| Tartarchay | |
| Name Other: | Tartar, Թարթառ |
| Subdivision Type1: | Country |
| Subdivision Name1: | Azerbaijan Partly: Republic of Artsakh (de facto) |
| Subdivision Type3: | Region |
| Subdivision Name3: | Caucasus |
| Subdivision Type4: | Districts |
| Subdivision Name4: | Kalbajar, Barda, Tartar Partly: Martakert Province (de facto) |
| Subdivision Type5: | Cities |
| Subdivision Name5: | Kalbajar, Martakert, Tartar, Barda |
| Length: | 184km (114miles) |
| Discharge1 Location: | directly downstream into Kura |
| Discharge1 Avg: | 22m3/s |
| Source1: | Lesser Caucasus |
| Source1 Location: | Near Istisu, Kalbajar District, Azerbaijan |
| Source1 Coordinates: | 39.9322°N 45.9683°W |
| Source1 Elevation: | 3120m (10,240feet)[1] |
| Mouth: | Kura |
| Mouth Location: | Barda, Azerbaijan |
| Mouth Coordinates: | 40.4469°N 47.3072°W |
| Basin Size: | 2650km2 |
| Tributaries Left: | Levçay, Ağdabançay |
| Tributaries Right: | Turağayçay |
The Tartar (Azerbaijani: Tərtərçay, Armenian: Թարթառ) is one of the tributaries of the Kura river located in Azerbaijan. It passes through the districts of Kalbajar, Barda and Tartar.
The Tartar is a left tributary of the Kura, the largest river in the Caucasus. The river originates in the area where Qonqur, Alaköz and Mıxtökən mountain ranges meet on the Karabakh Plateau in the vicinity of the hot springs village of Istisu located in Kalbajar Rayon of Azerbaijan.[2] The altitude where the river originates from mountain springs is 3120m (10,240feet) above sea level. The river flows eastward through the whole Kalbajar Rayon (de facto Martakert Province) passing through Kalbajar city, Tartar and Barda raions and through Tartar and Barda cities before discharging into the Kura. The river has two left tributaries: the Levçay (36km (22miles)) and the Ağdabançay (19km (12miles)), and one right tributary, the Turağayçay (35km (22miles)). Sarsang reservoir was built on Tartar river in 1976 for electricity generation and irrigation purposes.[1]
The river is 184km (114miles) long, and has a drainage basin of 2650km2.[3] Tartarchay is considered one of the water-rich tributaries of Kura within Azerbaijani territory. The water volumes are sourced from rainfall (14%), snow (28%) and underground waters (58%). During spring and summer months, the snow melting in the mountains causes floods, making up 65–70% of the annual water flow. In August and September, the water levels decrease. From October until November, the rainfall increases the water levels again. The average annual discharge of the river is 22m3/s. Average annual flow is 693.8 million m3. The average mineralization of the river is 300–500 mg/L with hydrocarbons and calcium.[1]
What was once the famous resort village of Istisu (in Azerbaijani), which was occupied and ruined following the First Nagorno-Karabakh War, is located on the lower part of the river. The resort contains both natural drinking mineral water and hot water spring for bathing. Sarsang Hydro Power Plant with capacity of 50 megawatts is operated at the Sarsang reservoir of the river[4] and is the main source of electric energy for the Republic of Artsakh (40–60%).[5]