N.H. Rev. Stat. Ann. § 233-A:15

The executive director shall adopt rules pursuant to RSA 541-A to permit operators of non-motorized boats and others that use public boat access areas to make donations to support the development and maintenance of such areas. The program may include various methods of advertising the program, such as posted signs at access areas, and recognizing those who have contributed, such as with a sticker, card, or letter of thanks. All funds collected pursuant to this paragraph shall be deposited into the statewide public boat access fund established in RSA 233-A:13.