Lake Kyoga (also spelled Kioga) is a large shallow lake of Uganda, about 1,720 km2 (660 sq mi) in area and at an elevation of 1034 metres. The Victoria Nile flows through the lake on its way from Lake Victoria to Lake Albert. The main inflow from Lake Victoria is regulated by the Nalubaale Power Station in Jinja. Another source of water is the Mount Elgon region on the border between Uganda and Kenya. While Lake Kyoga is part of the Great Lakes system, it is not itself considered a great lake.
The lake reaches a depth of about 5.7 metres, and most of it is less than 4 metres deep. Areas that are less than 3 metres deep are completely covered by water lilies, while much of the swampy shoreline is covered with papyrus and water hyacinth. The papyrus also forms floating islands that drift between a number of small permanent islands. Extensive wetlands fed by a complex system of streams and rivers surround the lakes. Nearby Lake Kwania is a smaller lake but deeper.
Forty-six species of fish have been found in Lake Kyoga, and crocodiles are numerous.
Excessive El Niño rains in 1997-1998 resulted in exceptionally high water levels, causing large islands of papyrus and water hyacinth mats to become dislodged on the lake and to accumulate at the lake's outlet into the Victoria Nile. This blockage caused the water level to become even higher, flooding about 580 square kilometres of the surrounding land (DWD 2002) and resulting in population displacement and severe socioeconomic damage. In 2004, the Egyptian government granted Uganda a gift of 13 million USD to streamline the flow of the Nile at Lake Kyoga. As of 2005, the outlet was still largely blocked.