| Someș/Szamos | |
| Map: | Raul Somes.png |
| Source1 Location: | Confluence of Someșul Mare and Someșul Mic |
| Source1 Coordinates: | 47.1447°N 23.9133°W |
| Mouth Location: | Tisza |
| Subdivision Type1: | Countries |
| Subdivision Name1: | Romania and Hungary |
| Subdivision Type2: | Cities |
| Name Etymology: | According to one view: borrowed Hungarian (Szamos, archaically Zomus), perhaps directly from Slavic, from latin. The Hungarian name formed with Slavic mediation. In Roman times, the river was known as Samum (accusative). Its root may be in connection with the French river name Somme. A proposed Indo-European root, *s(w)om-isyo ('rich in catfish') is unlikely.[1] The opposite view starts from the radical çam-, through Latin Samus, and by late substrate transition of stressed a to stressed o (like in Potaissa/Patavissa).[2] |
| Length: | 415km (258miles) |
| Mouth Elevation: | 122m (400feet) |
| Mouth Coordinates: | 48.114°N 22.3394°W |
| Discharge1 Avg: | 130m3/s138.593m3/s[3] |
| Basin Size: | 18146km219108.8km2[4] |
| Tributaries Left: | Someșul Mic, Sălaj |
| Tributaries Right: | Someșul Mare, Lăpuș |
| Waterbodies: | 7[5] |
| Discharge1 Location: | Vásárosnamény, Hungary (near mouth) |
The Someș (in Romanian; Moldavian; Moldovan pronounced as /ˈsomeʃ/) or Szamos (German: Somesch or Samosch) is a left tributary of the Tisza in Hungary and Romania. It has a length of 415km (258miles) (including its source river Someșul Mare), of which 50 km are in Hungary.[6] The Someș is the fifth largest river by length and volume in Romania.[7] The hydrographic basin forms by the confluence at Mica, a commune about 4 km upstream of Dej, of Someșul Mare and Someșul Mic rivers. Someșul Mic (formed by the confluence of Someșul Rece with Someșul Cald) originates in the Apuseni Mountains, and Someșul Mare springs from the Rodna Mountains.[8]
Someșul Mare has a length of 130 km and an area of 5,033 km2 and a slight asymmetry in favor of the left side of the basin.[9] For the entire basin of Someș, the asymmetry on left becomes pronounced between Dej and Ardusat to change in the opposite direction after receiving the Lăpuș on the right side. The valley of Someșul Mare has much auriferous alluvium that, until the early 20th century, were brought to the surface using traditional tools. Specialists say that in the Someșul Mare were found grains of gold of 21 carats.[10]
The Someș drains a basin of 18146km2,[6] of which 15740km2 in Romania.[11] Its basin comprises 403 rivers with a total length of 5,528 km, or 7% of the total length of the country. Basin area represents 6.6% of the country area and 71% of the area of Someș–Tisza hydrographic basin.
To prevent flooding, the Someș is dammed in the lower course. In the spring of 1970, due to heavy rains, the Someș flooded part of Satu Mare and surrounding plains. The discharge exceeded 3,300 m3/s compared to that year's average of 210 m3/s.[12]
The following rivers are tributaries to the river Someș: