The Eurasia Tunnel () is a road tunnel in
Istanbul
Istanbul is the List of largest cities and towns in Turkey, largest city in Turkey, constituting the country's economic, cultural, and historical heart. With Demographics of Istanbul, a population over , it is home to 18% of the Demographics ...
,
Turkey
Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...
, crossing underneath the
Bosphorus Strait. The tunnel was officially opened on 20 December 2016
and opened to traffic on 22 December 2016.
The
double-deck tunnel connects
Kumkapı on the European part and
Koşuyolu, Kadıköy, on the Anatolian part of Istanbul with a route including the tunnel approach roads.
It crosses the Bosphorus beneath the seabed at a maximum depth of −.
It is about south of the undersea railway tunnel
Marmaray, which was opened on 29 October 2013.
The journey between the two continents takes about 5 minutes.
Toll is collected in both directions. As of 16 August 2024, daytime tariff is
₺156 ($4.50
USD
The United States dollar (symbol: $; currency code: USD) is the official currency of the United States and several other countries. The Coinage Act of 1792 introduced the U.S. dollar at par with the Spanish silver dollar, divided it int ...
) for cars, ₺234 ($6.74
USD
The United States dollar (symbol: $; currency code: USD) is the official currency of the United States and several other countries. The Coinage Act of 1792 introduced the U.S. dollar at par with the Spanish silver dollar, divided it int ...
) for minibuses and
₺60.80 ($1.75
USD
The United States dollar (symbol: $; currency code: USD) is the official currency of the United States and several other countries. The Coinage Act of 1792 introduced the U.S. dollar at par with the Spanish silver dollar, divided it int ...
) for motorcycles. A 50% discount is applied during nighttime hours.
Background
In 1891, French railway engineer
Simon Préault presented a preliminary project for an underwater tubular bridge "patented by the Ottoman imperial government", consisting of a submerged bridge supporting a tube where steam trains would run.
The conceptual background of Eurasia Tunnel reaches back to the findings of the 1997 Transportation Master Plan undertaken by
Istanbul University
Istanbul University, also known as University of Istanbul (), is a Public university, public research university located in Istanbul, Turkey. Founded by Mehmed II on May 30, 1453, a day after Fall of Constantinople, the conquest of Constantinop ...
on behalf of
Istanbul Metropolitan Municipality
The Istanbul Metropolitan Municipality (, İBB) is the government agency in charge of the municipal affairs of the Istanbul Province. It is one of the 30 metropolitan municipalities in Turkey.
History
The Istanbul Metropolitan Municipality ...
. Based on this plan, a pre-feasibility study had been conducted in 2003 for a new Bosphorus crossing. According to the results of this study, a road tunnel was recommended as the solution that offered the highest degree of feasibility.
The
Ministry of Transportation, Maritime and Communication of Turkey commissioned a feasibility study by Nippon Koei Co. Ltd. in 2005 to assess route alternatives for a new tunnel crossing. Based on environmental and social criteria, cost and risk factors, the study concluded by supporting the initially proposed route as the preferred option.
The
three current bridges across the Bosphorus were taken into consideration in selecting the tunnel's location, which was put farther south to better balance the distribution of traffic between the crossings. Other selection criteria included the route's lower investment cost due to a shorter tunnel length and the availability of sufficient space for construction sites and operational buildings (toll plaza, administrative units). High level assessments based on corridor alternatives that are comprehensively defined in the feasibility study also support the selection of the proposed route in terms of environmental and social costs and risk factors.
Investors
Avrasya Tüneli İşletme İnşaat ve Yatırım A.Ş. (ATAŞ) was founded on 26 October 2009 by the partnership of
Yapı Merkezi from Turkey and
SK E&C from South Korea.
The
build–operate–transfer
Build–operate–transfer (BOT) or build–own–operate–transfer (BOOT) is a form of project delivery method, usually for large-scale infrastructure projects, wherein a private entity receives a concession (contract), concession from the public ...
model adopted at the Eurasia Tunnel, has brought together the private investment dynamism and their project experience, and the support of international financial institutions.
The concession lasts 29 years.
Partnership contract includes guaranteed minimum revenue and profit sharing for parts exceeding guaranteed revenue.
The
European Bank for Reconstruction and Development
The European Bank for Reconstruction and Development, shortened to EBRD ( French: ''Banque européenne pour la reconstruction et le développement'' or ''BERD''), is an international financial institution founded in 1991 in Paris. As a multilat ...
(EBRD) is supplying a finance package worth US$150 million. Other components of the US$1.245 billion financing package include a $350 million loan from the
European Investment Bank
The European Investment Bank (EIB) is the European Union's investment bank and is owned by the 27 member states. It is the largest multilateral financial institution in the world. The EIB finances and invests both through equity and debt sol ...
(EIB) and financing and guarantees from
Export-Import Bank of Korea and K-Sure, also with participation from
Sumitomo Mitsui Banking Corporation
is a Japanese multinational banking financial services institution owned by the Sumitomo Mitsui Financial Group, which is also known as the SMBC Group. It is headquartered in the same building as SMBC Group in Marunouchi, Chiyoda, Tokyo, Japan. ...
