We have entered the world of consequences.
The United States Geological Survey just released a time lapse video that is jaw dropping. Local Juneau officials are being assisted by the USGS as rising water levels in the Mendenhall river rush towards the city. I hope people can evacuate if any possible danger exists. This glacial outburst occured within the last hour or so. This breaking story and video can be seen on USGS www.facebook.com/… .
The current high flows were brought about by the release of a glacial dammed lake on the nearby Mendenhall Glacier. A tributary glacier to the Mendenhall Glacier recently receded, leaving a new basin (Suicide basin) that fills up with melt water every summer.
The water level in the basin rose 100 feet since May 14, 2016 and began draining through the glacier on June 29, a process known as a glacial outburst flood. This new USGS monitoring station in the Suicide basin provided emergency officials with a 3-day warning on June 29th, before the flood peaked in downstream residential areas.
The USGS has operated streamflow information station on the Mendenhall River since 1965 (USGS Station Number 15052500). The outburst floods in 2011 (16,400 ft3/s) and 2014 (20,000 ft3/s) are the two highest annual peaks in the streamflow record. Prior to these outburst floods, the estimated 1-percent annual exceedance probability flow (100-year flood) for the Mendenhall River was 17,200 ft3/s. What was once a rare discharge on the Mendenhall is now a frequent event that floods homes and roads.
The Mendenhall River drains Mendenhall Lake, which is fed by the expansive Juneau Icefield. In addition to measuring the elevation of the water in the basin, the new monitoring station has a camera with a satellite modem.
WeatherChannel has a recent story that the lake began draining this afternoon local time.
JuneauEmpire one day ago.