N.H. Rev. Stat. Ann. § 423:3

Whenever a town finds it necessary to acquire land for the purposes hereof beyond its boundaries and is unable to acquire it for a reasonable price by purchase or lease, the town may institute eminent domain proceedings by petition to the county commissioners, and the procedure followed by the commissioners as respects notice, assessment and payment of damages, entry and appeal shall, so far as applicable, be the same as that prescribed for the public utilities commission in the case of taking land by a public utility as provided in RSA 371:1-13, inclusive.