What you wonder about Marmaray: It is a project to provide railway transportation through the immersed tube tunnel under the sea in the Bosphorus. With the Marmaray project, Asia and Europe will be connected with an uninterrupted rail route.
What is the history of Marmaray?
The first railway tunnel to be crossed by the Bosphorus was prepared as a draft in 1860.
The idea about a railway tunnel under the Istanbul Strait was first proposed in 1860. But where the tunnel planned to pass under the Bosphorus would pass through the deepest parts of the Bosphorus, it would not be possible to build the tunnel above or under the seabed, using old techniques; and so this tunnel was planned as a tunnel over the columns built on the seabed in the design.
Such ideas and ideas were further evaluated in the following 20-30 year-round and a similar design was developed in 1902; in this design, a railway tunnel passing under the Bosphorus is envisaged; but in this design, a tunnel is placed on the seabed. Since then, many different ideas and ideas have been tried and new technologies have given more freedom to design.
In which countries are the projects which can be considered as the pioneer of Marmaray?
Under the Marmaray Project, the technique to be used for crossing the Bosphorus (immersed tube tunnel technique) 19. was developed from the end of the century. The first immersed tube tunnel, built in 1894, was built in North America for sewage purposes. The first tunnels built for traffic purposes using this technique were also built in the United States. The first is the Michigan Central Railroad tunnel, built during the 1906-1910 years.
In Europe, the Netherlands was the first to implement this technique; and the Maas Tunnel, which was built in Rotterdam, was opened in 1942. Japan was the first country to implement this technique in Asia, and the two-tube road tunnel (Aji River Tunnel) built in Osaka was commissioned in 1944. However, the number of these tunnels remained limited until a robust and proven industrial technique was developed in 1950; After the development of this technique, the construction of large-scale projects in many countries began.
When was the first report prepared for Istanbul?
The desire for the construction of a railway public transport link between the east and west of Istanbul and passing under the Bosporus has gradually increased in the early 1980 years, and as a result the first comprehensive feasibility study was conducted and reported. As a result of this study, it was determined that such a connection was technically feasible and cost effective and the route we saw in the project today was chosen as the best one among a number of routes.
- Year 1902… Sarayburnu - Uskudar (Strom, Lindman and Hilliker Design)
- Year 2005… Sarayburnu - Uskudar
The project, which was outlined in 1987, was discussed over the following years and it was decided to carry out more detailed studies and studies in 1995, and to update the feasibility studies, including passenger demand forecasts in 1987. These studies were completed in 1998 and the results showed that the results obtained previously were correct and the project would offer many advantages to the people working and living in Istanbul and to reduce the rapidly increasing problems related to traffic congestion in the city.
How is Marmaray financed?
In the 1999 Turkey and Japan Bank for International Cooperation (JBIC) financing agreement has been signed between. This loan agreement forms the basis of the projected financing for the Istanbul Bosphorus Crossing section of the Project.
BC1 and Engineering and Consultancy Services Loan Agreement
TK-P 15 Loan Agreement was signed between the Undersecretariat of Treasury and the Bank of Japan's International Cooperation Bank (JBIC) on 17.09.1999 and published in the official newspaper 15.02.2000 and 23965.
With this loan agreement, 12,464 Billion Japanese New loans were provided; 3,371 Billion for Japanese New Engineering and Consultancy Services, 9,093 Billion Japanese New Throat Tube is intended for Transition Construction.
Note Agreement and Loan Agreement on the second tranche of this loan, 18 On February 2005, negotiations between the Undersecretariat of Treasury and Japan Bank for International Cooperation (JBIC) have been completed in order to provide Official Development Assistance (ODA) loan from the Japanese Government. The Japanese Government has agreed to provide a long-term, low-interest loan of 98,7 billion Japanese Yen (approximately 950 million USD). Both loans have 7,5 interest and 10 year grace period and total 40 year term financing.
The agreement numbered TK-P15 contains the following important points:
The tender for Engineering and Consultancy Services and Railway Bosphorus Tube Crossing Work has been decided to be conducted according to the rules of Japanese credit institution JBIC. Only the companies of the countries designated as eligible source countries can participate in the auctions to be financed by loan revenues.
