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

Section 154-2.3 of the Howell Township Code establishes the local design flood elevation (LDFE) in the flood hazard areas mapped under § 154-2.2. It rests on the best available flood hazard data, the Flood Hazard Area Control Act minimum statewide elevation requirements for lowest floors in A, Coastal A and V Zones, and ASCE 24 requirements for critical facilities, plus the additional freeboard the chapter specifies.

The printed minimums are as follows. For a delineated watercourse, the LDFE is the elevation from the best available data plus one foot, or the freeboard described by N.J.A.C. 7:13. For an undelineated watercourse with a contributory drainage area of 50 acres or more, the applicant supplies either an unexpired NJDEP flood hazard area verification plus one foot of freeboard and any ASCE 24 additional freeboard, or a Method 5 or Method 6 determination under N.J.A.C. 7:13 plus the same freeboard, sealed and submitted under § 154-5.2A(3). In Zone AO, the LDFE is the highest adjacent grade plus the depth number on the FIRM plus one foot, and with no depth number it is three feet above the highest adjacent grade. New and substantially improved Class IV critical facilities must meet the higher of the 0.2% annual chance (500-year) flood elevation or the flood hazard area design flood elevation with two additional feet of freeboard. Class III critical facilities in coastal high hazard areas get the same higher-of test with one additional foot.

When design flood elevations are not specified, § 154-3.7 lets the Floodplain Administrator require the applicant to use available federal or state data or to run an engineer-sealed hydrologic and hydraulic analysis, and the applicant is responsible for the accuracy of the data. Under § 154-3.15 the Administrator records the required elevation, determination method and base flood elevation source in the floodplain development permit.