riskbycounty
FEMA NRI 1.19.0Updated Nov 2023 · Coverage 2014–2023Methodology

Marion County Disaster Risk

Marion County, South Carolina

FEMA Risk Rating

Relatively Low

National Percentile

81th

of 3,144 counties

State Rank

#21

of 46 (1 = highest risk)

Flood Risk

56th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Relatively Low

Higher than 56% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Relatively Low

Higher than 69% of US counties

Tornado

Tornado and severe thunderstorm risk

Relatively Low

Higher than 75% of US counties

Earthquake

Seismic activity and ground shaking risk

Relatively Low

Higher than 80% of US counties

Hurricane

Tropical cyclone and hurricane risk

Relatively High

Higher than 95% of US counties

Risk Overview

About Natural Disaster Risk in Marion County, South Carolina

Marion ranks above average for disaster risk

Marion County scores 80.69 on the national composite risk scale, placing it in the relatively low risk category but notably above South Carolina's average of 70.75. This means Marion faces greater exposure to natural hazards than most of its state neighbors, driven primarily by hurricane vulnerability.

Marion is the 2nd riskiest county in SC

Among South Carolina's 46 counties, Marion ranks second-highest for overall disaster risk, trailing only Richland County. This elevated ranking reflects the county's significant hurricane exposure and above-average flood and wildfire risks.

Marion's risk far exceeds nearby counties

Marion's composite score of 80.69 substantially outpaces neighboring Marlboro County (57.47) and McCormick County (9.54), which rank among the state's safest. Marion's hurricane risk of 94.79 is its defining vulnerability—nearly 20 points higher than Marlboro's neighboring profile.

Hurricanes and earthquakes dominate Marion's threats

Marion's hurricane risk score of 94.79 is the county's most acute hazard, with tropical systems posing direct threats to lives and property throughout the year. Earthquake risk (80.03) and tornado risk (74.97) also merit serious preparation, creating a triple threat that demands comprehensive disaster readiness.

Flood and wind insurance are critical here

Marion residents should prioritize flood insurance, as the county scores 55.50 for flood risk—well above many peers. Given the 94.79 hurricane risk score, securing robust wind and coastal hazard coverage is equally essential for protecting homes and financial stability.

Source: FEMA National Risk Index · Narrative reviewed by Evan Brooks, Data Editor

Preparedness Guide

What to Prepare for in Marion County

Top Hazards by Exposure

  1. #1
    HurricanePrepare
    95th percentile
  2. #2
    EarthquakePrepare
    80th percentile
  3. #3
    TornadoPrepare
    75th percentile

Source: FEMA National Risk Index v1.19.0 · Percentiles are national (3,144 counties)

Risk Advisory: Marion County

Risk Verdict

With a national percentile rank of 81th, Marion County faces below-average hazard exposure relative to U.S. counties as a whole. Proactive preparedness — not reactive response — is key to managing life in one of the country's higher-risk counties; Marion County residents should plan accordingly.

Hazard Breakdown

Hurricane risk is Marion County's dominant natural hazard, ranked at the 95th percentile nationally under FEMA's National Risk Index. Earthquake ranks second at the 80th percentile nationally. Additional tracked hazards include tornado (75th percentile), wildfire (69th percentile), flood (56th percentile).

Preparedness Context

At the 95th percentile nationally for hurricane exposure, Marion County households benefit from reviewing both homeowners and flood insurance coverage before storm season begins — standard policies often exclude storm surge, which is the leading cause of hurricane fatalities. Marion County's earthquake exposure at the 80th percentile nationally adds a hazard layer that can persist or intensify after hurricane-force winds have passed, particularly in low-lying inland areas. Hurricane-force winds cause direct property damage, but storm surge causes the majority of hurricane-related deaths. Marion County households near tidal water or low-elevation areas should verify whether they are in a storm surge risk zone.

Regional Context

At 9.9 points above the South Carolina state average, Marion County carries meaningfully higher natural disaster exposure than a typical South Carolina county.

Is your household prepared for Marion County's hazards?

Review FEMA's county-specific preparedness checklists and emergency planning guides.

FEMA Ready Guide →

Frequently Asked Questions

What is the natural disaster risk in Marion County, SC?
Marion County has a FEMA National Risk Index rating of Relatively Low, placing it in the 81th percentile nationally out of 3,144 counties. This composite score reflects the county's overall exposure to natural hazards including floods, wildfires, tornadoes, earthquakes, and hurricanes, weighted by expected annual loss and social vulnerability.
What types of natural hazards affect Marion County?
Marion County is evaluated for five major natural hazard types: hurricane (95th percentile), earthquake (80th percentile), tornado (75th percentile), wildfire (69th percentile), flooding (56th percentile). The highest-risk hazard is hurricane at the 95th percentile nationally. These scores are derived from FEMA's National Risk Index, which analyzes expected annual loss, social vulnerability, and community resilience for each hazard type.
How does Marion County risk compare to the South Carolina average?
Marion County's composite risk percentile is 81th, compared to the South Carolina state average of 71th percentile. The state's overall risk rating is Relatively Low. This means Marion County faces higher natural disaster risk than the typical county in South Carolina.
Is Marion County at risk for hurricane?
Yes, Marion County's hurricane risk is at the 95th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Marion County is at the 56th percentile.
How is natural disaster risk measured?
FEMA's National Risk Index (NRI) calculates risk scores for 18 natural hazard types across all U.S. counties and census tracts. The composite score combines Expected Annual Loss (estimated dollar losses from each hazard), Social Vulnerability (demographic factors affecting disaster impact), and Community Resilience (ability to recover). Percentile scores rank each county against all 3,144 U.S. counties, and risk ratings range from Very Low to Very High.
Why is Marion County higher risk than average?
Marion County's composite risk score of 81th percentile is above the South Carolina state average of 71th percentile. This elevated risk is driven by hurricane exposure (95th percentile), along with earthquake and tornado and wildfire and flooding risk. Geographic location, terrain, climate patterns, and proximity to flood zones or fault lines all influence a county's risk profile.
By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor

Data Source

Risk data sourced from the FEMA National Risk Index (NRI). Risk scores are relative rankings (0–100) across all US counties — not absolute risk measures. Higher scores indicate higher relative risk compared to other counties.

Disclaimer: This data is informational only. It is not financial, insurance, or legal advice. Always consult a qualified professional before making insurance or real estate decisions.