  We calculate the one-particle hadronic spectra and correlation functions of
pions based on a hydrodynamical model. Parameters in the model are so chosen
that the one-particle spectra reproduce experimental results of
$\sqrt{s}=130A$GeV Au+Au collisions at RHIC. Based on the numerical solution,
we discuss the space-time evolution of the fluid. Two-pion correlation
functions are also discussed. Our numerical solution suggests the formation of
the quark-gluon plasma with large volume and low net baryon density.
