Summary
Plan status as of 2026-09-30: Approved, expires 2029-03-19. Plan: Charleston County (FEMA plan 109656), approved 2024-03-20.
Since the plan was approved on 2024-03-20: 3 new hazard declarations (3 incidents): EM-3606-SC (Hurricane Debby), EM-3619-SC (Hurricane Helene), EM-3632-SC (Severe Winter Storm).
NOAA Storm Events records since that date: 131 records (data through 2026-06-30).
Highest expected annual loss (FEMA National Risk Index, modeled total; see B1-a): Hurricane ($281,333,148 a year), Earthquake ($117,992,986) and Inland Flooding ($44,209,893).
Repetitive-loss flood properties now: FMA RL 79, SRL 228 (44 CFR 77.2); any definition: 1,296.
The tables that follow are organized by the items of FEMA's Local Mitigation Plan Review Tool, Element B (B1-a to B2-c); each heading says which item its tables support.
Plan clock
- Status:
- Approved, expires 2029-03-19
- Plan:
- Charleston County (FEMA plan 109656)
- Approved:
- 2024-03-20
- Days to expiry:
- 901
What changed since your last plan (approved 2024-03-20)
- New federal declarations:
- 3 new hazard declarations (3 incidents): EM-3606-SC (Hurricane Debby), EM-3619-SC (Hurricane Helene), EM-3632-SC (Severe Winter Storm)
- Storm Events records since approval:
- 131 records (data through 2026-06-30)
- Repetitive loss now:
- FMA RL 79, SRL 228 (44 CFR 77.2); any definition: 1,296
- Repeat-flood change:
- this release sets the baseline count.
Sources: 1, 2, 4, 6 (numbered list at the end)
Plan status for every jurisdiction listed in this county: 33 rows, in the section "Plan clock: Plan status for every jurisdiction listed in this county" on the following pages.
State plan status and tribal plans in this state: see the state page.
Plan clock
Plan status for every jurisdiction listed in this county
Source: 1
| Jurisdiction | Type | Status | Plan | Approved | Expires | Days to expirynegative = days since expiry | Update underway | Notes |
|---|---|---|---|---|---|---|---|---|
| Charleston County (unincorporated area) | Unincorporated | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | this jurisdiction approved 2024-03-28 | |
| Awendaw town | Town | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Charleston city | City | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | FEMA tracker shows a plan approvable pending adoption | Not yet eligible: adopt the approved plan. |
| Folly Beach city | City | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | this jurisdiction approved 2024-03-28 | |
| Hollywood town | Town | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Isle of Palms city | City | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | this jurisdiction approved 2024-03-28 | |
| James Island town | Town | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Kiawah Island town | Town | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Lincolnville town | Town | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | this jurisdiction approved 2026-02-10 | |
| McClellanville town | Town | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Meggett town | Town | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Mount Pleasant town | Town | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | Also approved under plan 109525 (Mount Pleasant, expires 2029-02-20). FEMA's plan status map shows one plan per jurisdiction and may show one of these; this packet uses the approved plan that expires last. | |
| North Charleston city | City | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Ravenel town | Town | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Rockville town | Town | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Seabrook Island town | Town | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Sullivan's Island town | Town | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | this jurisdiction approved 2024-03-28 | |
| Summerville town | Town | Expired on 2026-07-06 | Dorchester County (FEMA plan 106789) | 2021-07-07 | 2026-07-06 | -86 | this jurisdiction approved 2021-08-23 | |
| Charleston County School District | School/School District | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | this jurisdiction approved 2024-03-28 | |
| Charleston Co. Park and Recreation Commission | Special District | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Charleston Water System | Water/Sewer Authority | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| College of Charleston | College/University | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Cooper River Park and Playground Commission | Special District | Plan 109656 approved 2024-03-20, pending adoption here; not yet eligible | Charleston County (FEMA plan 109656), pending adoption here | 2024-03-20 by FEMA; not yet adopted here | 2029-03-19 once adopted | FEMA tracker shows a plan approvable pending adoption | Not yet eligible: adopt the approved plan. | |
