Glacial meltwater plays an important role in the landscapes around glaciers, and in some cases in the lives of the people who live near them. For example, in Switzerland, up to 15 metres of ice may melt vertically from the lower lying parts of the Grosser Aletschgletscher every summer and help generate the hydroelectric power used by the totally electrified Swiss railway system. In the arid regions of northwestern China and in Argentina glacial meltwater irrigates desert land, ensuring the survival of many thousands of people. In the Cordillera Blanca of Peru, complex irrigation networks connected to glacial meltwater streams supply varied crops on steep mountainsides during the dry season. Major cities, such as Lima and La Paz, rely heavily on glacial meltwater for sustaining millions of people.

Meltwater also plays a significant part in the development of glacial landscapes. In high polar regions, during the short summer season, snow and ice melt combine with rainwater to provide a noisy, tinkling, gurgling, rushing or roaring background to any activity near glaciers. Glaciers everywhere generate their own stream systems, either on their surface or within and below the ice, in a similar manner to streams in limestone regions. During the peak period of melting in early summer the stream that emerges at the snout of a glacier is often a spectacular torrent, frequently flooding the valley floor below.