Siri Waterfall, formerly called Santa Maria Waterfall, is a waterfall located about 3km 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 3km 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 3km 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’.

References