| James Island Public Service District | Special District | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Mt. Pleasant Waterworks | Water/Sewer Authority | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| North Charleston District Commission | Special District | Plan 109656 approved 2024-03-20, pending adoption here; not yet eligible | Charleston County (FEMA plan 109656), pending adoption here | 2024-03-20 by FEMA; not yet adopted here | 2029-03-19 once adopted | FEMA tracker shows a plan approvable pending adoption | Not yet eligible: adopt the approved plan. | |
| North Charleston Sewer District | Water/Sewer Authority | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| Roper St. Francis | Hospital/Medical Facility | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | this jurisdiction approved 2024-04-16 | |
| St. Andrews Parish Parks and Recreation Commission | Special District | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| St. Andrews Public Service District | Special District | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | this jurisdiction approved 2024-06-28 | |
| St. John's Fire Department | Fire/EMS District | Plan 109656 approved 2024-03-20, pending adoption here; not yet eligible | Charleston County (FEMA plan 109656), pending adoption here | 2024-03-20 by FEMA; not yet adopted here | 2029-03-19 once adopted | FEMA tracker shows a plan approvable pending adoption | Not yet eligible: adopt the approved plan. | |
| St.Paul's Fire District | Fire/EMS District | Approved, expires 2029-03-19 | Charleston County (FEMA plan 109656) | 2024-03-20 | 2029-03-19 | 901 | ||
| The Citadel | College/University | Approved, expires 2029-09-02 | The Citadel (FEMA plan 109144) | 2024-09-03 | 2029-09-02 | 1,068 |
Supports FEMA checklist item B1-a: hazard identification
Hazards NRI does not cover (local data needed)
- dam failure (incl. upstream dams)
- levee failure
- flash flood as its own subtype
- ice jams
- debris flows
- erosion (riverine and coastal)
- land subsidence and sinkholes
- expansive soils
The 18 National Risk Index hazards, ranked by expected annual loss (EAL)
Sources: 5, 6
| Rank by EAL | Hazard | NRI risk rating | EAL rating | EAL buildingsmodeled dollars per year | EAL agriculturemodeled dollars per year | Cost of expected deaths and injuriesFEMA's dollar value per year, not property damage | EAL total (see note)modeled dollars per year | Storm Events records, 1996 to 2026-06-30count | Storm Events coverage note |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Hurricane | Very High | Very High | $263,973,600 | $428,384 | $16,931,164 | $281,333,148 | 36 | Includes 4 Tropical Depression records (outside NRI's Hurricane definition). |
| 2 | Earthquake | Relatively High | Relatively High | $68,175,993 | n/a | $49,816,994 | $117,992,986 | Storm Events does not record earthquakes. | |
| 3 | Inland Flooding | Relatively Moderate | Relatively Moderate | $42,615,234 | $406,115 | $1,188,544 | $44,209,893 | 311 | |
| 4 | Coastal Flooding | Very High | Very High | $31,731,585 | n/a | $3,902,587 | $35,634,176 | 85 | |
| 5 | Cold Wave | Relatively Moderate | Relatively High | $53,389 | $17,708 | $6,523,611 | $6,594,707 | 6 | Includes 2 Frost/Freeze records (outside NRI's Cold Wave definition; counted in this table and in B1-d, not in the B1-e descriptor). |
| 6 | Wildfire | Relatively Moderate | Relatively Moderate | $2,832,936 | $296 | $244,626 | $3,077,857 | 4 | |
| 7 | Tornado | Relatively Moderate | Relatively Moderate | $767,451 | $474 | $2,251,337 | $3,019,263 | 43 | |
| 8 | Heat Wave | Relatively Moderate | Relatively Moderate | $625 | $75 | $2,034,056 | $2,034,756 | 19 | |
| 9 | Ice Storm | Relatively High | Very High | $1,538,417 | n/a | $213,453 | $1,751,870 | 4 | |
| 10 | Strong Wind | Relatively Moderate | Relatively High | $51,576 | $154 | $1,638,459 | $1,690,189 | 575 | Includes 10 High Wind and 43 Strong Wind records (NOAA non-thunderstorm wind types, outside NRI's Strong Wind definition). |
| 11 | Lightning | Relatively High | Relatively High | $86,270 | n/a | $1,570,620 | $1,656,890 | 47 | |
| 12 | Hail | Relatively Low | Relatively Low | $33,841 | $727 | $416,771 | $451,339 | 273 | |
| 13 | Winter Weather | Relatively Moderate | Relatively High | $91,917 | $15 | $209,072 | $301,004 | 12 | |
| 14 | Drought | Relatively Low | Relatively Low | n/a | $50,004 | n/a | $50,004 | 20 | |
| 15 | Landslide | Very Low | Very Low | $649 | n/a | $1 | $650 | 0 | Declared 1 time; no Storm Events record of this type. |
| Tsunami | Insufficient Data | Insufficient Data | n/a | n/a | n/a | n/a | 0 | No recorded events in Storm Events since 1996 (data through 2026-06-30). |
Total = buildings + agriculture + population equivalence; FEMA values each expected death (or 10 injuries) at $13.7 million (2024 dollars).
