Do lakes always have fresh water?

No, lakes do not always have fresh water. Some lakes contain saltwater, and these are known as salt lakes. Salt lakes are formed when water from a river or stream flows into a closed basin, meaning that there is no outlet for the water to escape. As the water evaporates, the dissolved salts become more concentrated, eventually forming a saltwater lake. Some of the most famous salt lakes in the world include the Great Salt Lake in Utah, USA, the Dead Sea in Israel, and the Salton Sea in California, USA.