Flood Warning

Mendenhall Lake gauge levels, along with USGS imagery from Suicide Basin and water levels within the basin, indicate that the basin is continuing its release of water into Mendenhall Lake and River. Levels on the Mendenhall Lake and River will rise through today as the release continues, with a forecast crest between 16.1 to 16.6 feet expected early Thursday morning.

* WHAT...Flooding caused by a glacier-dammed lake outburst continues.

* WHERE...The Mendenhall Lake And River near the Mendenhall Glacier Recreation area, View Drive and below Back Loop bridge.

* WHEN...Until 430 AM AKDT Friday.

* IMPACTS...Flooding of the area around Mendenhall Lake and along the Mendenhall River is imminent. Water levels will continue to rise through today while water temperatures will fall within the lake and river.

* ADDITIONAL DETAILS... - At 845 AM AKDT, gauge data reported a glacier-dammed lake outburst is ongoing. Flooding is expected to begin shortly near the Mendenhall Lake And River. - The outburst flood forecast is based on an estimated volume of water in the glacier dammed lake and an estimated release rate based on previous events. The extent of water drainage within the basin (partial or full) can vary widely between outburst flood events and is a major source of uncertainty in the forecast, particularly with regard to the peak flood stage. - For Mendenhall Lake : At 8:15am the stage was 5.6 feet and rising. Flood Stage is 9 feet. Forecast: A crest between 16.1 and 16.6 feet is expected around 5am and 9am Thursday. Water levels will go above minor flood state around 3pm Wednesday. Water levels will go above major flood stage around 1am Thursday.

Impacts: At 6.7 feet: Nugget Falls trail begins to flood near the "causeway" at the end of the trail.

At 7.7 feet: Nugget Falls trail begins to flood near the beginning of the trail. Along the Mendenhall River some sections will experience bank erosion resulting in dangerous tree fall. These conditions could make floating the river more hazardous with the higher water levels.

At 9 feet: Water starts to cover Skaters Cabin Road between Skaters Cabin and West Glacier Trailhead, also water will flow into the Mendenhall Lake Campground.

At 10 feet: Water levels will inundate Mendenhall Campground with up to 3 feet of water covering low areas as well as up to 1.5 feet of water covering Skaters Cabin Road. Portions of West Glacier Trail will be impassable. Areas along View Dr will start to flood and cause minor flooding of yards. Closure of pedestrian pathways beneath Brotherhood Bridge and the trail system on the west side of Mendenhall River during outburst events.

At 11 feet: Some homes along View Dr will have up to 1.5 feet of water in yards. Locations below back loop bridge will see bank erosion along unreinforced river banks along with hazardous navigation from debris in the river. Homes along the river on Meander Way will begin to see flooding of some backyards on the outside of the HESCO levee. Portions of the Dredge Lake Trail System will be impassable. Flood waters start to reach Dredge Lake.

At 12 feet: Significant bank erosion along unreinforced river banks. The low section of road past 9374 View Dr will be flooded with up to 0.5 feet of water. Some houses on the south side and the east end of View Dr will start to flood. Water begins to flood some backyards of homes on the northside of View Dr as well as other low lying areas. Back Loop Rd Bridge will be closed during outburst events.

At 13 feet: The low section of road past 9374 View Dr will be flooded with 2 ft of water. Water begins to flow through some backyards of homes on the northside of View Dr and flood low lying areas. A few locations on View Dr will see depths of 1 to 2 feet of water in homes.

At 14 feet: The low section of road past 9374 View Dr will be significantly flooded and impassable. Water will begin to flow over the road from water flowing behind homes on the north side of View Dr. More homes along View Dr will begin to see moderate to major flooding. Locations on River Rd with low river banks will begin to see water approach driveways.

At 15 feet: Major flooding of multiple homes along View Dr. Water will begin to approach a few homes along River Rd with low river banks with possible flooding of driveways and 1 to 2 feet of water in backyards. Up to 1 foot of water covering Riverside Dr at Tournure St and Mendenhall River School.

At 16 feet: Water starts to overtop the bank and flood low lying areas near Wildmeadow Ln. Up to 0.5 feet of water will be in the intersection of Skaters Cabin Rd and Arctic Cir. Some backyards of homes between Tamarack Ct and Whitewater Ct will start to see flood waters along with water approaching River Rd near homes with low river banks and possibly flooding those homes. Water will start to flood backyards of homes on Meadow Ln and Stikine St.

At 17 feet: This is an estimate that water will be overtopping the river banks and flooding into the homes around Wildmeadow Ln. Businesses in the Vintage Park Blvd area will be surrounded and potentially inundated by flood waters. Homes on Meadow Ln from Stikine St to Eagle St will be inundated with flood water. Water will be covering Tournure St from Riverside Dr to Columbia Blvd. Black Wolf Way and Pond Vista Dr will have water across the roads. All parts of View Dr will be covered by flood water.