NRI risk rating combines expected annual loss with social vulnerability and community resilience; EAL rating rates expected annual loss alone. Both compare this county with all U.S. counties.
Local data needed: state and local landslide and tsunami records (Storm Events records these hazards only in part).
Not applicable to this county per NRI, with no federal declaration and no Storm Events record since 1996: avalanche and volcanic activity. That is the evidence for leaving them out of the plan.
The state hazard mitigation plan also lists hazards for this county; FEMA asks the plan to explain any hazard it leaves out.
Supports FEMA checklist item B1-b: hazard location
Affects the whole county (national data give no location within it): Cold Wave, Drought, Hail, Heat Wave, Ice Storm, Lightning, Strong Wind and Winter Weather.
Coastal Flooding and Inland Flooding: The FEMA Flood Insurance Rate Map (FIRM) is the required location source for flooding. See the FEMA Flood Map Service Center (https://msc.fema.gov) for this county.
Hazards that vary within the county: highest-rated census tracts
Source: 5
| Hazard | Highest-rated census tractsNRI risk rating, score 0 to 100 |
|---|---|
| Earthquake | tract 39 (Very High, 99.2); tract 31.15 (Very High, 99.1); tract 55 (Very High, 99.0) |
| Hurricane | tract 21.04 (Very High, 99.9); tract 46.14 (Very High, 99.9); tract 34 (Very High, 99.8) |
| Landslide | tract 21.05 (Very Low, 78.5); tract 23 (Very Low, 78.1); tract 50.01 (Very Low, 77.0) |
| Tornado | tract 31.06 (Relatively Moderate, 61.4); tract 31.15 (Relatively Low, 52.2); tract 58 (Relatively Low, 51.3) |
| Tsunami | no tract has a National Risk Index rating for this hazard |
| Wildfire | tract 50.02 (Relatively High, 97.4); tract 50.01 (Relatively Moderate, 96.0); tract 21.04 (Relatively Moderate, 96.0) |
Up to 3 census tracts per hazard, highest National Risk Index rating first, then highest score; a tract number is the Census tract number (for example 39 is Census Tract 39). FEMA's Resilience Analysis and Planning Tool maps the National Risk Index for every tract: https://www.fema.gov/emergency-managers/practitioners/resilience-analysis-and-planning-tool
Supports FEMA checklist item B1-c: hazard extent
Extent: scale, observed range and worst recorded event per hazard
Sources: 6, 7
| Hazard | Scale | Recordscount and years | Observed range | Worst recorded event | Most damaging (when different) | How it applies to jurisdictions | Note |
|---|---|---|---|---|---|---|---|
| Coastal Flood, Storm Surge/Tide | none in data (flood depth: FIRM) | 85 records, 2009 to 2025 (85 zone-level) | Coastal Flood, 2009-06-22, $100,000 property; crops not reported (2009 dollars); NWS zone SCZ050 | Countywide (zone-level records). | Flood depth: see the FEMA Flood Insurance Rate Map. | ||
| Cold/Wind Chill, Extreme Cold/Wind Chill | wind chill | 4 records, 1996 to 2026 (4 zone-level) | 1 day to 3 days (median 2 days); 3 with a recorded value | 3 consecutive days, 1996-02-03 to 1996-02-05, 1 direct death, zone-level | Countywide (zone-level records). | Wind chill: in event narratives only (local data needed). | |
| Frost/Freeze (outside NRI's Cold Wave definition) | crop damage | 2 records, 2007 to 2022 (2 zone-level) | No crop damage reported in 2 records. | Countywide (zone-level records). | Temperature: in event narratives only (local data needed). | ||
| Drought | U.S. Drought Monitor scale (D0 to D4) | 20 records, 1996 to 2002 (20 zone-level) | 23 days to 214 days (median 60 days); 7 with a recorded value | 214 days (7 months), 2002-03-01 to 2002-09-30, a run of 7 consecutive Storm Events drought records, zone-level | Countywide (zone-level records). | Storm Events enters a drought at D2 or worse east of the Rockies and D3 or worse from the Rockies west (NWS Instruction 10-1605); NRI drought counts D3 and D4 only. | |
| Earthquake | Modified Mercalli (local data) | 0 | Storm Events does not record earthquakes; the USGS earthquake catalog is the source. | ||||
