Kumisi Lake is an artificial lake in eastern Georgia, in Kvemo Kartli, southeast of the village of Kumisi. The Kumisi hollow is filled with Quaternary lacustrine-fluvial and colluvial-proluvial deposits. As late as the 1960s the lake's area was a mere 0.48 km² and its depth reached 50 cm. The lake's enlargement was brought about artificially. The rise in water level and depth was followed by an increase in fish. Before the lake was enlarged its water was bitterly salty (a factor unfavorable to fish life); this water was then drained from the lake and replaced with water from the Mtkvari River, which raised the level, multiplied the fish fauna and made the water relatively fresher. The lake's water level fluctuates greatly.