Trash skimmer boats have patrolled the Marmara Sea – where Türkiye’s big cities, including the most populated, Istanbul, are located – for the past nine months and picked some 53 tons of garbage from the sea. The campaign, organized by a private lender and an environmental nongovernmental organization, has recycled all the waste.

Entitled "Blue Breath," the campaign seeks to raise awareness of sea pollution and ways to clean it up.

The Marmara, an inland sea, is also among the busiest in Türkiye, which is littoral to the Mediterranean and Black seas. Connecting the Black Sea to the Aegean through the Bosporus and Dardanelles straits, the Marmara is both a gateway for vessels of all kinds and a host for beaches serving thousands in the Marmara region, the most crowded in Türkiye. Though it is small, with an area of 11,350 square kilometers (4,380 square miles) and with a depth reaching 1,370 meters (4,495 feet) at most, it is also among the most exposed to pollution. Untreated wastewater from cities with high populations and businesses in this main industrial region of the country aggravates the pollution.

Last year, the fallout from pollution manifested itself with mucilage, or sea snot, a thick layer of pollution covering the parts of the sea close to the shore. As a result of the overgrowth of microscopic algae called phytoplankton, which constitutes the first step of biological production in the sea, the thick, mucus-like slimy layer contains a variety of microorganisms. Mucilage formation, which is a secretion released into seawater in response to changes and anomalies in sea conditions, requires a stagnant sea as well as a high amount of nitrogen and phosphorus. A meticulous cleaning campaign overseen by the government removed the substance, though experts warn there is still the risk of a comeback if the pollution prevails.

The Turkish Marine Environment Protection Association (TURMEPA), in collaboration with Garanti BBVA bank, conducts cleaning campaigns in the Marmara and recently released a report on their work. The report says the collected waste is equivalent to waste produced daily by about 46,000 people. Some 17 tons of the collected waste are composed of plastic bags, bottles and other plastic waste. Textiles made up 4.8 tons of the waste, while metal made 4.4 tons. Another 4 tons of discarded fishing nets were collected in the nine months.

The campaign also reached out to middle school students to raise awareness about pollution and organized online lessons on global climate change, mucilage, zero waste, carbon emissions and the country's Sustainable Development Goals. The project will now be moved to the Mediterranean city of Antalya where a trash skimmer boat will clean up the coast of Adrasan, a popular vacation spot, for four months.

Embattled with pollution, the Marmara Sea, which serves a large population in Türkiye's northwest, faces a bleak future. Authorities and scientists hope a digital twin or a faithful, real-time visual representation of the sea could help them pinpoint risks and take the necessary steps in time to save it. Still recovering from the impact of last year’s large-scale mucilage issue, the sea’s marine life is threatened both by climate change and a backlog of years of pollution in one of Türkiye’s most industrialized regions. The government was already working on activating the digital twin and all of its modules are expected to be activated next year. The Ministry of Environment, Urban Planning and Climate Change has been working on the project for years and collecting data with a pollution monitoring program. The program involves 423 monitoring stations, 11 institutes and three research ships active through three-year periods, providing a comprehensive outline of the state of the sea.

Marine life flourishes at the bottom of the Marmara Sea, but the outlook is not so bright closer to the surface. To further improve the habitat, a project by nongovernmental organizations (NGOs) and universities boosted the number of gorgonian corals in the sea but elsewhere, worsening climate change has dealt a blow to fish in the Marmara, experts warn, urging protective measures.