The interaction of three nonlinearly coupled drift waves is investigated for the occurrence of stochastization of the phases and the applicability of the random phase approximation. The drift wave nonlinearities include the E×B and polarization drift couplings for waves that are linearly unstable for appropriate values of the perpendicular wavenumber. The conservation properties and sample numerical solutions for the exact three wave interaction are given along with the conservation properties and solutions of the corresponding random phase approximation equations.