Wayne, NJ Environmental Rules: Flood Elevation Requirements (2026)

Wayne Township builds its flood elevation standard around the Local Design Flood Elevation, or LDFE, in § 134-97.1B(3). The LDFE is established using the best available flood hazard data sources, the Flood Hazard Area Control Act minimum Statewide elevation requirements for lowest floors in A, Coastal A, and V zones, ASCE 24 requirements for critical facilities, plus additional freeboard as specified by the chapter.

At a minimum, the LDFE for a delineated watercourse is the elevation associated with the Best Available Flood Hazard Data Area plus one foot, or as described by N.J.A.C. 7:13, of freeboard. For an undelineated watercourse with a contributory drainage area of 50 acres or more, the applicant provides either an unexpired NJDEP Flood Hazard Area Verification plus one foot of freeboard and any additional freeboard required by ASCE 24, or a determination using Method 5 or Method 6 under N.J.A.C. 7:13, also plus one foot of freeboard. Any Method 5 or 6 determination must be sealed and submitted under § 134-97.1E(2) to (3).

In AO Zones the LDFE is the highest adjacent grade plus the depth number specified plus one foot of freeboard. If no depth number is specified, the LDFE is three feet above the highest adjacent grade. For new and substantially improved Flood Design Class IV Critical Facilities, the LDFE must be the higher of the 0.2% annual chance (500 year) flood elevation or the Flood Hazard Area Design Flood Elevation with an additional two feet of freeboard. Class III Critical Facilities in coastal high hazard areas get an additional one foot of freeboard on the same comparison.

The LDFE is then used as the floor line. Under § 134-97.8A, all new construction and substantial improvement of any habitable building in flood hazard areas must have the lowest floor, including basement, together with attendant utilities and sanitary facilities, elevated to or above the LDFE, in conformance with ASCE Chapter 7, and confirmed by an Elevation Certificate. Non-residential structures can alternatively be floodproofed below the LDFE under ASCE 24 Chapters 2 and 7.