Théols

The Théols is a 42.3 km river in central France. Its source is at 150 m near Bommiers, in the Boischaut natural region. It joins the Arnon near Lazenay.

Hydrology
The flow of the river was studied from 1971 to 1975 at Sainte-Lizaigne, located about 10 km from its confluence with the Arnon. At this point it drains 797 km², over 90% of its watershed. The river has an average flow of 2.99 m3/s at Sainte-Lizaigne.

There are seasonal fluctuations in the flow of the Théols, but they are not substantial. The highest flow rates are from February to May, with average flows from 3.5 to 5 m3/s (peak February–March). From April, the flow rate decreases regularly toward low water, which lasts from August to October. Floods are seldom important. The daily maximum flow recorded at Sainte-Lizaigne was 32.3 m3/s on March 22, 1974.

Its yearly drainage basin precipitation is currently 118 mm, just over a third of the national average of 320 mm, and also below the average of for the Loire basin (245 mm) and the Arnon (200 mm). The discharge was hence 3.75 L/s per km² of basin.

Fish
The river is rich in bleak, barbel, largemouth bass, cream, pike, crucian, roach, gudgeon, rudd, perch, tench, zander and catfish.