N.J. Stat. § 40:48-3
When, by this subtitle, the governing body of any municipality is given power to order the owner of any real estate therein, to make any improvement or to do any work thereon, or upon any street upon which his real estate abuts, and he refuses or neglects to make such improvement or do such work after being so ordered, the municipality after notice to him of its intention so to do, may cause such improvement to be made or work to be done, and may recover the cost thereof from him by action at law. Such action shall be in addition to any other remedy given by this subtitle and shall not make void any lien hereby given upon such real estate, nor prevent the imposition of any penalty imposed for violation of any ordinance of the municipality.
N.J.S. § 40:48-3