The eligible countries for the construction tender are the countries listed in Japan and the Help List - Section 1 and Section - 2, which are generally outside the US and European countries.
All important stages of the tender and contractual specifications are required to be approved by the Japanese Credit Agency.
It is foreseen that the Project will be established by the Ministry of Transport (PIU), which will be responsible for the construction and design phases of the tender and the completion of the operation and maintenance phases after the completion of the construction.
CR1 Loan Agreements
22.693 TR Loan Agreement; The decision of the Council of Ministers dated 650 / 200 / 22 and numbered 10 / 2004 was signed between the Undersecretariat of Treasury and the European Investment Bank (EIB) on the entry into force of the first tranche of 2004 Million Euro, the portion of the 8052 Million Euro.
This loan has a floating interest rate and 15 2013 is a non-repayable 22 year term.
23.306 TR Loan Agreement; The decision of the Council of Ministers dated 650 / 450 / 20 and numbered 02 / 2006 was signed between the Undersecretariat of Treasury and the European Investment Bank (EIB) on the entry into force of the second tranche of 2006 Million Euro, which is the second tranche of the 10099 Million Euro.
This loan has a floating interest rate and will be repaid in 8 monthly periods after 6 year after the use of the credit tranche.
The 1 Million of the CR650 business was obtained from the European Investment Bank. The remaining 217 Million Euro was signed with the Council of Europe Development Bank on 24.06.2008. Thus, the 1 of the loan required for the CR100 Business was obtained.
CR2 Loan Agreements
Studies have shown that there is a need for 440 tools for the Project.
23.421 TR Loan Agreement; The Undersecretariat of the Treasury and the European Investment Bank (EIB) signed the decision of the Council of Ministers dated 400 / 14 / 06 and numbered 2006 / 2006 on the entry into force of the 10607 Million Euro contract.
This loan has a floating interest rate and will be repaid in 8 monthly periods after 6 year after the use of the credit tranche.
What are the objectives of the Marmaray Project?
With this project, as a result of the extensive scientific studies carried out in Istanbul since 1984, a project that combines the existing Suburban Railway lines with a tube tunnel under the Bosphorus has emerged with the project of a “Bosphorus Railway Crossing ecek that will be integrated with the existing rail systems in the city. .
In this way; Istanbul Metro will be integrated with Yenikapi and passengers will be able to travel to Yenikapi, Taksim, Sisli, Levent and Ayazaga with a reliable, fast and comfortable public transport system.
Kadıköy- By integrating with the Light Rail System to be built between Kartal, passengers will be able to travel with a reliable, fast and comfortable public transportation system, and the share of Rail Systems in urban transportation will increase. Most Importantly, by connecting Europe and Asia by rail, it is high between Asian and European sides.
capacity of public transport will be provided, contribution will be provided to the protection of the historical and cultural environment, no change will be made in the general structure of the Bosphorus, the marine ecological structure will be preserved,
With the launch of the Marmaray project, Gebze Halkalı 2-10 will be carried out once a minute and the capacity to carry 75.000 passengers per hour in one direction will be shortened, Travel times will be shortened, the load of the existing Bosphorus Bridges will be lightened, providing easy, convenient and quick transportation to the business and cultural centers and bringing the city's economic life closer to each other. It will fold.
What measures were taken against the earthquake in the Marmaray Project?
Istanbul is about 20 kilometers from the North Anatolian Fault Line extending from the east to the southwest of the Islands in the Marmara Sea. Therefore, the project area is located in a region that requires the consideration of a major earthquake risk.
It is known that many similar types of tunnels around the world are exposed to earthquakes - similar in size to the expected size - and survived these earthquakes without major damage. Kobe Tunnel in Japan and Bart Tunnel in San Francisco, USA are examples of how robust these tunnels can be built.
In addition to the available data, the Marmaray Project will collect additional information and data from geological, geotechnical, geophysical, hydrographic and meteorological surveys and surveys, and these data will serve as the basis for the design and construction of tunnels to be constructed using the latest and modern civil engineering technologies.
Accordingly, the tunnels within the scope of this project will be designed in such a way as to be able to withstand an earthquake with the highest severity expected in the region.
