  The survey description and the near-, mid-, and far-infrared flux properties
are presented for the 258 galaxies in the Local Volume Legacy (LVL). LVL is a
Spitzer Space Telescope legacy program that surveys the local universe out to
11 Mpc, built upon a foundation of ultraviolet, H-alpha, and HST imaging from
11HUGS (11 Mpc H-alpha and Ultraviolet Galaxy Survey) and ANGST (ACS Nearby
Galaxy Survey Treasury). LVL covers an unbiased, representative, and
statistically robust sample of nearby star-forming galaxies, exploiting the
highest extragalactic spatial resolution achievable with Spitzer. As a result
of its approximately volume-limited nature, LVL augments previous Spitzer
observations of present-day galaxies with improved sampling of the
low-luminosity galaxy population. The collection of LVL galaxies shows a large
spread in mid-infrared colors, likely due to the conspicuous deficiency of 8um
PAH emission from low-metallicity, low-luminosity galaxies. Conversely, the
far-infrared emission tightly tracks the total infrared emission, with a
dispersion in their flux ratio of only 0.1 dex. In terms of the relation
between infrared-to-ultraviolet ratio and ultraviolet spectral slope, the LVL
sample shows redder colors and/or lower infrared-to-ultraviolet ratios than
starburst galaxies, suggesting that reprocessing by dust is less important in
the lower mass systems that dominate the LVL sample. Comparisons with
theoretical models suggest that the amplitude of deviations from the relation
found for starburst galaxies correlates with the age of the stellar populations
that dominate the ultraviolet/optical luminosities.