,
Standard Chartered
Standard Chartered PLC is a British multinational bank with operations in wealth management, corporate and investment banking, and treasury services. Despite being headquartered in the United Kingdom, it does not conduct retail banking in th ...
,
Mizuho Bank
is the integrated retail and corporate banking unit of Mizuho Financial Group (; ). It is one of the largest financial services company in Japan with total assets of approximately $1.9 trillion USD in 2023, and considered one of Japan's three ...
,
Türkiye İş Bankası,
Garanti Bank and
Yapı ve Kredi Bankası. A hedging facility for the transaction is provided by some of the lenders as well as
Deutsche Bank
Deutsche Bank AG (, ) is a Germany, German multinational Investment banking, investment bank and financial services company headquartered in Frankfurt, Germany, and dual-listed on the Frankfurt Stock Exchange and the New York Stock Exchange.
...
.
Project segments
The project consists of three main segments:
;European side
Construction of five U-turns as underpasses and seven pedestrian crossings as overpasses along Kennedy Street that stretches between Kazlıçeşme and
Sarayburnu as a shoreline road beside the
Sea of Marmara
The Sea of Marmara, also known as the Sea of Marmora or the Marmara Sea, is a small inland sea entirely within the borders of Turkey. It links the Black Sea and the Aegean Sea via the Bosporus and Dardanelles straits, separating Turkey's E ...
. Widening of the entire Segment 1, which is approximately , from 3x2 lanes to 2x4 lanes.
;Bosphorus crossing
Construction of a , two-deck road tunnel with two lanes on each deck, a toll plaza and an administrative building on the western end and ventilation shafts on both ends of the tunnel.
;Asian side
Widening from 2x3 and 2x4 lanes to 2x4 and 2x5 lanes along an approximately stretch of the current D100 road that links at Göztepe to Ankara-İstanbul State Highway, and construction of 2 bridge intersections, 1 overpass and 3 pedestrian bridges.
Technical details
The American firm
Parsons Brinckerhoff was responsible for the design, while the British
Arup Group
Arup Group Limited, trading as Arup, is a British multinational professional services firm headquartered in London that provides design, engineering, architecture, planning, and advisory services across every aspect of the built environment. ...
and American
Jacobs Engineering Group
Jacobs Solutions Inc. is an American international technical professional services firm based in Dallas. The company provides engineering, technical, professional, and construction services as well as scientific and specialty consulting for a ...
undertook the technical and traffic studies and
HNTB
HNTB Corporation is an American infrastructure design firm. Founded in 1914 in Kansas City, Missouri, HNTB began with the partnership made by Ernest Emmanuel Howard with the firm Waddell & Harrington, founded in 1907.
One of the most trusted U. ...
provided independent design verification. The geotechnical survey was by the Dutch consultancy
Fugro
Fugro NV is a Dutch Multinational corporation, multinational public company headquartered in Leidschendam, Netherlands. The company is primarily a service company focused on geotechnical, survey and geoscience services, and is listed on Euron ...
.
The
tunnel boring machine
A tunnel boring machine (TBM), also known as a "mole" or a "worm", is a machine used to excavate tunnels. TBMs are an alternative to drilling and blasting methods and "hand mining", allowing more rapid excavation through hard rock, wet or dry so ...
(TBM) was supplied by the German manufacturer
Herrenknecht.
The Italian company Italferr was in charge of works management and project review on behalf of Administration. The French company
Egis Group
Egis is an international company active in the consulting, construction engineering and mobility service sectors that design and operate intelligent infrastructure and buildings. Egis operates in 100 countries and has 19,500 employees.
In the g ...
will be in charge of the operation and maintenance.
[Galante, Grace]
The Eurasia tunnel under the Bosphorus opens to the public.
''ccworldconstruction.com'', December 21, 2016.
The TBM section crossing the Bosphorus is long while another is constructed by the
New Austrian Tunnelling method (NATM) and
cut-and-cover
A tunnel is an underground or undersea passageway. It is dug through surrounding soil, earth or rock, or laid under water, and is usually completely enclosed except for the two Portal (architecture), portals common at each end, though ther ...
method. The tunnel's excavation diameter is ,
which allows an inner diameter of with -thick lining.
The tunnel alignment is located in a seismically active region, about to the North Anatolian Fault Zone. To decrease the seismic stresses/strains below the permissible levels, two flexible seismic joints/segments; with displacement limits of ± for shear and ± for extraction/contraction; were innovated, designed specially, localized through geological/geophysical/geotechnical conditions, tested in laboratory; implemented 'first time' in TBM tunnelling under similar severe conditions. The design earthquake magnitude was specified as moment magnitude of 7.25 and design of functional and safety evaluation earthquakes have a return period of 500 and 2,500 years, respectively. Seismic joint locations defined during design phase were verified through continuous monitoring of cutterhead torques.
