RiverWatch | Flash Flood & River Flood Risk

Where are flood conditions overlapping with exposed and vulnerable communities?

Data health

Waiting for live sources…

How to read this map

Hazard / signal: Flood alerts / river conditions
Exposure: Population and places
Consequence / vulnerability: Social vulnerability and access consequences

Official/source values remain distinct from MitchellCo derived screening scores or estimates. Derived values are for prioritization and interpretation, not official warnings or predictions.

Map layers & risk legend

USGS river gaugesNWS flood alertsCDC SVI counties

Gauge risk filters

Normal <20Elevated 20–39High 40–64Very high 65–100

Fusion

USGS river hazard + NWS alerts + county population/SVI. Gauge risk colors are derived, not official.

Derived risk

Score = alert + flow + rise + SVI
Alert: 20/25/50/65 · Flow: 8/18/25
Rise=min(20,max(0,ft/hr×20)) · SVI=10×rank · cap 100

Non-official. NWS flood thresholds load from gauge popups.

Live status

USGS gauges0

NWS flood alerts0

CDC counties0

USGS: not loaded

NWS: not loaded

SVI: not loaded

Progressive load0 / 0

Stewardship

Regions load USGS+CDC state-by-state, render progressively, cache results, pause between new chunks, cancel stale work, and pause hidden/offline. NWS uses one alert feed. Refresh: state USGS 15m, regions 60m, NWS 5m.

Sources

USGS · NWS · NWPS · CDC SVI
Basemaps: USGS/OSM/OpenTopoMap/NASA GIBS. FEMA NFHL omitted pending a verified anonymous browser endpoint.