Each summer in the mountains above Juneau, Alaska, meltwater from the massive Mendenhall Glacier flows into mountain lakes and into the Mendenhall River, which runs through town.

One of Alaska's most populated cities is bracing for potentially catastrophic flooding as a basin dammed within the Mendenhall Glacier has started to release water.

Alaska's capital of Juneau faced record floodwaters due to rainwater and snowmelt flowing downstream from a basin dammed by the Mendenhall Glacier.