Second release from Suicide Basin this year underway; peak river level of about 10 ft. forecast

Crest expected Friday morning, according to National Weather Service; basin on Wednesday was 1,189 feet, well below 1,347-foot overtopping level

A graph shows the predicted level of the Mendenhall River during a release from Suicide Basin expected to crest on Friday, Oct. 2, 2026. (National Weather Service Juneau)

By Mark Sabbatini

Juneau Independent

A second release from Suicide Basin this year is expected to peak Friday morning at about 10 feet, well below the 14.7 feet of the glacial lake outburst flood in August, according to the National Weather Service Juneau.

"We're pretty confident there's a release for two reasons: The water temperature in the lake has plummeted and that's a pretty good indication that cold water from the basin is impacting Mendenhall Lake," Andrew Park, a Juneau meteorologist, said in an interview at about 7:15 a.m. Thursday. Also, the water level in the lake is rising measurably.

An update at 2:30 p.m. on Suicide Basin’s official monitoring website states, "The current forecast indicates Mendenhall Lake will crest near 9.8 to 10.3 ft sometime between 5 am and 9 am Friday, October 2nd."

A river level of 10 feet is considered moderate flood stage. Impacts include up to three feet of water at Mendenhall Campground, 1.5 feet of water on Skaters Cabin Road, some flooding of the View Drive area and closure of pedestrian paths near the Mendenhall River, according to NWSJ.

The City and Borough of Juneau, in an announcement on its website Thursday, stated, "Out of an abundance of caution, and to continue improving flood response procedures, CBJ is deploying a limited number of response personnel and equipment, including pumps, to areas of known seepage. However, no impacts to residential areas are currently expected."

The Suicide Basin website notes secondary releases from the basin after major floods in August have occurred during the past two years. A 2024 release between Oct. 19 and 21 saw the Mendenhall River crest at 10.77 feet, a 2025 release between Sept. 14 and 16 saw a crest of 9.63 feet.

Changes at Suicide Basin and Mendenhall Lake were observed beginning Wednesday, which was also the last of three days of scheduled presentations to the U.S. Army Corps of Engineers by entities interested in designing and building a long-term flood solution. The Army Corps has stated a preferred bidder is expected to be selected Oct. 7.

• Contact Mark Sabbatini at editor@juneauindependent.com or (907) 957-2306.