  Quantum transport properties in quantum Hall wires in the presence of
spatially correlated random potential are investigated numerically. It is found
that the potential correlation reduces the localization length associated with
the edge state, in contrast to the naive expectation that the potential
correlation increases it. The effect appears as the sizable shift of quantized
conductance plateaus in long wires, where the plateau transitions occur at
energies much higher than the Landau band centers. The scale of the shift is of
the order of the strength of the random potential and is insensitive to the
strength of magnetic fields. Experimental implications are also discussed.
