Swimming in a glacier lake

When we lived in Alaska, we would swim in the summer at a place called Falk's Lake. It was on the farm of the Falk family, and I guess they let everyone swim there. Mom would usually load up the Hudson with a bunch of kids from Eklutna, the tiny community where we lived, and lug us there. She was the only mom who did this, by the way. The water was always very cold, very cold, but Tootie would dive right in. She was first in, last out. I took a lot longer to get in, but once in, was fine. I remember one time a friend of ours came out of the lake with a headache. The next day, he was paralyzed. In those days, summer was polio season, and everybody worried about it.