The glacial flooding that sent residents of Alaska's capital city scrambling this week has become an annual ordeal for those who live along the picturesque river that winds from the nearby Mendenhall Glacier.

A "glacial outburst" threatens major flooding in Alaska's capital city as a glacial lake flood phenomenon inundates the Mendenhall River.

Alaska Gov. Mike Dunleavy declared a state disaster due to the "imminent threat of catastrophic flooding from a glacier lake outburst flood" in the Juneau area.

A historic flood is unfolding in Juneau, Alaska, as massive water releases from Suicide Basin threaten to break all previous records. With the Mendenhall River at risk of overflowing, officials have issued urgent evacuation notices and closed key city facilities.

The all clear has been given and residents have been allowed to return to their homes in Alaska’s capital of Juneau after a glacial lake outburst sent debris-filled water rushing down the Mendenhall River on Tuesday night and Wednesday morning.

Communities in Alaska have issued flood warnings and evacuations as the glacial release from Suicide Basin above Mendenhall Lake has begun.