EVALUATION OF WATER QUALITY AND TROPHIC CONDITION OF YUVACIK (KOCAELI-TURKEY) DRINKING WATER DAM RESERVOIR

This study was conducted in order to examine some physico-chemical properties and determine the trophic status of Yuvacık Dam Lake, which is located within the provincial borders of Kocaeli, to reveal the surface water quality and pollution problems. Raw water samples were taken from 5 different stations at different depths for two periods (September 2016 and May 2017). As a result of the research, it was found that the average values of water quality parameters of Yuvacık Dam Lake are in the range of water quality class I (high quality, very good) - II (slightly polluted, good) according to the quality criteria. According to the eutrophication criteria, the trophic level of the lake was mesotrophic in terms of total nitrogen (TN) and total phosphorus (TP) concentration, oligotrophic in terms of chlorophyll-a, and periodically mesotrophic in terms of light transmittance. The mean Trophic State Index (TSI) value was calculated as 44.1 and it was determined that the trophic level of the lake was mesotrophic.