| Hail | hail size (inches) | 300 records, 1957 to 2026 | 0.75 in to 2.75 in (median 1 in); 299 with a recorded value | 2.75 in hail, 2011-05-10 | Hail, 2011-05-10, $30,000 property; $0 crops (2011 dollars) | Event records naming jurisdictions in the plan: Charleston city (24 records), North Charleston city (13 records), Mount Pleasant town (9 records), Awendaw town (8 records), Ravenel town (5 records), Folly Beach city (3 records), Isle of Palms city (3 records), Hollywood town (2 records), Lincolnville town (2 records), Rockville town (2 records). | |
| Excessive Heat, Heat | heat index (in event narratives) | 19 records, 1996 to 2021 (19 zone-level) | 1 day to 31 days (median 2 days); 14 with a recorded value | August 1999 (1 monthly summary record), 6 direct deaths, zone-level | Countywide (zone-level records). | Heat index: in event narratives only (local data needed). | |
| Hurricane, Tropical Storm, Tropical Depression | Saffir-Simpson | 36 records, 1996 to 2024 (36 zone-level) | Strongest recorded: Hurricane (Typhoon) record (NOAA's event type name), 1996-07-12, 50 kt (58 mph), measurement type not recorded, damage not reported; NWS zone SCZ050 | Most damaging recorded: Tropical Storm, 2004-08-29, $16,600,000 property; crops not reported, reported for the zone (2004 dollars) | Countywide (zone-level records). | Storm Events files every zone of a storm's episode under the storm's type; flooding from the storm is filed as Flood or Flash Flood records. | |
| Ice Storm | Sperry-Piltz ice scale (local data) | 4 records, 2004 to 2014 (4 zone-level) | Ice Storm, 2011-01-10, $150,000 property; $0 crops (2011 dollars); NWS zone SCZ050 | Countywide (zone-level records). | Ice thickness: in event narratives only (local data needed). | ||
| Flash Flood, Flood, Lakeshore Flood | damage and flood days (flood depth: FIRM) | 311 records, 1996 to 2026 (3 zone-level) | Flash Flood, 2012-08-28, $750,000 property; $0 crops (2012 dollars) | Event records naming jurisdictions in the plan: Charleston city (83 records), Awendaw town (9 records), Mount Pleasant town (9 records), North Charleston city (8 records), Folly Beach city (4 records), Rockville town (3 records), Hollywood town (2 records), Meggett town (2 records), Isle of Palms city (1 record), Lincolnville town (1 record); and 1 more jurisdiction (see the Excel file). Zone-level records (3) apply countywide. | Flood depth: see the FEMA Flood Insurance Rate Map. Storm Events damage is often $0 or blank for floods, major ones included; FEMA Public Assistance by declaration (B1-d) shows which floods cost the most. | ||
| Debris Flow | none (count and damage only) | 0 | Physical measure: in event narratives only (local data needed). | ||||
| Lightning | annualized frequency (the measure FEMA's Local Mitigation Planning Handbook names) | 47 records, 1998 to 2025 | Lightning, 2005-06-18, damage not reported, 1 direct death | Lightning, 2000-04-17, $500,000 property; crops not reported (2000 dollars) | Event records naming jurisdictions in the plan: North Charleston city (3 records), Awendaw town (2 records), Mount Pleasant town (2 records), Charleston city (1 record), Folly Beach city (1 record), Isle of Palms city (1 record), Ravenel town (1 record). | Storm Events lists lightning with damage or casualties; physical measure in event narratives only (local data needed). | |
| High Wind and Strong Wind (outside NRI's Strong Wind definition) | wind speed (kt and mph) | 53 records, 2004 to 2024 (53 zone-level) | 22 kt (25 mph) to 60 kt (69 mph) (median 40 kt (46 mph)); 53 with a recorded value | 60 kt (69 mph) measured gust, High Wind, 2024-01-09; NWS zone SCZ050 | High Wind, 2022-03-12, $10,000 property; $0 crops, reported for the zone (2022 dollars) | Countywide (zone-level records). | |
