The Kovzha (Ковжа) is a river in the Vytegorsky, Belozersky, and Vashkinsky districts of Vologda Oblast in Russia. It originates from Lake Kovzhskoye and is a tributary of Lake Beloye. It is 86 kilometres (53 mi) long, and the area of its basin 5,000 square kilometres (1,900 sq mi). The Kovzha River is a part of the Volga–Baltic Waterway. The main tributaries are the Tumba and the Shola.