The most recent experience of the seismic event in 1999 in the Bolu region of Izmit has been solved, and these experiences will form part of the foundations on which the design of the Istanbul Bosphorus Crossing Railway Project is based.
Some of the best national and international experts participated in the studies and evaluations. the earthquake in Japan and the United States District was built previously in many similar tunnel and therefore especially Japanese and American experts, the specifications must be met in the design of the tunnel for the development of the number of scientists with and expert in Turkey is working in close cooperation.
Turkish scientists and experts have been working extensively on identifying the characteristics of potential seismic events; and based on all the information up to date and historical data collected in Turkey - Bolu Izmit region derived from the events of the year 1999, including the most recent data - has been analyzed and used.
Japanese and American experts assisted in this data analysis study and supported relevant activities; these experts have also included all of their extensive knowledge and experience in the design and construction of seismic and flexible joints in tunnels and other structures and stations within the scope of the specifications to be met by the Contractors.
Large earthquakes can cause serious damage to large infrastructure projects if the effects of such earthquakes are not adequately considered within the scope of the design. Therefore, the most advanced computer-based models to be used in the Marmaray Project and America, the best experts from Japan and Turkey will participate in the design process.
Thus, the team of experts, which forms part of the Avrasyaconsult organization, can be prevented from turning into worst-case conditions (ie a major earthquake in the Marmaray area), to ensure that this event can be prevented from turning into a disaster for people who have gone through tunnels or working in tunnels. will be able to provide support and advice on this issue.
The upper blue part of this map is the Black Sea and the central part is the Sea of Marmara connected by the Bosphorus. The North Anatolian Fault Line will be the center of the next earthquake in the region; this fault line extends in the east / west direction and passes approximately 20 kilometers south of Istanbul.
As can be seen from this map, the southern parts of the Sea of Marmara and Istanbul (upper left corner), is located in one of Turkey's most active earthquake zones. Therefore, tunnels, structures and buildings will be constructed in such a way that no destructive damage or damage occurs in case of an earthquake.
Will Marmaray harm the cultural heritage?
Göztepe Station is one of many examples of old buildings to be protected.
In Istanbul, the history of civilizations that lived in the past is based on an approximate 8.000 year.
Therefore, the ancient ruins and structures, which are expected to exist under the historic city, have a huge archaeological importance all over the world.
In contrast, during the construction of the Project, it will not be possible to ensure that some historical buildings are not affected; in the same way it is not possible to prevent some deep excavations for new stations.
For this reason, different organizations and organizations involved in major infrastructure projects, such as the Marmaray Project, under this special obligation; buildings and structures, construction works and architectural solutions will be planned and designed in such a way that they will not harm the old buildings and the historical areas under the ground. In this respect, the Project is divided into two separate parts.
The existing section of the improvement of the existing suburban railways (aboveground of the project) will be made on the current route and therefore no deep excavations will be required here. It is expected that only buildings that form part of the existing railway system will be affected by the construction work; where such buildings (including stations) are classified as Historic Buildings, these buildings shall be kept in place, moved to another location or replica copies shall be constructed.
In order to minimize the impacts on the potential underground historical assets, the Marmaray Project planning team acted in cooperation with the relevant institutions and organizations and planned the route of the railway line in the most appropriate way; thus the areas to be affected are minimized. In addition to these, extensive studies have been conducted on the available information on the areas that may be affected and are still ongoing.
There are many old houses of historical value in Istanbul. Marmaray Project has been planned as necessary to keep the houses to be affected by construction works in a very limited number. A conservation plan will be prepared for each case and each house will be protected on site, moved to another location, or a replica copy will be built.
The Council for the Protection of Cultural and Natural Assets reviewed the final plan of the project and expressed its views and comments.
In addition, as required by DLH, the contractor who carried out the excavations commissioned two full-time history experts to monitor all activities during the construction of the excavation works. One of these experts is Ottoman historian and the other is a Byzantine historian. These experts were supported by other experts who participated in the planning process. These historians have ensured the maintenance of relations with the three local Cultural and Natural Heritage Boards and Commissions on Monuments and Archaeological Resources.
Excavation excavations under the supervision of the Istanbul Archeology Museum have been going on since the 2004 and Marmaray construction works are carried out only within the framework of the permits given by the Protection Boards.
