Shani Wallis, Editor

Threatened collapse of contract has been averted and TBM tunnelling under the Danube has resumed for the new Metro Line 4 project in Budapest. A truce was reached last week between design-build tunnel contractor Bamco and project owner BKV and its project management company DBR Metro after Bamco held the project to randsom and brought the contract to the brink of termination about four weeks ago.

Vertical alignment of the 10.5km Metro Line4

The standoff was reached in April (2009) when Bamco brought its two EPB TBMs to a standstill on the west side of the Danube saying it would not continue without immediate settlement of €115 million in claims and presentation of proof that Budapest has insufficient funding in place to complete the project. BKV stood its ground and gave Bamco two weeks to resume tunnelling. On Friday May 15, an agreement was struck, termination was avoided, and Bamco has since resumed work. Earlier in the week, John Larke, Contracts Manager for DBR, confirmed to TunnelTalk that "a series of high level talks between all stakeholders had found agreement to enable work previously suspended, to resume with the utmost dispatch".

Reported issues of disagreement however run deep. According to local newspapers, the Bamco tunnelling consortium, comprising Vinci of France, Strabag of Austria and local partner Hidepior Zrt, alleges interference in the design-build contract by BKV/DBR since it was awarded in 2006. It has lodged claims worth €115 million for increases in costs as a result of various issues. The consortium has also expressed doubts that the two government stakeholders in the project (21% by Budapest City Council and 79% by the national government) can fund the project to completion, after seeing Hungary’s credit rating in the global economic slowdown, downgraded by various rating agencies. For its part BKV/DBR rejects the €115 million in claims as unrealistic set against a design-build contract value of €211.7 million and states that Bamco has submitted more claims than all the other contractors on the project combined.

A Bamco TBM breakthrough

For Bamco, the climb-down commits the JV partners to completing the running tunnels under the Danube and on to their final breakthroughs at the Keleti main railway station. Had the contract been terminated the DBR said it would either rebid continuation of the contract, causing a hiatus in progress of about a year, or finish the project itself. According to contract terms, all equipment would remain on site and DBR Project Director Gusztáv Klados stated that the organization has the necessary experience and expertise to progress the contract to its conclusion.

Fig 1. Metro Line 4 alignment under the Danube

Construction of Budapest’s Metro Line 4 started in 2006 when the State and City Governments approved funding for the US$1.58 billion Phase 1 section. Following concept design by Hungarian firms Fomterv and Uvaterv and in association with Mott MacDonald of the UK, Phase 1 was divided into 11 contracts. The first and largest of these being awarded to Bamco. The €211.7 million design-build contract covers construction of the 7.3km of running tunnels from the Kelenföldi station on the Buda side of the city, under the River Danube to the Keleti main railway station on the Pest side. Bamco is also excavating the Gellért tér station. The other nine underground Phase 1 stations are awarded as separate open-cut and top-down box excavation contracts. Phase 2 of the line from Keleti to Bosnyak tér or square, includes a further 3.2km of twin running tunnels and four extra stations (Fig 1).

To complete the 7.3km of bored tunnels for Phase 1, the consortium procured two 6.05m diameter Herrenknecht EPBMs. These were launched at the Kelenföldi station on the Buda side of the Danube and will end at the Keleti station on the Pest side.

Running tunnel built to date

Construction of the Szent Gellért station by Bamco is a combination of open cut work for the station ticket hall and mined NATM excavation for the station platforms. It also includes a large NATM rail crossover chamber that is being enlarged from the bored running tunnels.

Fövám tér station, the first on Pest side of the Danube is a complex construction being completed by a separate station contract. It is one of the deepest stations, at 46m deep, and requires ground-freezing support of NATM excavation of the platform tunnels that extend out under the river.

All works on the line are under construction and have progressed some 40-45% towards an opening date for Phase 1 of the line in 2011. The final Phase 2 is due to open in 2013.

The standoff by Bamco came to a head when the second of the two TBMs had broken through into the Szent Gellért station in March. The machines had been either pulled through or had mined through the zones of the previous stations to avoid holding up their progress by other contractors. The machines could remain in Szent Gellért tér station works during the shutdown.

The core of Bamco’s claims are said to arise from three major delays incurred to date. These started with delayed acquisition of a property at the Buda working site, that delayed launch of the TBMs; technical difficulties claimed by Bamco a few months later; and structural damage to a building at the Budapest University of Technology that slowed passage of the second TBM after the first had passed through.

Eventual resolution of the contractual impasse was said to have been facilitated by a change in management at Bamco with administration of the contract passing from Vinci to Strabag. The first of the two TBMs started its drive under the Danube on Tuesday 19 May and is expected to breakthrough into the Fövám tér station on the other side within about five weeks. With new management at Bamco in place, DBR Metro Project Director Klados said he anticipated no further contractual holdups en-route to final breakthrough for the Phase 1 running tunnels at the Keleti station in 2010.

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