| Thunderstorm Wind | wind speed (kt and mph) | 624 records, 1955 to 2026 | 35 kt (40 mph) to 83 kt (96 mph) (median 50 kt (58 mph)); 541 with a recorded value | 83 kt (96 mph) estimated gust, Thunderstorm Wind, 2022-04-05 | Thunderstorm Wind, 2000-08-11, $200,000 property; crops not reported (2000 dollars) | Event records naming jurisdictions in the plan: Charleston city (31 records), North Charleston city (22 records), Rockville town (21 records), Ravenel town (16 records), Folly Beach city (12 records), Hollywood town (12 records), Lincolnville town (10 records), Mount Pleasant town (10 records), Isle of Palms city (8 records), Awendaw town (7 records); and 3 more jurisdictions (see the Excel file). | Speeds under 20 kt (likely entry errors) are left out of the observed range. |
| Tornado | Enhanced Fujita (Fujita before Feb 2007) | 61 records, 1957 to 2024 | F/EF0 to F/EF3 (median between F/EF0 and F/EF1); 60 with a recorded value | F3 tornado, 1960-09-11, 8.8 mi path length (whole path, pre-1996), 100 yd wide, $2,500,000 property; crops not recorded (1960 dollars), 10 direct injuries | Event records naming jurisdictions in the plan: Rockville town (6 records), Charleston city (4 records), Isle of Palms city (4 records), Awendaw town (3 records), Lincolnville town (1 record), Ravenel town (1 record). | Before 1996 a tornado is listed once, under the county where it began, with its whole path's rating and length; from 1996 on, each county lists its own segment. Length is not used to rank tornadoes (see Methods). | |
| Tsunami | none (count and damage only) | 0 | Physical measure: in event narratives only (local data needed). | ||||
| Wildfire | acres burned (local data) | 4 records, 2011 to 2025 (4 zone-level) | Wildfire, 2011-03-23, $2,000,000 property; $0 crops (2011 dollars); NWS zone SCZ050 | Countywide (zone-level records). | Acres burned: in event narratives only (local data needed). | ||
| Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleet | none in data (snowfall: local data) | 12 records, 2000 to 2026 (12 zone-level) | Heavy Snow, 2010-02-12, $50,000 property; $0 crops (2010 dollars); NWS zone SCZ050 | Countywide (zone-level records). | Snow depth: in event narratives only (local data needed). |
Where a hazard names more than 10 jurisdictions, the table lists the 10 with the most records; every one is in the Excel file, sheet "B1-c Extent".
Storm Events records are more complete after 1996; before 1996 only Tornado (from 1950), Hail and Thunderstorm Wind (from 1955) exist. Zone-level records whose zone no NWS zone-county file places in this county (mostly before 2020) are not counted here (the Methods page explains the zone matching).
Dollars are nominal (as reported), labeled with the year; not adjusted for inflation.
A monthly summary record covers most or all of a month; it does not count days at wave conditions.
Supports FEMA checklist item B1-d: previous occurrences
Federal declarations for this county: 27 declarations covering 17 separate hazard incidents counted in this packet (declarations for the same incident count once; non-natural and evacuation-only declarations are not counted).
Federal disaster declarations for this county
Sources: 1, 2, 3
| Declared | Incident began | FEMA number | Type | Title | Mapped hazard | County Public Assistancefederal share obligated, nominal dollars | Flags | Notes |
|---|---|---|---|---|---|---|---|---|
| 2026-01-23 | 2026-01-21 | EM-3632-SC | Emergency | Severe Winter Storm | Winter Weather | no Public Assistance recorded | new since last plan; within last 5 years | |
| 2024-09-26 | 2024-09-25 | EM-3619-SC | Emergency | Hurricane Helene | Hurricane (primary); also designated: Inland Flooding, Landslide, Tornado | no Public Assistance recorded | new since last plan; within last 5 years | |
| 2024-08-05 | 2024-08-04 | EM-3606-SC | Emergency | Hurricane Debby | Hurricane (primary); also designated: Inland Flooding | $17,716.50 | new since last plan; within last 5 years | |
| 2023-08-31 | 2023-08-29 | EM-3597-SC | Emergency | Hurricane Idalia | Hurricane (primary); also designated: Inland Flooding | $446,842.63 | in the 12 months before plan approval; within last 5 years | |