Historical artifacts were found, these were reported to the Istanbul Archeology Museum, and the museum officials visited the site in any case and decided on the work to be done to protect the finds.
Anything that can be done under reasonable circumstances to protect important historical and cultural assets in the old city of Istanbul has been planned and planned in this way. specifications provided for Contractors, Contractors DLH related commissions and encouraged to work together with museums and so on cultural heritage assets, Turkey and the people living in all other regions of the world and has provided protection for the benefit of future generations.
There are many old houses of historical value in Istanbul. Marmaray Project has been planned as necessary to keep the houses to be affected by construction works in a very limited number. A conservation plan will be prepared for each situation and each house will be protected on site, moved to another location, or a one-to-one copy will be built.
What is Immersed Tube Tunnel?
A Submerged Tunnel consists of several elements produced in a dry dock or a shipyard. These elements are then drawn to the site, immersed in a channel and connected to form the final state of the tunnel. In the figure below, the element is carried by a catamaran docking barge to a submerged location. (Tama River Tunnel in Japan)
The above picture shows the outer steel tube envelopes produced in a shipyard. These tubes are then pulled like a ship and moved to a site where the concrete will be filled and completed (pictured above) [South Osaka Port in Japan (along rail and road) Tunnel] (Kobe Port Minatojima Tunnel in Japan).
Above; Kawasaki Harbor Tunnel in Japan. Right; South Osaka Harbor Tunnel in Japan. Both ends of the elements are temporarily closed by partition sets; thus, when water is released and the pool used for the construction of the elements is filled with water, these elements will be allowed to float in the water. (Photographs taken from a book published by the Association of Japanese Screening and Reclamation Engineers.)
The length of the immersed tunnel at the seabed of the Bosphorus will be approximately 1.4 kilometers, including the connections between the immersed tunnel and the drilling tunnels. The tunnel will be a vital link in the two-lane railway crossing below the Bosphorus; this tunnel will be located between the Eminönü district on the European side of Istanbul and the Üsküdar district on the Asian side. Both railway lines shall extend within the same binocular tunnel elements and be separated from each other by a central separation wall.
Over the course of the twentieth century, more than one hundred tunnels were built for road or rail transport around the world. Immersed tunnels were built as floating structures and then submerged in a pre-screened canal and covered with a cover layer. These tunnels must have a sufficient level of effective weight to prevent them from floating again after installation.
Immersed tunnels are formed from a series of tunnel elements that are produced in prefabricated lengths of substantially controllable length; each of these elements is generally of the length 100 m, and at the end of the tube tunnel, these elements are connected under the water to form the final version of the tunnel. Each element is provided with a temporary set of insertion kits at the ends; these sets allow the elements to float when they are dry. The fabrication process is completed in a dry dock, or the elements are lowered to the sea as a vessel and then completed in a floating place near the final assembly.
The immersed tube elements produced and completed in a dry dock or at a shipyard are then drawn to the site; immersed in a channel and connected to form the final state of the tunnel. On the left: The element is pulled to a place where final assembly operations will be carried out for immersion in a busy port. (Osaka South Harbor Tunnel in Japan). (Photo taken from the book published by the Japanese Association of Screening and Breeding Engineers.)
Tunnel elements can be successfully pulled over large distances. After the equipment operations are carried out in Tuzla, these elements will be fixed to the cranes on the specially constructed barges, which will enable the lowering of the elements to a prepared channel at the seabed. These elements will then be dipped, giving the weight required for the lowering and dipping process.
The immersion of an element is a time-consuming and critical activity. In the upper and right illustrations, the element appears when the element is submerged downwards. This element is controlled horizontally by anchors and cable systems and the cranes on the immersion barges control the vertical position until the element is lowered and fully seated on the foundation. In the picture below, GPS tracking of the position of the element is observed during immersion. (Photos are taken from the book published by the Association for Japanese Screening and Reclamation Engineers.)
The immersed elements will be brought together end-to-end with the previous elements; the water between the connected elements will then be discharged. As a result of the water discharge process, the water pressure at the other end of the element will compress the rubber gasket, thereby making the gasket waterproof. Temporary supports will hold the elements in place while the foundation under the elements is completed. The channel will then be refilled and the required protection layer will be added thereto. After inserting the tube tunnel end member, the junction points of the drilling tunnel and the tube tunnel shall be filled with filling materials that provide waterproofing. Tunneling Machines (TBMs) will continue to drill through the immersed tunnels until the immersed tunnel is reached.
