Lake Shasta was a lake in California, on Earth.
Lieutenant Ash Tyler owned a lake house near this lake. Voq, while Tyler, said he saw himself after the first Federation-Klingon War in a little sailboat catching trout and then fresh-roasting the fish. After having his dinner, he would camp at the beach, watching the stars fall. (DIS: "Si Vis Pacem, Para Bellum")
StarTrek.com described Lake Shasta as a "reservoir". [1](X)