Tinnelva

{{short description|River in Telemark, Norway}}

{{Use dmy dates|date=May 2024}}

{{Infobox river

|name = Tinnelva

|native_name =

|native_name_lang =

|name_other = Tinne / Tinnåa

|etymology =

|image = Notodden Tinnelva.jpeg

|image_size =

|image_caption = Tinnelva and Tinnsjå

|image_alt =

|map =

|map_size =

|map_caption =

|map_alt =

|pushpin_map = Telemark#Norway

|pushpin_map_caption = Location of the river

|subdivision_type1 = Country

|subdivision_name1 = Norway

|subdivision_type2 = County

|subdivision_name2 = Telemark

|subdivision_type3 = Municipalities

|subdivision_name3 = Notodden Municipality

|length = {{convert|29|km|mi|abbr=on}}

|width_min =

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|source1 = Tinnsjå lake

|source1_location = Tinnoset, Telemark

|source1_coordinates = {{coord|59.72428061|9.0234661|region:NO}}

|source1_elevation = {{convert|192|m}}

|mouth = Heddalsvatnet lake

|mouth_location = Notodden, Telemark

|mouth_coordinates = {{coord|59.557113|9.2479133|display=inline,title}}

|mouth_elevation = {{convert|16|m}}

|progression =

|river_system = Skien watershed

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Tinnelva (also known as Tinne or Tinnåa) is a river in Notodden Municipality in Telemark county, Norway. The {{convert|29|km|adj=on}} long river flows between two lakes: Tinnsjå and Heddalsvatnet. The river begins at the village of Tinnoset draining from the lake Tinnsjå. It flows to the south and east, past the village of Gransherad and the Gransherad Church, past the Lisleherad Church further downstream, and finally emptying into the lake Heddalsvatnet at the town of Notodden.{{Cite encyclopedia |title=Tinne |encyclopedia=Store norske leksikon |publisher=Kunnskapsforlaget |url=https://snl.no/Tinne |date=2023-05-24 |editor-last=Lundbo |editor-first=Sten |language=no |accessdate=2023-08-27}}{{Cite web |title=Tinne (elv), 3808 Notodden |url=https://temakart.nve.no/tema/elvenett |access-date=2023-08-27 |publisher=Norwegian Water Resources and Energy Directorate |language=no}}

There are several waterfalls along the river: Årlifossene, Grønvollfoss, Svelgfoss and Tinnfoss. These waterfalls are exploited for hydroelectric power generation since the river drops about {{convert|138|m}} over these four waterfalls. The hydroelectric power stations along the river have a combined installed capacity of {{convert|182|MW|lk=on}}.