The new, 14,315-square-foot, $3.9 million headquarters replaces an absolute facility built in 1959.
Planning for the new police headquarters began in 2004, but serious considerations didn't begin until several years later.
Two Brothers Construction broke ground in the fall of 2016.
On Saturday, police, public officials and others attended the double ceremony, in which the ribbon was cut and the roadway was dedicated to Long.
Long, who died of a rare form of kidney cancer in June 2016 was a highly respected father of three who worked for the NYPD before transferring to New Milford in 1994.
Long, 46, battled the disease valiantly, returning to work, before succumbing to aggressive renal cell carcinoma a few days short of a special benefit concert for his family sponsored by VFW posts from Bergenfield and Bogota.
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