ZIP 51545 — Climate & Environment

FEMA’s National Risk Index rates natural-hazard risk for River Sioux CDP, IA as Very Low (composite score 31.3), which is relatively lower than many U.S. communities. The strongest component scores on US5 are wildfire (59.8) and flood (37.0). These scores are county-linked NRI values published for planning context — all ZIP codes in the same county share the same composite score on US5. Useful when comparing insurance and disaster exposure across areas, not a substitute for a parcel-level flood or fire determination.