Can I get a 2080s flood-risk projection for a property?

Question

Accepted Answer

Yes for the most flood-exposed UK postcode areas; v1 covers ~30 areas (Severn, Trent, Aire, Don, Thames upper, Cambridgeshire Fens, Lincolnshire coast, Norfolk Broads, Cumbria, South Wales coastal, Devon/Cornwall, London tidal, Hull/East Riding). Postcodes outside the v1 table return 'unknown' source rather than guessing.

How it works: the EA Climate Change Allowances publish multipliers for peak river flow per river-basin district + epoch (2040s / 2050s / 2080s / 2100s) + scenario (central / higher-central / upper-end). Our pure-fn applies the multiplier to today's flood band: a multiplier ≥ 1.2 advances the band one step (eg low → medium); ≥ 1.5 advances two steps (eg low → high). The 2080s + Higher Central scenario is the EA-recommended planning floor + our default.

What you get back: forwardBand (the projected band at the chosen horizon) + bandSteps (how many band-steps the band advanced) + multiplier applied + horizon + scenario + source + plain-language notes.

Use cases:
  - Buyer pre-contract enquiry pack on the conveyancer suite: forward-state 2080s projection alongside today's band.
  - Landlord portfolio risk review: which properties shift from low to medium under +2°C?
  - Mortgage application context: 30-year horizon flood projection.

What v1 does NOT cover (queued for v2):
  - Surface-water (pluvial) forward-state. EA pluvial allowances are still in active research; published as a +20% to +40% range in UKCP18 supplementary guidance, no per-area authoritative table yet.
  - Sea-level-rise forward-state for coastal postcodes.
  - Full per-river-basin GIS ingest (currently a static postcode-area lookup; v2 ingest of the EA CCA shapefile produces per-100m-grid resolution).
  - PDF render on the suite cover (orchestrator integration + SCHEMA_VERSION bump on the audit-cert hash binding are follow-up iters).

Source: EA Climate Change Allowances (last reviewed 2024); UKCP18 plus 1-2-degree scenarios. Methodology + v2 ingest plan: docs/climate-flood-forward-state-2026-05-09.md.

Can I get a 2080s flood-risk projection for a property?

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