ITU's 10 Recommendations for the Marine Mucilage Problem

Istanbul Technical University (ITU) researchers have released a technical assessment report presenting findings and potential solutions regarding the mucilage (sea snot) problem threatening the Sea of Marmara. The report includes views and recommendations from ITU faculty members Prof. İsmail Koyuncu, Prof. İzzet Öztürk, Prof. Mustafa Yanalak, Prof. Özcan Arslan, Assoc. Prof. Ebru Dülekgürken, Assoc. Prof. Mustafa Evren Erşahin and Dr. Türker Türken on the mucilage issue. The report contains analysis models related to mucilage formation and its harmful effects, and includes satellite imagery provided by the ITU Satellite Communications and Remote Sensing Centre (UHUZAM).

Technical report outlines causes of mucilage problem

According to current data, 53% of municipal wastewater from the Sea of Marmara basin is discharged after mechanical treatment, 42% after advanced biological treatment (C, N, P removal), and 5% after biological treatment (C, partial N, P removal). Based on modelling studies conducted in the Sea of Marmara and Istanbul Strait, to control eutrophication and prevent further deterioration of dissolved oxygen levels in deeper layers—in other words, to enable use of the receiving environment for purposes such as water sports and fishing—advanced biological treatment with C, N and P removal is recommended prior to all point source wastewater discharges into the Sea of Marmara, particularly from Istanbul. Over the past 10 years, biological N and P removal treatment applications prior to urban and industrial wastewater discharges into the Sea of Marmara, particularly from Istanbul, Izmit and Bursa, have accelerated. As a result of these applications, notable water quality improvements have been achieved, particularly in the Golden Horn, Izmit and Gemlik gulfs, and biodiversity has increased. However, in areas where discharge waters from the Yenikapı, Kadıköy, Küçükçekmece and Büyükçekmece Pre-treatment Facilities are released—north of the Büyükçekmece Baba Burnu to Tuzla Peninsula axis with limited water exchange, and the eastern region of Izmit Gulf—dissolved oxygen levels in deeper layers have been observed to be less than 2 mg/L.

Ten-point recommendations for addressing the mucilage problem

1. The Marmara Basin, encompassing the Sea of Marmara, the straits and sea connections, should be addressed and evaluated as a unified system.

2. An interdisciplinary science-based approach should be applied to reduce pollutant loads that increase mucilage formation processes in the Sea of Marmara, and collaboration between universities, public authorities, industry, private sector and NGOs should be strengthened.

3. Advanced biological treatment plant effluent should be maximally reused for irrigating urban green spaces (and agricultural areas where available) and/or industrial use, thereby reducing the volume of wastewater discharged into the Sea of Marmara.

4. Recovery should be prioritized at wastewater treatment facilities. In this context, innovative wastewater treatment processes that require minimal space and have high energy efficiency should be implemented.

5. Industrial zones and individual industrial facilities should be prevented from discharging priority and hazardous substances into municipal sewage networks through effective monitoring and inspection.

6. Ecological conditions in the upper layer of the Sea of Marmara should be supported. Fish migration between the Black Sea, Marmara and Aegean Sea should be facilitated by protecting fish spawning and refuge areas to ensure sustainability of these regions.

7. Water quality should be continuously monitored; monitoring, inspection and enforcement capacities for municipal and industrial wastewater discharges should be enhanced, deterrent penalties should be applied to facilities not operating in accordance with standards, and monitoring data should be shared.

8. Operation of advanced biological wastewater treatment facilities should be widely managed by specialized private sector firms under contracts of at least 8-10 years duration.

9. Satellite imagery at different spatial and temporal resolutions should be obtained, particularly for monitoring mucilage and pollution. Active satellite systems should be examined and integrated into the studies.

10. A dynamic Geographic Information System (GIS) should be established to serve as a decision support system for the Sea of Marmara and its basin. Current information should be continuously generated regarding the Sea of Marmara and its interacting areas; construction and changes in these areas should be identified; and impacts on the Sea of Marmara ecosystem should be determined.