Water Quality Study Conducted in Lake Sevan at 16 Monitoring Points

On July 28, a water quality study was conducted in Lake Sevan at 16 monitoring points, which include both the littoral and pelagic zones of the lake at various depths. This is reported by the Hydro-Meteorological and Monitoring Center.

The concentration of dissolved oxygen in the surface and middle layers of the lake is high, exceeding 6 mg/L, and is sufficient for the preservation of aquatic life. A decrease in oxygen concentration is observed in the Greater Sevan, mainly below 20 meters, and in the Lesser Sevan, starting from depths of 30 meters, decreasing to 0.8-2.3 mg/L in the bottom layers.

The water temperature in the littoral zones is quite high: 7.9-8.6°C in Greater Sevan and 4.5-7.6°C in Lesser Sevan. The lake's transparency ranges from 3 to 6 meters according to the Secchi disk. The water acidity in the littoral zone is between 7.6 and 8.7, while in the surface layer, it ranges from 8.3 to 9.0. Mineralization of water in the littoral zone is 500-530 mg/L, and in the surface layer, it is 487-497 mg/L.

Compared to last year, nutrient concentrations in the lake remain at a high level, which contributes to a fertile environment for blooming. The blooming process in the lake is still ongoing; however, its intensity is decreasing due in part to the absorption of nutrients. For instance, there is a sharp decrease in the concentrations of phosphate and nitrate ions in surface layers compared to July 15.

In Greater Sevan, the process of calcium release has started, which is clearly visible in satellite imagery.