Fensch
The Fensch or Fentsch is a river in the Moselle department of the Grand Est region of France. It is a left tributary of the Moselle, and thus a sub-tributary of the Rhine.
Geography
The Fensch is long.It rises in Fontoy in the west of the Moselle department.
It then crosses Knutange, Nilvange, Hayange, Serémange-Erzange and Florange before discharging from the left into the Moselle between Metz and Thionville on the border of the commune of Illange.
It generally flows from west to east.
Originally, as shown by the Cassini map, the waters of the lower part of the Fensch combined with the waters of the Veymerange and fed the moat around the town of Thionville before joining the Moselle. After the removal of the fortifications, the Fensch was diverted to its current course to supply water to the new ironworks installed a little south of this locality.
The springs of Morlange and of Ranguevaux were captured in 1886 and carried by gravity to Thionville by a long conduit.
Names
- Feuschen, Fensth, Flensch, Fenche, Feusche
- In German: ''Fentsch''
Communes and cantons crossed
Tributaries
The river has four tributaries:- The petite Fensch
- The Krisbach or Krebsbach long in the three communes of Ranguevaux, Fameck and Florange.
- The Algrange and Marspich streams
- The canalized Moselle
Hydrology
The Fensch has very moderate seasonal fluctuations of flow, which is rarely the case in northern Lorraine. High water events occur in winter and are characterized by average monthly flows in the range of from December to April inclusive. Beginning in April, the flow gradually decreases to the low summer-fall waters that occur from July to October. The average monthly flow decreases to a consistent flow of about in September. The fluctuations are more pronounced over short periods or between years.
At low water level, the 3 consecutive-day minimum flow can drop to during a five-year dry period, which is far from severe. Floods are moderately important, given the small size of its watershed. They are proportionally more or less half as large as those of its neighbor, the Orne. The 2-year and 5-year peak instantaneous flows are and. The 10-year peak flow is, the 20-year peak flow is and the 50-year peak flow is. The highest instantaneous flow recorded at Florange was on 12 April 1983, with an average flow of that day. This flood was of a two-year order, and therefore not at all exceptional.
Overall, the Fensch is a very abundant river, more than most rivers of the Moselle basin, particularly those of the Moselle department. Annual rainfall in its basin is, which is more than twice that of France as a whole and well above the average of the French part of the Moselle basin, which is per year. The river's flow reaches per of the basin.