The tunnel was excavated and constructed with a diameter Mixshield Slurry TBM exclusively designed and equipped with the latest } disc cutters (35 pieces monoblock disc cutters, all atmospherically changeable and have individual wearing sensor system), 192 piece cutting knives (only 48 atmospherically changeable), special pressurized locks for divers and material and rescue chamber for all shift members. Slurry Treatment Plant (installed power of which de-silts the bentonite slurry used during excavation and regenerates with capacity (approximately equivalent to ) was installed. The utilized TBM ranks first in the world with its cutterhead power, second with its pressure design; and sixth with its excavation area.
TBM operation was completed within ± tolerance in 479 calendar days, resulting in an average advance rate of ( for working days) by three crews 24/7. The maximum advance rate was realized at marine sediment zone with . Spent direct time for excavation and ringbuild were around 3,500 and 1,700 hours, respectively. In Trakya formation, 28 dyke zones were excavated with an average frequency of and thicknesses were varying between . Furthermore, 440 disc cutters, 85 scrapers and 475 brushes were replaced by TBM crew and four times hyperbaric maintenance operations (total of 45 days) with specially trained divers (max. under first time in the world) were successfully performed.
15,048 piece -thick precast segments (1,672 rings) with the high performance (average charge passed is 280
Coulomb
The coulomb (symbol: C) is the unit of electric charge in the International System of Units (SI).
It is defined to be equal to the electric charge delivered by a 1 ampere current in 1 second, with the elementary charge ''e'' as a defining c ...
(1,000 Coulomb limit) were produced and connected to each other by using 30,765 bolts. Each ring consists of nine segments that had an average 28 day cylinder compressive strength of and can resist at least 127 years as a service life against subsea conditions. Only 0.3% of produced segments were found to be deficient due to existence of cracks width more than .
On the other hand, twin tunnels (each has approximately length) were completed in 445 calendar days with a cross section of each by classical mining method. These tunnels were excavated in Trakya Formation from four faces with a /face advance rate under a densely populated district with minimum and maximum overburden of , respectively. Both tunnels met up each other within ± tolerance. The largest converge measured at the tunnel crown was (design tolerance is ) with a maximum surface settlement.
The tunnel is designed so that it has protected emergency areas every to provide shelter, also escape routes to the other tunnel level. Every there will be an emergency lane equipped with emergency telephone.
The speed limit in the tunnel route .
A daily average of around 120,000 cars and light vehicles was expected to pass through the tunnel after the first year, previous to its inauguration.
As of September 2022, the record set for daily vehicles transit was set on September 8 that year, counting up to 67,982 vehicles in a single day, still far from expectations, but being consider a proof of its success.
The toll is planned to be Turkish lira equivalent of US$4 plus
VAT for cars and US$6 plus VAT for minibuses in each direction. The toll rate will change in accordance with
US Consumer Price Index.
See also
*
Bosphorus Bridge, also called the First Bosphorus Bridge.
*
Bosphorus Strait
*
Fatih Sultan Mehmet Bridge
The Fatih Sultan Mehmet Bridge ("Sultan Mehmed the Conqueror Bridge"; , abbreviated as ''F.S.M. Köprüsü''), also known as the Second Bosphorus Bridge (), is a bridge in Istanbul, Turkey spanning the Bosphorus strait (Turkish: ''Boğaziçi'') ...
, also called the Second Bosphorus Bridge, located about 5 km north of the Bosphorus Bridge.
*
Great Istanbul Tunnel, a proposed undersea tunnel.
*
Marmaray, undersea rail tunnel, crossing the Bosphorus and connecting the Asian and European sides of Istanbul.
*
Public transport in Istanbul
Public transport in Istanbul comprises a bus network, various Rail transport, rail systems, funiculars, and sea, maritime services to serve the more than 15 million inhabitants of the city spread over an area of .
History
Public road transpor ...
*
Rail transport in Turkey
Turkey has a state-owned railway system built to standard gauge () which falls under the remit of the Ministry of Transport and Infrastructure (Turkey), Ministry of Transportation and Infrastructure. The primary rail carrier is the ''Türkiye C ...
*
Turkish Straits
The Turkish Straits () are two internationally significant waterways in northwestern Turkey. The Straits create a series of international passages that connect the Aegean and Mediterranean seas to the Black Sea. They consist of the Dardanelles ...
*
Yavuz Sultan Selim Bridge
The Yavuz Sultan Selim Bridge (), also known as the Third Bosphorus Bridge'','' is a vehicular bridge over the Bosphorus strait, to the north of Istanbul's two older suspension bridges, the 15 July Martyrs Bridge being the First Bosphorus Bridge ...
, also called the Third Bosphorus Bridge.
References
External links
*
*
Connecting Continents.'' in: ''All Around'', No. 4 / ''
Herrenknecht AG'', large-screen pics of the tunnel construction
{{Tunnels in Turkey
Undersea tunnels in Europe
Toll tunnels in Turkey
Tunnels in Istanbul
2016 in Istanbul
Bosphorus crossings
Undersea tunnels in Asia
2016 establishments in Turkey
Tunnels completed in 2016
Zeytinburnu
Kadıköy