The river then flows for a further a 4.4 km (2.7 mi) before draining into the Indian Ocean.

The Buddhist Amarapura Nikaya sect had its first upasampada (higher ordination ceremony) on a fleet of boats anchored upon the Madu Ganga in 1803.

The Buddhist Kothduwa temple is situated on an isolated island in the lake.

It's estuary and the many mangrove islets on it constitute a complex coastal wetland ecosystem.

The Madu Ganga Wetland was formally declared in 2003, in terms of the Ramsar Convention.