Proceedings of the 4th International Conference on Civil Engineering for Sustainable Development (ICCESD 2018), 9~11 February 2018, KUET, Khulna, Bangladesh (ISBN-978-984-34-3502-6) MORPHOLOGICAL RESPONSES OF A TIDAL RIVER DUE TO CLIMATE CHANGE: A CASE STUDY FOR KARNAFULI RIVER, BANGLADESH Sajal Kumar Roy1 and Umme Kulsum Navera2 1 Assistant Engineer, Bangladesh Water Development Board, Bangladesh, e-mail:
[email protected] 2 Professor, Department of Water Resources Engineering, BUET, Bangladesh, e-mail:
[email protected] ABSTRACT Karnafuli River is an important river in Bangladesh and Chittagong seaport plays the biggest role in this country’s economy. Navigability along the Seaport of Karnafuli River is dependent on the discharge and sediment transport with time. Sea Level Rise (SLR) and Temperature Rise (TMR) in the coast of Bay of Bengal are evident from different scientific reports. SLR is threatening the hydrodynamic and morphological behavior of coastal rivers including the navigability at the downstream of Karnafuli River. The backwater effects in terms of discharge and sediment transport have been carried out in this study. The future scenarios for rise in water level and temperature due to SLR and TMR have been projected for the next 25-30 years. Mathematical modeling has been carried out for 10cm, 25cm and 50cm SLR and 0.5°C, 1.5°C and 2.5°C TMR to assess the hydro- morphological responses. Morphological analysis has been carried out for three different conditions for mean sediment size d50=100, 150 and 200 µm. Mathematical model study has been performed 3- Dimensionally by using Delft3D. The study reach includes from downstream of Kaptai Dam to Kafco in Karnafuli River.