River, Bangladesh.
It is formed by the Surma River . Flowing south, it is joined southeast of Dhaka by the Padma River, which is formed from the waters of the Ganges and Brahmaputra rivers. After a course of about 164 mi (264 km) it empties into the Bay of Bengal through four mouths. A river of depth and velocity, it is navigable all year but often dangerous. At spring tide the sea rushes upriver in a single 20-ft (6-m) wave.