Glacial rivers are watercourses formed by the melting of glaciers. As glaciers move, they carve out valleys and transport sediment, which contributes to the river's unique characteristics. These rivers often have a milky appearance due to the fine particles of rock flour suspended in the water. Typically found in mountainous regions, glacial rivers can change rapidly with seasonal melt. They are usually cold and can flow with great force, especially during warmer months when melting accelerates. The water in these rivers is often rich in minerals, making them important for ecosystems and local wildlife, including species like salmon.