N.J. Stat. § 58:5-18
The commission may construct water mains or pipe lines for the purposes provided for in this chapter along, under and over any watercourse, or under, over, along or across any street, turnpike, road, railroad, highway or other way, or public park or grounds, and in or upon private or public land under water, in such way and manner as not unnecessarily to obstruct or impede travel or navigation.
It may enter upon and dig up any street, highway or private or public land, for the purpose of constructing said work and appurtenances and for repairing and maintaining the same, and in a general way may do all other acts and things necessary, convenient and proper in connection with the acquisition, construction, operation and maintenance of said water supply. If any highway or public or private land is dug up and disturbed pursuant to the provisions of this chapter, the same shall be restored to its former condition as nearly as may be.
The commission may also alter or change the grade of any highway or public street, or relocate such highway or street where necessary for the purpose of constructing any reservoirs to be built in accordance with contracts authorized to be made by this chapter. If it shall become necessary to change the location or gradient of any canal or railroad, or the appurtenances thereof, the corporation owning or operating such canal or railroad shall be required to relocate or change the same as far as needful and to acquire the property necessary for such change and, if possible, to agree with the commission upon the details of such change, the cost thereof to be paid by the commission as a part of the expense of such reservoir construction. If the corporation is unable to agree with the owner of any land, property or right required to be taken by it in order to make such change, the commission shall, for the benefit of the corporation, acquire the same by condemnation or otherwise, provided such acquisition shall not impair the operation of the railroad or canal.
N.J.S. § 58:5-18