The top of the tunnel will be closed with backfill to ensure stability and protection. In all three illustrations, backfilling from a self-propelled double-jaw barge by applying the tremi method is shown. (The photographs were taken from the book published by the Japanese Association of Screening and Reclamation Engineers)
There will be two tubes in the submerged tunnel at the bottom of the throat, one for each one-way train navigation.
The elements will be completely buried in the seabed so that after construction the seabed profile will be the same as the seabed profile before the construction started.
One of the advantages of the immersed tube tunnel method is that the cross section of the tunnel can be arranged in the most appropriate way within the specific needs of each tunnel. In this way, you can see the different cross sections used throughout the world in the picture on the right.
Immersed tunnels were constructed as reinforced concrete elements, which had previously been fitted with internal and external reinforced concrete elements, with or without dental steel envelopes. In contrast, since the nineties
In Japan, innovative techniques are applied using non-reinforced but ribbed concretes prepared by sandwiching between internal and external steel envelopes; these concretes are structurally completely composite. This technique could be implemented with the development of excellent quality fluid and compacted concrete. This method can eliminate the requirements related to the processing and production of iron bars and molds, and in the long term, by providing adequate cathodic protection for steel envelopes, the collision problem can be eliminated.
How to use drilling and other tube tunnel?
The tunnels below Istanbul will consist of a mixture of different methods. The red section of the route will consist of an immersed tunnel, the white sections will be built as a bored tunnel using mostly tunnel boring machines (TBM), and the yellow sections will be built using the cut-and-cover technique (C&C) and the New Austrian Tunnel Boring Method (NATM) or other traditional methods. . Tunnel Boring Machines (TBM) are shown with numbers 1,2,3,4, 5, XNUMX, XNUMX and XNUMX in the figure.
Drilling tunnels opened on the rock by using tunneling machines (TBMs) will be connected to the immersed tunnel. There is a tunnel in each direction and a railway line in each of these tunnels. Tunnels were designed with sufficient distance between each other in order to prevent them from affecting each other significantly. In order to provide the possibility of escape to the parallel tunnel in an emergency, short connection tunnels have been constructed at frequent intervals.
The tunnels beneath the city will be connected to each other at every 200 meter; so that service personnel can easily switch from one channel to another. Furthermore, in the event of an accident in any of the drilling tunnels, these connections will provide safe recovery means and provide access for rescue personnel.
In tunneling machines (CPCs), the latest 20-30 is widely observed throughout the year. The illustrations show examples of such a modern machine. The diameter of the shield can exceed 15 meters with current techniques.
The operation of modern tunnel boring machines can be quite complex. The picture uses a three-faceted machine, which is used in Japan, to open an oval-shaped tunnel. This technique can be used where it is necessary to construct station platforms.
Where tunnel section changes, other methods can be applied in combination with several specialized procedures (New Austrian Tunneling Method (NATM), drilling-blasting and gallery opening machine). Similar procedures will be used during the excavation of the Sirkeci Station, which will be organized in a large and deep gallery opened underground. Two separate stations will be constructed underground using open-close techniques; These stations will be located in Yenikapı and Üsküdar. Where open-close tunnels are used, these tunnels shall be constructed as a single box cross-section in which a central separating wall is used between the two lines.
In all tunnels and stations, water insulation will be done and ventilation will be established to prevent leaks. Design principles similar to the principles used for underground subway stations will be used for suburban railway stations.
Where cross-link traverse lines or lateral connection lines are required, different tunneling methods can be combined. In this tunnel, TBM technique and NATM technique are used.
How will excavation work be carried out in Marmaray?
Grabbing dredges will be used to make part of the underwater excavation and dredging works for the tunnel channel.
Immersed Tube Tunnel will be placed on the sea floor of Istanbul Strait. For this reason, a channel large enough to contain the structural elements will have to be opened on the seabed; furthermore, this channel will be constructed so that a covering layer and protective layer can be placed on the tunnel.
