Orklaelva

Orkla
Mouth of the river at Orkanger
Country	Norway
Basin features
Main source	Orkelsjøen 1,058 m (3,471 ft)  above sea level
River mouth	Trondheim Fjord 0 m (0 ft)
River system	Orkla
Basin size	3,053 km2 (1,179 sq mi)
Tributaries	Left: Inna, Byna, Grana, and Resa Right: Ya and Svorka
Physical characteristics
Length	179 km (111 mi)

The Orkla is the longest river in Sør-Trøndelag county, Norway. The 179-kilometre (111 mi) long river follows the Orkdalen valley, discharging into the Orkdalsfjord, an arm of Trondheim Fjord, at the village of Orkanger.

The river originates in the lake Orkelsjøen in the municipality of Oppdal. The river runs through the municipalities of Oppdal, Tynset, Rennebu, Meldal, and Orkdal. The municipalities are all in Sør-Trøndelag county, except for Tynset which is in Hedmark county. Major villages along the river include: Orkanger, Fannrem, Vormstad, Svorkmo (in Orkdal); Storås, Meldal, Å (in Meldal); and Rennebu and Berkåk (in Rennebu).

The Orkla is a popular river for salmon fishing, a famous fisherman there being former Liverpool player Vegard Heggem. About an 88-kilometre (55 mi) long stretch of the river through Orkdal, Meldal, and Rennebu is used for salmon fishing throughout the season from June through August.

The river is regulated by five power generation reservoirs, which were built between 1978 and 1985. The reservoirs have been a successful method of flood control preventing the river's major seasonal flooding.

The Old Norse form of the name was just Ork (still found in the names Orkanger, Orkdal and Orkland). The meaning of the name is unknown (maybe derived from the verb orka which means "to work" - the meaning of the name would then be "the river that works its way forward"). The name Orkla (with the diminutive ending -la) originally belonged to the uppermost part of the river (lying in Tynset, Hedmark), and the meaning of this name is probably "the small part of Ork".