JUNEAU, Alaska — In her yard under the blazing sun Wednesday, Debbie Penrose Fischer leafed through a water-logged cookbook with sentimental value that she hoped to salvage but doubted she could. Nearby, friends helped carry boxes out of her family's garage, which was inundated this week after a lake dammed by the Mendenhall Glacier let rip — sending floodwaters into neighborhoods like hers that never had to worry about that threat before.
''We're blessed,'' she said. ''Nobody was hurt. Lots of things I love are gone, and I don't like that. But it's just stuff, you know?''
About 100 homes and some businesses were damaged by rapidly rising floodwaters that crested around 3:15 a.m. Tuesday, according to initial estimates. In some areas, cars floated as people scrambled to evacuate. Fischer's daughter, Alyssa, who lives across the street, said the water in the road at one point reached her hips.
The waters began receding Tuesday, and water levels had returned to the normal range for this time of year by Wednesday afternoon, the National Weather Service said.
The flooding happens because a smaller glacier near Mendenhall Glacier had retreated — a casualty of the warming climate — and left a basin that fills with rainwater and snowmelt each spring and summer. When the water creates enough pressure, it forces its way under or around the ice dam created by the Mendenhall Glacier and enters Mendenhall Lake and eventually the Mendenhall River, as it did this week.
Since 2011, the phenomenon has at times flooded streets or homes near the lake and river, and last year floodwaters devoured large chunks of the riverbank, inundated homes and sent at least one residence crashing into the raging river.
But the extent of this week's flooding was unprecedented, officials said, and left residents shaken as they tried to dry out furniture, books and other belongings during a stretch of warm, sunny weather. On Wednesday, piles of garbage bags and other items — wood, boxes, sodden insulation and carpeting — dotted the curbs. A street sweeper was tackling the gray, silty grime the retreating waters had left behind.
While the basin was created by glacial retreat, climate change plays almost no role in the the year-to-year variations in the volume of the flooding in Juneau, said Eran Hood, a professor of environmental science at the University of Alaska Southeast who has studied the Mendenhall Glacier for years.