Ōmaumau River
Route of the Ōmaumau River
Mouth of the Ōmaumau River Show map of Auckland Ōmaumau River (New Zealand) Show map of New Zealand
Location
Country	New Zealand
Region	Auckland Region
Physical characteristics
Source
• coordinates	36°28′31″S 174°28′51″E / 36.4752°S 174.4809°E / -36.4752; 174.4809
Mouth	Kaipara Harbour
• coordinates	36°26′57″S 174°25′51″E / 36.4491°S 174.4309°E / -36.4491; 174.4309
Length	6 km (4 mi)
Basin features
Progression	Ōmaumau River → Kaipara Harbour → Tasman Sea

The Ōmaumau River is a middle order stream in the Auckland Region of New Zealand's North Island. It flows northwest to reach the Kaipara Harbour 20 kilometres (12 mi) northeast of Helensville. The catchment consists of rural pasture and fragmented native forest.

• List of rivers of New Zealand

• "Place name detail: Ōmaumau River". New Zealand Gazetteer. New Zealand Geographic Board. Retrieved 12 July 2009.
• Omaumau River - Land Air Water Aotearoa (LAWA)