the second in June and the third on 1 August after a tow that began on 30 July. Sund & Bælt has stated that the former 2029 opening is no longer realistic and is developing a staged opening in which road traffic starts first and railway service follows after the German land connections are ready. Replacement opening dates have not been set.
Works package
The crossing comprises approximately 18 kilometres of immersed tunnel carrying a four-lane motorway and two electrified railway tracks in separate tubes, plus a service tube. The marine system uses 79 standard elements, each 217 metres long and about 73,500 tonnes, and 10 shorter special elements with lower-level technical spaces. The completed trench averages about 12 metres deep and 100 metres wide and required excavation of about 15 million cubic metres. Elements are serially cast at Rødbyhavn, floated through purpose-built basins and harbour, towed roughly two kilometres to the trench, lowered onto a prepared gravel bed, joined, secured with gravel and sand, and covered with stone.
Marine interfaces
Each immersion joins industrial element production to ballast control, harbour release, tug coordination, the IVY immersion pontoons, wire-guided positioning, survey and laser confirmation, seabed bedding, water-pressure-assisted joint closure, side backfill, and stone cover. Standard and special elements have different handling requirements. The sequence must also respect weather and metocean windows, navigation safety, German plan-approval limits on underwater noise and the location and timing of work, portal readiness, and the handover boundary from civil works to ventilation, lighting, safety, power, road, and railway systems.
Commercial evidence boundary
The third operation adds evidence of repeatability, but it does not establish mature series productivity. The owner says each immersion gives FLC more experience and that preparations for the next element are continuing. It has also stated that the specialized immersion-vessel delay put Danish construction about two years behind the former programme. A road-first opening reduces final-stage interface complexity but does not close the German railway, systems, safety, or commissioning obligations. Cost and repayment effects should remain owner-controlled until a revised schedule and financial frame are published.

Project timeline

Material developments

Dated events that changed scope, counterparties, delivery, commissioning or operating status.

Open this project in the Change Log

Third standard element immersed and connected

FLC completed a third tow, immersion and connection sequence, after which stone and gravel protection began. The owner confirms three of 89 elements in place but does not publish a new installed-length total, accepted protection quantity, mature cycle time or overall completion percentage.

Source

Second standard element immersed and connected

The owner record demonstrates an early repeat of the 73,500-tonne tow, positioning, immersion, and joint sequence and reports more than 500 metres installed; it does not establish mature series cadence, completed protection, or overall tunnel completion.

Source

Owner adopted separate road-first and rail-later opening paths

The decision changes the operating-release sequence and makes German railway landworks a separate service dependency, while replacement road and rail opening dates, final systems acceptance, and cost effects remain unpublished.

Source

First standard element immersed and joined to the Danish portal

The first-of-kind operation proves the initial 217-metre element could be towed, lowered, positioned, laser-confirmed, and hydraulically connected, without proving repeat productivity or acceptance of the remaining 88 elements and systems.

Source

Owner withdrew the former 2029 opening baseline

The preparation update establishes that the immersion-vessel delay made a 2029 opening unrealistic and that a new overall schedule would follow early immersion experience; it does not publish replacement dates or a revised final cost.

Source

Eighteen-kilometre tunnel trench excavation completed

The owner record closes the main dredging phase at about 15 million cubic metres and identifies FBC's Boskalis-Van Oord delivery role, while bedding, immersion, backfill, protection, portals, systems, and opening remain separate packages and gates.

Source

Evidence gap

What remains unverified

Outstanding evidence

  • Fourth and subsequent standard-element tow, immersion, joint, and protection cadence
  • First special-element production and immersion learning
  • Gravel-bed acceptance, survey evidence, side backfill, and stone cover
  • German-water environmental and underwater-noise work windows
  • Portal, road, railway, power, ventilation, lighting, and safety-system interfaces
  • Published road-opening programme and later railway-opening programme
  • Owner-approved cost, repayment, and schedule revisions

Related records 2

Reporting status

Construction, confirmed confidence

Last checked 2 August 2026 across 11 cited sources. The dated timeline above carries the project events.

Last checked 2 August 2026 Cited sources 11

Sources and related records

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Source collections

Project sources 11