The underwater excavation and dredging works of this canal will be carried out down the surface using heavy underwater excavation and dredging equipment. It was calculated that the total amount of soft soil, sand, gravel and rock to be extracted would exceed 1,000,000 m3.
The deepest point of the route is located in the Bosphorus and has a depth of about 44 meters. Immersed Tube At least one 2 meter protective layer shall be placed on the tunnel and the cross section of the tubes shall be approximately 9 meters. Thus the working depth of the dredger will be about 58 meters.
There are a limited number of different types of equipment to ensure this is achieved. These works will most likely be used in the grabbing dredger and the towing bucket.
The grabbing dredger is a very heavy vehicle placed on a barge. There are two or more buckets, as can be seen from the name of this vehicle. These buckets are scoops that are opened when the device is lowered down from the barge and suspended and suspended from the barge. Since the buckets are very heavy, they sink to the bottom of the sea. When the bucket is lifted upwards from the bottom of the sea, it closes automatically, so that the tools are moved to the surface and emptied on the barges by means of buckets.
The most powerful shovel dredgers have the capacity to dig around 25 m3 in a single working cycle. The use of grabbing combs is most useful in soft to medium hard materials and cannot be used on hard tools such as sandstone and rock. Grab dredges are one of the oldest types of dredgers; but they are still widely used worldwide for this type of underwater excavation and survey work.
If the contaminated soil is to be scanned, some special rubber seals may be attached to the buckets. These seals will prevent the release of the sludge and the fine particles to the water column during the pull-up of the bucket from the sea bottom, or to keep the amount of particles released at very limited levels.
The advantages of the bucket are that it is very reliable and can perform excavation and screening works at high depths.
The disadvantages are that the depth of the excavation increases dramatically as depth increases, and the flow in the Bosphorus will affect the level of accuracy and overall performance. In addition, excavation and screening cannot be performed on scoops and hard tools.
The Pull Bucket Dredger is a special ship mounted with a plunging type screening and cutting device with a suction pipe on it. While the vessel is on the route, the water mixed with the water is pumped into the ship from the bottom of the sea. Deposits must be deposited in the vessel. In order to fill the vessel at maximum capacity, it should be ensured that the high amount of residual water can flow out of the ship while the ship is moving. When the vessel is full, it goes to the waste disposal area and empties the waste; after this operation, the vessel will be ready for the other operating cycle.
The most powerful Traction Bucket Vessels are capable of picking up about 40,000 tonnes (about 17,000 m3) in a single working cycle and digging and scanning up to a depth of about 70 meters. Traction Bucket Vessels can dig and crawl in soft to medium hard materials.
Advantages of Pull Bucket Dredger; high capacity and mobile system does not rely on anchor systems. The disadvantages are; the lack of accuracy and the excavation and screening of these vessels in the areas close to the shore.
In the terminal connection joints of the submerged tunnel, some rock will have to be excavated and scanned in areas near the shore. Two different ways can be followed in order to perform this process. One of these ways is the implementation of the standard method of underwater drilling and blasting; the other method is the use of a special chiseling device that allows the rock to break apart without blasting. Both methods are slow and costly. If the drilling and blasting method is preferred, some special measures will be required to protect the environment and the surrounding buildings and structures.
Will the Marmaray project harm the environment?
Many studies have been carried out by the universities in order to understand the characteristics of the marine environment in the Bosphorus. Within the framework of these studies, construction works to be carried out will be arranged in a way that will not prevent the migration of fish in the Spring and Autumn seasons.
While evaluating the environmental impact of major infrastructure projects such as the Marmaray Project, the impacts occurring in two different periods as a general practice are evaluated; impacts during the construction process and the effects after the opening of the railway.
The impacts of the Marmaray Project are similar to those of other modern projects in recent years in Europe, Asia and the Americas. In general, it can be said that the effects that occur during the construction process are negative; however, these shortcomings will become completely ineffective soon after the system is put into operation. On the other hand, the impacts that will occur during the rest of the life of the project will be very positive compared to the situation we are in today if nothing is done, ie if the Marmaray Project is not undertaken.
