The Istanbul Canal: a major environmental challenge

By Albane Rousseau
In the bustling city of Istanbul, a daring project is underway. President Recep Tayyip Erdogan is the driving force behind what he calls his “Crazy Canal Project”, a grandiose undertaking designed to relieve traffic on the Bosporus. Nevertheless, for Cemal Saydam, a retired oceanographer, “the proposed channel will not only affect Turkey but will cause an international environmental disaster that will affect the entire region”.
Ferry on the Bosporus. Credits: Albane Rousseau

The Bosporus is a strait, linking the Black Sea to the Sea of Marmara and separating Europe from Asia. Since 1936, Turkey has relied on the Montreux Convention, which gives it management of the Bosporus, to pursue a policy of balance in the Black Sea. The convention has safeguarded Russian interests by limiting NATO’s presence in the region, while preventing a substantial Russian naval presence in the Mediterranean, thus responding to Western concerns. It has always been of great commercial, military value and a crucial sea route for several countries. As a result, the Bosporus is subject to heavy maritime traffic, causing congestion, safety problems, and environmental hazards. 

Government’s solution? The construction of an artificial waterway. Stretching over 45 kilometers, the Crazy Canal is planned as a waterway running parallel to the Bosporus Strait, offering an alternative route for ships passing through Istanbul. The project calls for a navigable canal, flanked by state-of-the-art infrastructure and surrounded by ambitious real estate projects. The canal is one of Erdogan’s three main mega-projects, along with the construction of a third bridge over the Bosporus and a new airport.

Istanbul Canal project map. Credits: Foreign Policy

Protests and demonstrations erupted, highlighting concerns about the project’s environmental impact with the potential ecological destruction of the Marmara Sea. Professor Cemal Saydam, a veteran oceanographer from Hacettepe University in Ankara, regrets not having been consulted before the project was launched, “When a project involves merging two seas, marine science must be consulted right from the feasibility phase.” 

According to Cemal, if the Istanbul Canal project goes ahead, the balance between the cold, fresh waters of the Black Sea and the warm, salty waters that flow from the Mediterranean to the Black Sea via the Sea of Marmara could be upset. Construction of the canal would create a new water exchange route, which will alter natural circulation patterns and water characteristics in the region. “The Black Sea, situated approximately 30 cm higher than the Sea of Marmara, currently experiences two-way water exchange through the natural channel of the Bosporus. If the Istanbul Canal is constructed, it would create a one-way pathway for water transfer from the Black Sea to the Sea of Marmara,” he explains. As a result, the Black Sea would be continually forced to supply fresh water to the Sea of Marmara, without being replenished by the reverse flow of warm and salty waters from the latter.

In addition, the organic waste currently dumped in the Black Sea will end up in the Sea of Marmara, causing its death. “According to the EIA report, the amount of additional water coming from the Black Sea is 21 km3. If one-tenth of this volume is organic load, this represents 2.1 km3. Add to this the organic matter accumulated at the bottom of lakes Sazlıdere and Küçükçekmece. The Marmara Sea is already dying with 2.2 km3 of Istanbul’s load. It cannot support this additional 2 km3 load”, says Cemal. 

Consequences? As the Black Sea disappears, the Sea of Marmara will become a putrefied, irreversibly altered body of water. “The organic matter continues to decompose, again using oxygen, but this time from sulfate, and what remains is H2S, the smell of rotten eggs”, says Cemal before adding, “And the fish? You’ll say, “What was that?” No fish, no marine life.”

Moreover, Cemal also draws attention to a potential drawback: “The pros for the new channel suggest that the new channel will improve the traffic at Bosporus and decrease the risk of accidents. But no one mentions what might happen if an accident takes place at new channel. Just like the “Ever Given” accident at Suez Channel accidents may happen at the new channel. If similar accident takes place at a new channel this will result not only with the blockage of the entire channel but will immediately result with the formation of a new dam. The salvage operation will not be as easy as it happened at Suez Channel because it flows constantly and there exists about 30 cm height difference on average.”

Despite all of this, it is highly probable that the work will go ahead. The tender for construction companies has already been made public, and the environmental impact report has been accepted. A number of Istanbul residents, aware of the irreversible consequences and risks associated with the canal, are trying to prevent the work from going ahead. Zeynep Köseoglu (23), an Istanbul native currently studying psychology in Amsterdam, is one of the 70,000 people who signed a petition against the Istanbul Canal project in 2020. She explains, “Istanbul is going to ruin with this project. It’s not the only reason that made me leave Turkey, but it definitely contributed”. Indeed, the Turkish economy is already in a bad way, but with the construction of this huge project, it’s likely to get worse. Land speculation, particularly by investors from the “Gulf Emirates”, has already begun.

While the Istanbul Canal project promises to improve navigation, its potential environmental consequences cannot be overlooked. As the project continues to be debated and evaluated, it is essential to strike a balance between progress and environmental sustainability. An international environmental disaster is expected if the project goes ahead.