Shag Lake

{{Use New Zealand English|date=April 2024}}

{{Use dmy dates|date=July 2019}}

{{Infobox body of water

|name = Shag Lake

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|pushpin_map=Northland

| pushpin_map_alt = Location of Shag Lake

|location = Northland Region, North Island

|coords = {{coord|35.7911341|S|173.6075693|E|type:waterbody|display=title,inline}}

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|basin_countries = New Zealand

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Shag Lake is a dune lake in the Northland Region of New Zealand. It is near the three Kai Iwi Lakes and close to the coast of the Tasman Sea, about 20 km south of Waipoua Forest.