N.J. Stat. § 27:19-2
If twenty per cent of the legal voters in a county believe that the public convenience requires that a viaduct or bridge should be constructed and maintained in the county, and the board of chosen freeholders has failed or neglected to construct the viaduct or bridge, they may present to the board their petition in writing setting forth the necessity for the viaduct or bridge, the location thereof and other particulars in regard thereto. Upon the filing of the petition with the clerk of the board, duly signed by such voters with their residences opposite their names, and requesting a referendum vote on the question of the construction of the viaduct or bridge, the board of chosen freeholders shall forthwith adopt a resolution that a vote is required upon the question, or it may proceed at once with the construction of the viaduct or bridge or cause it to be constructed, after the adoption of a resolution providing therefor.
N.J.S. § 27:19-2