  Charge density wave (CDW) correlations feature prominently in the phase
diagram of the cuprates, motivating competing theories of whether fluctuating
CDW correlations aid superconductivity or whether static CDW order coexists
with superconductivity in inhomogeneous or spatially modulated states. Here we
report Cu $L$-edge resonant x-ray photon correlation spectroscopy (XPCS)
measurements of CDW correlations in superconducting La$_{2-x}$Ba$_x$CuO$_4$
$x=0.11$. Static CDW order is shown to exist in the superconducting state at
low temperatures and to persist up to at least 85\% of the CDW transition
temperature. We discuss the implications of our observations for how
\emph{nominally} competing order parameters can coexist in the cuprates.
