Japana Lake

Japana Lake (ჯაპანის ტბა) is a notable freshwater lake in western Georgia’s Guria region, located within the Lanchkhuti Municipality near the village of the same name. Situated in the Kolkheti Lowland at a low elevation, it holds the distinction of being Georgia’s largest oxbow lake – a crescent-shaped lake formed when a meander (a winding curve) of a river is cut off from the main channel. In this case, it was formed by changes in the course of the Rioni River, hence it’s sometimes locally referred to as “Narionali Lake”. Fed by rain and groundwater, this shallow lake serves as an important local ecosystem. It’s known to support various fish species and was historically used for fish farming during the Soviet era. Additionally, Japana Lake provides habitat for numerous wild ducks and other migratory birds, especially during winter. While primarily significant locally, particularly for fishing, it represents an interesting example of river geomorphology and a typical Kolkheti Lowland wetland environment.

Identification and Location

• Name: Japana Lake (ჯაპანის ტბა). Also known locally as Narionali Lake.
• Location:
  • Country: Georgia
  • Region: Guria
  • Municipality: Lanchkhuti Municipality
  • Nearest Landmark: Village of Japana. Located within the Kolkheti (Guria) Lowland. Nearby are two smaller lakes, Didi (Big) Narionali and Mtsire (Small) Narionali.
  • Coordinates: Approximately 42°05′ N latitude, 42°12′ E longitude.
  • Relationship to other bodies of water: An oxbow lake, formed from a former meander of the Rioni River. It’s now largely endorheic (lacking a significant surface outlet) but exists within the broader Kolkheti Lowland drainage system influenced by the Rioni.

Physical Characteristics

• Surface Area: Approximately 1.17 square kilometers (about 0.45 square miles).
• Maximum Depth: Specific maximum depth figures vary, but sources suggest it’s relatively shallow.
• Average Depth: Approximately 3.7 meters (about 12 feet).
• Volume: Estimated at around 4.3 million cubic meters.
• Elevation: Low elevation, about 13 meters (approx. 43 feet) above sea level.
• Shoreline Length: Dependent on the lake’s specific oxbow shape.
• Water Source(s): Primarily atmospheric precipitation and groundwater. Historically may have received water diverted from the Rioni or Kheviskali rivers for fish farming.
• Outlet(s): Generally considered endorheic (closed basin) or having very limited outflow.
• Water Type: Freshwater.
• Basin Geology: Fluvial origin (oxbow lake formed by river channel changes) within the alluvial deposits of the Kolkheti Lowland.

Ecological Information

• Flora (Plant Life): Surrounded by greenery; likely features typical wetland and aquatic vegetation along its shores and in shallower areas, such as reeds and various submerged or floating plants.
• Fauna (Animal Life): Used for fish farming (pisciculture), indicating it supports fish. Species mentioned include Hypophthalmichthys (Silver Carp), Carp, Pike, and Idella (Grass Carp), Crucian Carp, and Shamaya. Attracts numerous migratory birds during winter, particularly hundreds of wild ducks and other waterfowl. Also habitat for typical local amphibians and reptiles.
• Trophic Level: Likely Mesotrophic to Eutrophic, influenced by its lowland setting, potentially past fish farming activities, and nutrient inputs.
• Water Clarity: Likely moderate to low.
• Water Temperature: Follows the mild Guria climate, warming in summer, unlikely to freeze deeply or for prolonged periods.
• pH Levels & Dissolved Oxygen Levels: Specific data not readily available.
• Unique Ecological Features: Largest oxbow lake in Georgia. Important wintering site for local wild duck populations.
• Conservation Status: No major specific conservation designation is widely reported.
• Invasive Species: Fish species like Silver Carp and Grass Carp may have been introduced for aquaculture.

Human Interaction and Significance

• Historical Significance: Associated with the village of Japana. Historically significant as the site of a large Soviet-era fish farm (reportedly 140 hectares, producing 70-80 tons of fish annually).
• Current Uses: Currently used for raising fish (fish farming/impoundment). Popular spot for local recreational fishing. Potential for birdwatching, especially in winter.
• Environmental Issues: Potential impacts from past and present aquaculture activities (nutrient loading, introduction of non-native species). Possible effects of agricultural runoff from surrounding areas. Water quality management is relevant due to fish farming.
• Management and Conservation Efforts: Management likely related to its use as a fish farm/impoundment and general municipal environmental oversight.
• Local Communities: Important economic resource related to fish farming (historically and potentially currently). Valued local spot for recreation (fishing).

Interesting or Unique Facts

• Georgia’s largest oxbow lake, formed from a cutoff meander of the Rioni River.
• Named after the nearby village of Japana.
• Known locally also as Narionali Lake.
• Serves as a winter habitat for hundreds of wild ducks.
• Has a history of significant fish farming activity.