A very old Ahtna trail ran along the Klutina River and a segment of it eventually became Klutina Lake Road. Ahtna people, like the other Native people in Alaska, negotiated with the fed govt to confirm their claims  to lands they had possessed for thousands of years, in return for giving up claim to other of their lands to the State of Alaska and other entities. Under the resulting ANCSA legislation Ahtna made their land selections (including Klutina Lake and surrounds), pared down from a very much larger original ancient known and documented land base. To characterize it as "Ahtna selected those lands after the road existed" misrepresents the situation. As others point out, access to the lake wouldn't be blocked; only unauthorized use of surrounding Ahtna land.