  We study the energy dependence of the saturation momentum in the context of
the collinearly improved Leading and Next to Leading BFKL evolution, and in the
presence of saturation boundaries. We find that the logarithmic derivative of
the saturation momentum is varying very slowly with Bjorken-x, and its value is
in agreement with the Golec-Biernat and Wusthoff model in the relevant x
region. The scaling form of the amplitude for dipole-dipole or dipole-hadron
scattering in the perturbative side of the boundary is given.
