Siri Waterfall, formerly called Santa Maria Waterfall, is a 120 m waterfall located about 3 km inland from the eastern coast of the island of Gaua in northern Vanuatu. The supply of water to the waterfall is from Lake Letas. This lake is a large freshwater lake located in the crater at the centre of the volcanic island, about 600 meters above sea level. Water flows from the lake 3 km east to the top of Siri Waterfall. After the waterfall, the water flows as a large stream, called Bē Solomul River (formerly Namang), for another 3 km before it reaches the sea. The large stream is known as "Big Water". A rough estimate of the water flow rate (during the dry season month of August 2006) was approximately 5 cubic metres per second.

Name

The name siri means ‘waterfall’ in the local Nume language. It is cognate with Vurës sēriv, Mwotlap na-syip , Mota siriv , Dorig sriv , Olrat siriv , Lakon hiriv , and Mwerlap siriw. All of these terms can be derived from Proto-Torres–Banks *siriβi ‘waterfall’.