Waikouaiti River
{{Short description|River in Otago, New Zealand}}
{{Use dmy dates|date=July 2019}}
{{Use New Zealand English|date=February 2024}}
{{Infobox river
| name = Waikouaiti River
| image = NZ-WaikouaitiBridge.jpg
| image_size =
| image_caption = State Highway 1 crosses the Waikouaiti River between Waikouaiti and Karitane
| map = {{Maplink|frame=yes|type=line|plain=yes|zoom=9|frame-align=center|frame-width=270|frame-height=270|stroke-color=#0000ff|stroke-width=2}}
| map_size =
| map_caption = Route of the Waikouaiti River
| map_alt =
| pushpin_map = New Zealand#New Zealand South Island
| pushpin_map_size = 270px
| pushpin_map_caption = Mouth of the Waikouaiti River
| pushpin_map_alt =
| source1 = Macraes {{small|(North Branch)}}
| source1_location =
| source1_coordinates = {{coord|-45.3908|170.4263|type:river_region:NZ|display=inline}}
| source1_elevation =
| source2 = The Silverpeaks {{small|(South Branch)}}
| source2_location =
| source2_coordinates = {{coord|-45.7481|170.4618|type:river_region:NZ|display=inline}}
| source2_elevation =
| mouth_location = Pacific Ocean
| mouth_elevation =
| mouth_coordinates = {{coord|-45.640088|170.661707|region:NZ|format=dms|display=inline,title}}
| subdivision_type1 = Country
| subdivision_name1 = New Zealand
| length =
| discharge1_avg =
| basin_size =
| progression = Waikouaiti River → Pacific Ocean
| tributaries_left = Murphys Creek {{small|(North Branch)}}, Toll Bar Creek {{small|(South Branch)}}, Sluice Box Creek {{small|(South Branch)}}, Mount Misery Creek {{small|(South Branch)}}
| tributaries_right = Back Creek {{small|(North Branch)}}, Deep Creek {{small|(North Branch)}}, Dip Creek {{small|(North Branch)}}
| waterfalls =
| bridges =
}}
File:Karitane port.JPG; fishing wharf and channel to the Pacific Ocean at right, Matanaka headland at left background.]]
The Waikouaiti River is found to the north of Dunedin in Otago, New Zealand.{{Cite web|title=Environmental monitoring data for Waikouaiti River|url=https://www.lawa.org.nz/explore-data/otago-region/river-quality/waikouaiti-river/|access-date=2021-05-23|website=Land, Air, Water Aotearoa (LAWA)}} It flows to the Pacific Ocean at Karitane, close to the town of Waikouaiti.{{Cite web|date=2015-07-07|title=Locals help restore the Waikouaiti River in Otago|url=https://tindall.org.nz/locals-help-restore-the-waikouaiti-river-in-otago/|access-date=2021-05-23|website=The Tindall Foundation|language=en}}
The Waikouaiti River is the largest river in East Otago.{{Cite web|last=|first=|date=2021|title=Waikouaiti River at Bucklands|url=https://www.theswimguide.org/beach/6218|access-date=2021-05-23|website=Swim Guide}}