Lakes

How are lakes formed ?

River, dune, landslide and coastal barrier lakes are all formed by natural processes that change the drainage and cause water to pond up. When a river changes its course during a flood, part of the old channel is often left behind as a lake.

or ... when glaciers melt the water gets pushed around and forced to follow the ice and while the ice is caving the land as it moves the leaves the water to be left behind.

as the glaciers moves it makes a path until it hit a flat and melts turning the glaciers into a pond and as it rains the rain with follow down the mountain and filling up the lake with rain water. most of the north Americas lakes are made out of a big glaciers

There can also be a spring witch may seep out of the ground over years slowly adding more and more water to the lake.