My friend bought a house in Texas on 80 acres with a private 40 acre lake. He said that one of the neighbors is claiming that he has the right to access the lake under Texas law because the stream that feeds into the lake crosses his property. Also, the neighbor claims that his friend whose land is adjacent to the lake on the south side can also access the water because he (the neighbor) gave him an easement. The whole thing doesn't make sense as the legal description marks the boundary of the lake as the shoreline. But not sure if a person whose water feeds into the lake would have any rights to the lake.
Real Estate Attorney
The only way to know for sure is to have a title search done to see if the easement exists. If your friend bought a title policy, the answer may be there.