State has the requisite jurisdiction to issue executive instructions in relation to the matters covered under its legislative competence. If, therefore, for certain purposes executive instructions and/or statutory orders have been issued prohibiting conversion of agricultural land for another purpose namely for irrigation or for some other purpose whatsoever by the State/Board of Revenue, the same cannot be said to be bad in law. Deep underground water belongs to the State in the sense that doctrine of public trust extends thereto. A person who holds land for agricultural purpose may, subject to reasonable restriction that may be made by the State may have the right to use water for irrigational purposes and for the said purpose he may also excavate a tank. But under no circumstances, he can be permitted to restrict the flow of water to the neighboring lands or discharge the effluents in such a manner so as to affect the right of his neighbor to use water for his own purposes. [ M.P.Rambabu vs D.F.O. AIR 2002 AP 256. S.B.Sinha (CJ) & V.V.S.Rao (J)]