For example, when we compare the situations that would occur if we did not realize the Project and the situation that would arise if we did not, the reduction in air pollution as a result of the Project is estimated to be approximately the following levels:
- In the amount of air pollutant gases (NHMC, CO, NOx, etc.), during the first 25 annual operating period, there will be an annual average reduction of approximately 29,000 ton / year.
- During the first 2 annual operating period in the amount of greenhouse gases (mainly CO25), there will be a decrease of approximately 115,000 tons / year on average annually.
All these types of air pollution have negative effects on the global and regional environment. Non-methane hydrocarbons and carbon oxides contribute positively to general global warming (creating a greenhouse effect and also CO is a highly toxic gas) and is very uncomfortable for people with nitrogen oxides, allergic reactions and asthma.
Once operational, the Project will reduce negative environmental problems such as noise and dust, which have affected Istanbul as a result of modern and effective techniques. In addition, the Project will make rail transport much more reliable, safe and comfortable. However, in order to achieve these great environmental benefits, there is a provision that must be paid initially; these are the negative effects that we will encounter during the construction of the Project.
The negative impacts to be experienced during construction in terms of people living in the city and the city are presented below:
Traffic Congestion: In order to build three new deep stations, very large construction sites in the heart of Istanbul will have to be occupied. The traffic flow will be diverted in other directions; but sometimes there will be traffic congestion problems.
During the construction of the third line and the improvement of existing lines, existing commuter rail services will have to be limited and even cut for certain periods. Alternative transport methods such as bus services will be provided to provide services in these affected areas. These services can lead to traffic congestion problems during these periods, as the traffic flow in the affected station areas is diverted in other directions.
Contractors, equipment and materials in large trucks to be moved to the construction site and to be removed from there, they will have to use the highway systems near the deep stations; and these activities will cause overload of the capacity of road systems from time to time.
It will not be possible to completely prevent interruptions; however, the possible negative impacts may be limited by careful planning and the provision of comprehensive information to the public and by obtaining the necessary support from the relevant authorities.
Noise and Vibrations: The works that must be carried out for the Marmaray Project consist of noisy activities. In particular, the work to be done for the construction of deep stations will cause a high level of uninterrupted daily noise during the construction phase.
Underground work will not cause noise in the city under normal circumstances. In contrast, tunneling machines (CPCs) will cause low frequency vibration on the ground around them. This will cause noise in the surrounding buildings and terrains, and this noise may continue uninterruptedly for 24 hours, but such noises will not affect any area for more than a few weeks.
In order to prevent the closure of existing suburban rail services over a long period of time, some work will be carried out during the night. The activities to be carried out within these periods can be expected to be quite noisy. This noise level may occasionally exceed the limit levels acceptable for such work under normal circumstances.
It will not be possible to completely eliminate the disturbances caused by noise, but a wide range of specifications has been envisaged for the measures to be taken by the Contractors in order to limit the noise level as a result of construction activities.
Dust and Sludge: Construction activities cause dust in the areas around the construction sites and sludge and soil accumulation on roads. These conditions will be observed in the Marmaray Project.
Although it is not possible to eliminate these problems altogether, many things can and will be done in order to reduce the effects; watering, for example, roads and coated areas; cleaning of vehicles and roads.
Service Outages: Before starting construction work, all known infrastructure networks will be identified and their locations and directions will be changed as necessary. In contrast, many of the existing infrastructure networks cannot be deployed as they should; and, in some cases, infrastructure lines that are not within the knowledge of anyone. Therefore, it will not be possible to prevent any interruption of service interruptions from time to time in communication systems such as power supply, water supply, sewerage systems and telephone and data cables.
Although it is not possible to completely prevent such interruptions, negative impacts can be limited by careful planning and by providing comprehensive information to the public and by obtaining the necessary support from the relevant authorities.
Some adverse effects will be observed during the construction phase in terms of the people using the marine environment and the sea road in the Bosphorus. The most important of these effects are:
Contaminated Materials: In the studies and investigations carried out in the Bosphorus, it is documented that there are contaminated materials at the seabed where the Golden Horn joins the Bosphorus. The amount of contaminated material to be removed and removed is about 125,000 m3.
As required by DLH from Contractors, it is necessary to use proven and internationally recognized techniques for the removal of equipment from the sea bottom and for transport to a Closed Waste Removal Facility (CDF). These facilities will consist of an enclosed space, which is typically covered by limited protective equipment on the seabed or surrounded by confined and controlled and clean materials on the terrestrial area, or on a restricted area.
