Orne (river)

The Orne () is a river in Normandy, within northwestern France. It is long. It discharges into the English Channel at the port of Ouistreham. Its source is in Aunou-sur-Orne, east of Sées. Its main tributaries are the Odon and the Rouvre.
The Orne flows through the following departments and towns:
Name.
The name of the Orne in Normandy, which is referred to as the "Olinas" by Ptolemy, is a homonym of Fluvius Olne, the Orne saosnoise in Sarthe, which Xavier Delamarre traces back to the Celtic olīnā (elbow).
Hydrology and water quality.
The waters of the Orne are typically moderately turbid and brown in colour. pH levels of the Orne have been measured at 8.5 at the town of St. Andre sur Orne where summer water temperatures approximate 18 degrees Celsius. Electrical conductivity of the Orne has been measured at 30 micro-Siemens per centimeter.