Section Env-Wt 517.05 - Design and Construction Requirements for Boardwalks In addition to meeting the applicable design and construction criteria in Env-Wt 300, boardwalks shall meet the following design and construction requirements:
(a) Boardwalks shall not be located in or through any PRA if the use associated with the boardwalk would jeopardize the continued existence of protected species or habitat;(b) To allow for circulation of air and water and penetration of light, boardwalks shall be designed and constructed:(1) To be elevated not less than 4 feet for tidal wetlands and at least 2 feet for non-tidal wetlands above the ground surface or normal high water line, as applicable; and(2) With grating, or slatted decking with boards no wider than 8 to 10 inches, spaced no less than 0.75 inches apart, or if necessary to meet ADA requirements, no less than 0.5 inches apart;(c) Boardwalks shall be at least 3 feet wide and no wider than 6 feet;(d) Boardwalks crossing wetlands shall be designed and located to:(1) Allow for movement of wildlife and maintain density and vigor of vegetation; and(2) Minimize interference with the natural hydrology of the area;(e) Boardwalks shall incorporate features designed to educate users about the importance of wetlands, transition areas, and public waters;(f) Boardwalks shall be constructed using top-down construction methods, helical piles, and other methods to limit impacts to sensitive wetlands and surface waters;(g) A boardwalk shall not be supported by horizontal support timbers, otherwise known as sleepers, on or in the soil, except that on hiking trails, a log foot bridge may have timber sleepers on the soils; and(h) The root mat and soil under and around the boardwalk shall not be disturbed except to drive pilings.N.H. Admin. Code § Env-Wt 517.05
Derived from Volume XXXIX Number 28, Filed July 11, 2019, Proposed by #12805, Effective 12/15/2019, Expires 12/15/2029 (See Revision Notes #1 and #2 at chapter heading for Env-Wt 500).Amended by Volume XL Number 46, Filed November 12, 2020, Proposed by #13124, Effective 10/23/2020, Expires 10/23/2030.Amended by Number 45, Filed November 9, 2023, Proposed by #13776, Effective 10/13/2023, Expires 10/13/2033.