ROH §21A-1.11

Building near a watercourse outside flood zones needs approval

Read the official text at honolulu.gov ↗

If you want to build on or next to a watercourse that is not in a mapped flood hazard area, you must get the director's approval first. Your application must include an engineer's signed and stamped report about flood risk. The director may ask other agencies for input, and you must follow floodway or flood fringe rules if they apply. You cannot change the watercourse without approval.

contractorsdeveloperslandowners

The ordinance, as written (Honolulu County) — Developments adjacent to watercourse outside the flood hazard area

A copy, taken August 22, 2026. The version published by Honolulu is the one that governs, and it may have changed since. Check it before relying on anything here.

(a) Applications for building permits for development projects located on property encompassing or adjacent to a property with a watercourse outside of the special flood hazard areas identified on the federal flood maps, shall be subject to review and approval of the director. The application shall include information signed and stamped by a licensed engineer, to evaluate the potential flooding of the area. (b) The director in reviewing the application may consult with other city, State, and federal agencies for their comments and recommendations. If it is determined that the proposed project is within a floodway area, the project shall comply with § 21A-1.7 . If it is determined that the proposed project is within a flood fringe area, the project shall comply with § 21A-1.8 . (c) No watercourse shall be modified, constructed, lined, or altered in any way unless approved by the director.

Read the official text at honolulu.gov ↗as published Jan 1, 2026our copy taken Aug 22, 2026

Published by the City and County of Honolulu through American Legal Publishing.

LawTrove is not legal advice. The summary above is a computer-generated restatement — the authoritative text is the official version linked above.