Heddalsvatnet () is a

lake A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from ...

in Notodden Municipality and

Midt-Telemark Municipality Midt-Telemark is a List of municipalities of Norway, municipality in Telemark county, Norway. It is located in the Traditional districts of Norway, traditional district of Midt-Telemark. The administrative centre of the municipality is the villag ...

Telemark Telemark () is a Counties of Norway, county and a current electoral district in Norway. Telemark borders the counties of Vestfold, Buskerud, Vestland, Rogaland and Agder. In 2020, Telemark merged with the county of Vestfold to form the county o ...

county,

Norway Norway, officially the Kingdom of Norway, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. The remote Arctic island of Jan Mayen and the archipelago of Svalbard also form part of the Kingdom of ...

. The lake is located just south of the town of Notodden. The village of Heddal and the Heddalen valley are located to the northwest of the lake.

Geography

The main rivers that flow into the lake are the rivers Tinnelva and Heddøla. The

catchment basin A drainage basin is an area of land in which all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, th ...

covers a total area of . The southern part of the lake is called Bråfjorden and is separated from the northern part by the Nautsundet strait which is crossed by the county road 360 bridge. The railway line to Notodden (the Bratsberg Line) runs along the eastern shore. The villages of Heddal and Yli lie along the northwestern short of the lake and the villages of Hjuksebø and Hjuksevelta lie along the eastern shore of the lake. The lake is part of the Skien watershed and is connected to the ocean by the Telemark Canal. Heddalsvatnet is only above sea level and only two locks at

Skien Skien () is a municipality in Telemark county, Norway. It is located in the traditional district of Grenland, although historically it belonged to Grenmar/Skiensfjorden, while Grenland referred the Norsjø area and Bø. The administrative ...

were needed to allow ships to sail on the lake. The canal opened in 1861 and made Notodden into Norway's largest fresh water port. In the late 1800s, seafaring vessels were constructed at the shores of Heddalsvatnet.

History

Neolithic The Neolithic or New Stone Age (from Ancient Greek, Greek 'new' and 'stone') is an archaeological period, the final division of the Stone Age in Mesopotamia, Asia, Europe and Africa (c. 10,000 BCE to c. 2,000 BCE). It saw the Neolithic Revo ...

times, after the ice age, the ocean was about higher in this area. Heddalsvatnet was a saltwater fjord connected to the ocean. The ocean stretched inland like a

fjord In physical geography, a fjord (also spelled fiord in New Zealand English; ) is a long, narrow sea inlet with steep sides or cliffs, created by a glacier. Fjords exist on the coasts of Antarctica, the Arctic, and surrounding landmasses of the n ...

past Heddalsvatnet, all the way to Hjartdal. The first humans in central Telemark presumably travelled by boat deep inland along the fjords that are now gone.

Post-glacial rebound Post-glacial rebound (also called isostatic rebound or crustal rebound) is the rise of land masses after the removal of the huge weight of ice sheets during the last glacial period, which had caused isostatic depression. Post-glacial rebound an ...

eventually separated Heddalsvatnet from the ocean and turned it into a freshwater lake. As the ocean levels decreased, the lake became separated from the ocean around 1500 BC. The water in the lake gradually became

freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mi ...

around the

Bronze Age The Bronze Age () was a historical period characterised principally by the use of bronze tools and the development of complex urban societies, as well as the adoption of writing in some areas. The Bronze Age is the middle principal period of ...

, according to archaeologist Pål Nymoen.

References

{{reflist Lakes of Telemark Notodden