Oum Er-Rbia (Arabic: أم الربيع, romanized: the mother of spring) is a large, long and high-throughput river in central Morocco.

The river is 555 kilometres (345 mi) long. With an average water throughput of 105 m/s, Oum Er-Rbia is the second-largest river in Morocco after the Sebou River. It originates in the Middle Atlas and passes through the city of Khénifra, arriving at its mouth at the Atlantic Ocean at the port of Azemmour, located on its left bank. Oum Er-Rbia has six dams, the most important of which is Al Massira Dam. Its most important tributaries are El-Abid River, Tessaoute River, and Lakhdar River.

According to scholars, the original Berber common name of the river is Wansifen and was only changed recently, circa 16th or 17th century, and a nearby village called Oum Rabia might have influenced this change.

Oum Er-Rbia is fed by a large number of groundwater springs. The area near its headwaters is called "The Forty Springs" as a result, although that is a poetic term rather than an exact count.

Gallery

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  This cascade forms one of the sources of the Oum Er-Rbia, near Khénifra
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  Structures along the Oum Er-Rbia
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  Azemmour from the Oum Er-Rbia
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  The Oum Er-Rbia river