Suran (river)

The Suran , is a French river which runs in the departments of the the Jura and of the Ain. It is an affluent of the Ain out of Right Bank.

Geography

Suran is born in the small town from Loisia, in the department of the the Jura. It moves from the start towards the south, direction which it will maintain to its confluence with Ain on the level of the locality of Bridge-in Ain.

Hydrology

Suran is a rather abundant river, like all the rivers resulting from the southern part of the area of the Massif of the Jura. Its flow was observed over one 39 years period (1969-2007), with Bridge-in Ain, locality of the Département of Ain located at the level of its confluence with the Ain. The catchment area of the river is there of 349 km ² (either the entirety of the basin).

Interannual medium flow or module of the river with Bridge-in Ain east of 6,71 m ³ a second.

Suran present of the seasonal fluctuations of flow very marked, as very often in the east of France, with high waters of winter carrying the average monthly flow on a level located between 8,0 and 11,3 m ³ a second, from November to April included (with an in February maximum), and low waters of summer, at the end of June at the end of September, with a fall of the monthly medium flow up to 1,04 m ³ in August. But the fluctuations are much more marked over moreover short periods.

With the low water level, the VCN3 can fall until 0,026 m ³, in the event of dry period quinquennial, that is to say hardly 26 liters a second, which is extremely low, but normal in the areas of Jurassic Piedmont. Let us recall that the VCN3 is the past minimal quantity or minimal flow over three days consecutive.

As for the risings, they have their importance, while remaining moderate compared with the average of the rivers of the southern half of France. The QIX 2, or calculated flow of biennial rising, and QIX 5 are worth respectively 85 and 110 m ³. The QIX 10 or calculated flow of decennial rising is of 130 m ³ a second, the QIX 20 of 150 m ³ and the QIX 50 of 170 m ³. (see note).

To have an idea of the importance of these flows of rising, one can compare them with one affluents of the Marne in the east of Paris, the Grand Morin, famous for his overflows. The QIX 10 of Large Morin at the end of the course is worth 140 m ³ (against 130 for Suran) and its QIX 50 is assembled to 200 m ³ (against 170 for Suran). Thus in spite of a basin more than three times less extended and a medium flow of about half, the volume of believed of Suran is equivalent almost those of Large Morin.

The maximum instantaneous flow recorded with Bridge-in Ain was of 168 m ³ a second on April 18th, 2005, while the value maximum day laborer was of 125 m ³ a second the same day. By comparing the first of these figures on a QIX scale of Suran, it arises that the risings of April 2005 were of order cinquantennal, and thus rather exceptional.

Suran is an abundant river, supplied with such abundant precipitations they, in the area of the solid mass of the Jura and of its Piedmont. The Lame of water past in its catchment area is of 608 millimetres annually, which is high, definitely higher than the average overall of France, but a little lower than the average of the totality of the basin the Rhone (670 millimetres with Valence), and much lower than the water blade of Ain than Bridge-in Ain (1 201 millimetres). The specific Flow of the river (or Qsp) thus reached 19,2 liters a second and per square kilometer of basin.

References

Random links: