|Water code||CH : 205|
|Drain over||Saane → Aare → Rhine → North Sea|
|origin||Confluence of the Ruisseau du Mormotey and Châ|
|muzzle||at Broc in the Saane
|Height difference||475 m|
|Bottom slope||29 ‰|
The Trême is a 16.3 kilometer long left tributary of the Saane (French Sarine ) in the canton of Friborg in Switzerland . It drains a section of the Freiburg Pre-Alps in the Gruyère region and belongs to the catchment area of the Rhine . The Trême was first mentioned in a document in 1478 as Tremaz and Treme . This name goes back to the Gallic word tragisama and means something like the very fast .
The headwaters of the Trême are located in the area between the Niremont in the west and the Moléson chain in the east on the parish of Semsales . The Ruisseau du Mormotey rises on the Alp Tremetta on the western slope of the Moléson, and flows northeast through a valley with the mountain forest Joux de Riaz . The Châ has its origin on the slope of the Niremont . At 1160 m above sea level M. these two source brooks unite, and the brook called Trême from now on flows to the north-northeast.
The Trême moves like a torrent in a densely wooded and deeply indented valley; smaller valley widenings are filled with gravel deposits. To the west of the city of Bulle , the Trême reaches the wide basin of the Gruyère region. At its exit from the mountains, the torrent has created an alluvial cone over time , on which large areas of Bulle and La Tour-de-Trême lie today .
Now the creek turns first to the east, later to the southeast, being flanked by the hills of the Bois de Bouleyres . In the alluvial plain north of the town of Gruyères , the Trême and the Albeuve (rises on the eastern slope of the Moléson) take up the largest side stream. At Broc the Trême flows at 685 m above sea level. M. in the Saane.
- Le Cha ( left source stream )
- Ruisseau du Mormotey ( right source stream )
- Riô des Vilieux ( right )
- Ruisseau de la Joux Noire ( left )
- Riô de la Mossetta ( right )
- Ruisseau du Pont-Courbe ( left )
- Riô du Chalet Neuf ( right )
- Ruisseau d'Inson ( left )
- Riô de la Cuva ( right )
- Ruisseau le Rio-Berthoud ( left )
- Canal des Usiniers ( right )
- Ruisseau du Botserin ( right )
- L'Albeuve ( left )
The course of the Trême stream is canalised, straightened and provided with stream barriers (thresholds) in the entire lower course from the entry into the Bulle basin. During floods, the Trême used to carry a large amount of debris with it and often overflowed its banks in the Bulle area. In contrast, the upper course is characterized by sections that are mostly left in their natural or near-natural state. However, there are also torrent barriers in various places to fix the valley floor and to contain the deep erosion and the scree. The Trême is characterized by a nivopluvial runoff regime .