The suspected drunk driver accused of mowing down 10 people, killing three, at a Fourth of July celebration on the Lower East Side is a substance-abuse counselor and author of “The Sober Addict” — who claims his passion is to help “prevent death,” The Post can reveal.

Daniel Christopher Hyden, 44, has been arrested and charged with drinking under the influence after he allegedly drove a gray Ford F-150 through the Water Street and Jackson Street intersection, over the sidewalk and into people — including children — celebrating at Corlears Hook Park, according to police.