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The Flood Zone Shift

Where FEMA redrew the lines — and what it costs you.

Purpose

This investigation maps the geography of FEMA flood zone reclassifications across Houston metro counties (Harris, Fort Bend, Montgomery), revealing how federal risk redrawing reshapes insurance costs, property values, and neighborhood vulnerability. Built from FEMA CSLF and NFHL data with real-time address lookup.

Why It Matters

When FEMA redraws a flood zone boundary, it changes what homeowners pay for insurance, what their property is worth, and whether they can get a mortgage. These decisions happen quietly and affect millions — but most residents only find out when the bill arrives.

Explore the Data

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Methodology

Real-time FEMA CSLF API queries for SFHA change polygons across Houston metro counties. Address lookup queries both effective and pending NFHL layers. Insurance estimates from FEMA Risk Rating 2.0 ZIP-level medians. 46,676 total zone change records, 653 mapped GeoJSON features.

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Citation

Local Insights Civic Data Lab. The Flood Zone Shift. https://localinsights.ai/products/flood-zone-shift