If the correct methods and equipment are used in the relevant work and activities, the pollution problems can be completely eliminated. In addition, the removal of contaminated equipment from a significant part of the seabed area will have a positive impact on the marine environment.
Turbidity: At least 1,000,000 m3 soil must be removed from the bottom of the Bosphorus in order to prepare the opened channel in accordance with the immersed tube tunnel. These works and activities will undoubtedly cause the formation of natural sediments in water and consequently increase turbidity. This will have negative effects on fish migration in the Bosphorus.
In the spring, fish move to the north by moving deep into the Bosphorus, where the current flows towards the Black Sea, and migrate to the south in the upper layers where the current flows towards the Sea of Marmara.
In contrast, since these inverse currents form relatively uninterruptedly and simultaneously, the cloud strip in the water resulting from an increase in turbidity level is expected to be relatively narrow (probably about 100 to 150 meters). As in the case of the Oeresund Immersed Tube Tunnel between Denmark and Sweden, this has also been observed in other similar projects.
If the resulting turbidity strip is less than 200 meters, it is unlikely to have a significant effect on fish migration. Because the migratory fish will have the opportunity to find and follow the paths where the turbidity does not increase in the Bosphorus.
It is possible that these negative effects on fish can be eliminated almost completely. The mitigation which may be applied for this purpose shall be limited to limiting the options of the Contractors regarding the timing of the dredging works. Thus, contractors will not be allowed to perform underwater excavations and dredging in deep parts of the Bosporus during the spring migration period; Contractors will only be able to perform screening works provided that 50% of the width of the Bosphorus is not exceeded during the Autumn migration period.
A large part of the sea works and activities related to the construction of the submerged tube tunnel are located in the Bosphorus. Most of these activities can be carried out in parallel to normal sea traffic in the Bosphorus of Istanbul; however, there will be some periods in which sea restrictions will be imposed, and in some cases even shorter periods in which traffic will be stopped. The mitigation measure that can be applied will be to work in close cooperation with the Port Authority and other competent institutions, to ensure that all works and activities in the sea are planned in a careful and timely manner. In addition, all possibilities for the availability of modern Ship Traffic Control and Monitoring Systems (VTS) will be investigated and implemented.
Pollution There will always be an accident risk that can lead to pollution problems during periods of heavy and intensive work and activities at sea. Under normal circumstances, these accidents will cover a limited amount of oil or gasoline spills on the Bosphorus waterway or the Sea of Marmara.
Such risks cannot be completely eliminated; however, contractors must strictly adhere to internationally proven standards and be prepared to deal with relevant problems to limit or neutralize the environmental impacts of such situations.
How many stations will the Marmaray project be?
Three new stations in the Bosphorus Crossing section of the project will be constructed as deep underground stations. These stations will be designed in detail by the Contractor, who will act in close cooperation with the relevant Competent Authorities, including DLH and Municipalities. All three of these stations will have their main concave underground and only their entrances will be visible from the surface. Yenikapı will be the largest transfer station on the Project.
43.4 km on the Asian side and 19.6 km on the European side, covering the improvement of existing suburban lines and converting them to the surface subway. In total, 2 stations will be renewed and turned into modern stations. The average distance between stations is planned as 36 - 1 km. The number of existing lines will be increased to three and the system will consist of 1,5 lines, T1, T2 and T3. The T3 and T1 lines will operate on Commuter (CR) Trains, while the T2 line will be used by Intercity freight and passenger trains.
Kadıköy- The Eagle Rail System Project and Marmaray Project will also be integrated into the İbrahimağa Station, so that passenger transfer can take place between the two systems.
The minimum curve on the line is 300 meter, the maximum vertical line slope outline is provided as% 1.8 to be suitable for the operation of passenger and freight trains. While the project speed is planned as 100 km / h, the average speed to be reached in the enterprise is estimated to be 45 km / h. The platform length of the stations is projected as 10 meters in accordance with the passenger loading and unloading of the metro series consisting of 225 vehicles.
Marmaray Frequently Asked Questions
[ultimate-faqs include_category = 'marmaray']