  Lai (2021) used singular Ricci flows, introduced by Kleiner and Lott (2017),
to construct a nonnegative Ricci curvature Ricci flow $g(t)$ emerging from an
arbitrary 3D complete noncompact Riemannian manifold $(M^3, g_0)$ which has
nonnegative Ricci curvature. We show $g(t)$ is complete for positive times
provided $g_0$ satisfies a volume ratio lower bound that approaches zero at
spatial infinity. Our proof combines a pseudolocality result of Lai (2021) for
singular flows, together with a pseudolocality result of Hochard (2016) and
Simon and Topping (2022) for nonsingular flows. We also show that the
construction of complete nonnegative complex sectional curvature flows by
Cabezas-Rivas and Wilking (2015) can be adapted here to show $g(t)$ is complete
for positive times provided $g_0$ is a compactly supported perturbation of a
nonnegative sectional curvature metric on $\mathbb{R}^3$.
