SLR-XA (Sea Level Rise Exposure Area)
The Sea Level Rise Exposure Area (SLR-XA) is the State of Hawaiʻi's mapped coastal-exposure zone — the land projected to be affected under 3.2 feet of sea level rise, combining passive flooding, annual high-wave flooding, and coastal erosion. It is the map behind Act 179 (2021), which made Hawaiʻi the first state to require sea-level-rise disclosure in residential real estate sales.
The SLR-XA comes from the State's Sea Level Rise Vulnerability and Adaptation Report (2017), which modeled exposure at 0.5, 1.1, 2.0, and 3.2 feet of rise. The 3.2-ft scenario is the codified benchmark: it maps the three hazard families federal flood maps don't combine for Hawaiʻi — passive marine flooding, annual high-wave run-up, and projected erosion. The Commission's 2022 update treats 3.2 ft as mid-range rather than upper-end and recommends planning to 4 ft (6 ft for critical infrastructure), though no parcel-grade statewide mapping exists above 3.2 ft yet.
Act 179 (Session Laws of Hawaiʻi 2021, from SB 474) amended the mandatory seller-disclosure law, HRS Chapter 508D, effective May 1, 2022: a seller of residential property must disclose whether any portion of the property lies within the SLR-XA. That makes SLR-XA membership a material fact in a transaction, not just a planning abstraction.
The SLR-XA is distinct from a FEMA flood zone. FEMA's maps drive flood-insurance and lender requirements today; the SLR-XA is a forward-looking planning screen. A parcel can sit outside the FEMA Special Flood Hazard Area and inside the SLR-XA, or vice versa — and a parcel outside the mapped SLR-XA has a mapping result, not a coastal-hazard clearance.
On a coastal parcel, SLR-XA membership means a disclosure obligation on resale and a design, financing, and insurance conversation during ownership. Reading the parcel's exposure across the mapped scenarios early — and which hazard family drives it — tells you whether sea-level rise is a pricing input on this deal or a non-issue at the mapped horizon.
The Sea Level Rise Exposure Area — the State's mapped zone of land projected to be affected under 3.2 feet of sea level rise, combining passive flooding, annual high-wave flooding, and erosion. It's the mapped product behind Hawaiʻi's real-estate sea-level-rise disclosure.
Yes. Under Act 179 (2021), effective May 1, 2022, HRS Chapter 508D requires sellers of residential property to disclose whether any portion of the property lies within the Sea Level Rise Exposure Area.
This is a plain-language reference, not legal advice. KILO is a pre-development screening tool, not a system of record — confirm any determination with the agency of jurisdiction.