| 2022-11-21 | 2022-09-25 | DR-4677-SC | Major disaster | Hurricane Ian | Hurricane | $3,680,870.70 | within last 5 years | |
| 2022-09-29 | 2022-09-25 | EM-3585-SC | Emergency | Hurricane Ian | Hurricane | no Public Assistance recorded | within last 5 years | same incident as DR-4677 |
| 2020-03-27 | 2020-01-20 | DR-4492-SC | Major disaster | COVID-19 Pandemic | Non-natural, not counted | $116,433,378.41 | ||
| 2020-03-13 | 2020-01-20 | EM-3470-SC | Emergency | COVID-19 | Non-natural, not counted | no Public Assistance recorded | same incident as DR-4492 | |
| 2019-09-30 | 2019-08-31 | DR-4464-SC | Major disaster | Hurricane Dorian | Hurricane | $14,384,265.88 | ||
| 2019-09-01 | 2019-08-31 | EM-3421-SC | Emergency | Hurricane Dorian | Hurricane | no Public Assistance recorded | same incident as DR-4464 | |
| 2018-09-16 | 2018-09-08 | DR-4394-SC | Major disaster | Hurricane Florence | Hurricane | $1,952,087.51 | ||
| 2018-09-10 | 2018-09-08 | EM-3400-SC | Emergency | Hurricane Florence | Hurricane | no Public Assistance recorded | same incident as DR-4394 | |
| 2017-10-16 | 2017-09-06 | DR-4346-SC | Major disaster | Hurricane Irma | Hurricane | $8,453,784.21 | ||
| 2017-09-07 | 2017-09-06 | EM-3386-SC | Emergency | Hurricane Irma | Hurricane | no Public Assistance recorded | same incident as DR-4346 | |
| 2016-10-11 | 2016-10-04 | DR-4286-SC | Major disaster | Hurricane Matthew | Hurricane | $18,842,788.04 | ||
| 2016-10-06 | 2016-10-04 | EM-3378-SC | Emergency | Hurricane Matthew | Hurricane | no Public Assistance recorded | same incident as DR-4286 | |
| 2015-10-05 | 2015-10-01 | DR-4241-SC | Major disaster | Severe Storms and Flooding | Inland Flooding | $4,574,641.95 | ||
| 2015-10-03 | 2015-10-01 | EM-3373-SC | Emergency | Severe Storms and Flooding | Inland Flooding | no Public Assistance recorded | same incident as DR-4241 | |
| 2014-02-12 | 2014-02-10 | EM-3369-SC | Emergency | Severe Winter Storm | Ice Storm | no Public Assistance recorded | ||
| 2005-09-10 | 2005-08-29 | EM-3233-SC | Emergency | Hurricane Katrina Evacuation | Hurricane: evacuation support, not a local hazard event; not counted | $49,603.08 | ||
| 2004-10-07 | 2004-09-06 | DR-1566-SC | Major disaster | Tropical Storm Frances | Hurricane | PA not declared for this county | ||
| 2004-09-15 | 2004-08-28 | DR-1547-SC | Major disaster | Tropical Storm Gaston | Hurricane | $1,918,486.80 | ||
| 2000-01-31 | 2000-01-22 | DR-1313-SC | Major disaster | Severe Winter Storm | Winter Weather | no Public Assistance recorded | ||
| 1999-09-21 | 1999-09-14 | DR-1299-SC | Major disaster | Hurricane Floyd Major Disaster Declarations | Hurricane | $3,971,342.82 | ||
| 1999-09-15 | 1999-09-14 | EM-3145-SC | Emergency | Hurricane Floyd Emergency Declarations | Hurricane | no Public Assistance recorded | same incident as DR-1299 | |
| 1989-09-22 | 1989-09-21 | DR-843-SC | Major disaster | Hurricane Hugo | Hurricane | no Public Assistance recorded | ||
| 1977-08-04 | 1977-08-04 | EM-3047-SC | Emergency | Drought | Drought | no Public Assistance recorded |
School districts and special districts in this county: $3,945,468.06 (included in the county total above). Public Assistance matched by applicant name to the school districts and special districts FEMA lists as plan participants in this county. They have no row of their own in the jurisdiction table, so their total is listed here. These dollars are already included in the county PA column of the declarations table (the FEMA record places each applicant in this county), so this line is not added to it.
County Public Assistance: applicants the FEMA record places in this county, including any state agencies FEMA files there; statewide rows are listed on the state page; federal share obligated, nominal dollars.
Statewide declarations
Source: 2
| Declared | Incident began | FEMA number | Type | Title | Mapped hazard |
|---|---|---|---|---|---|
| 1955-08-20 | 1955-08-20 | DR-44-SC | Major disaster | Hurricanes | Hurricane (primary); also designated: Inland Flooding |
| 1954-10-17 | 1954-10-17 | DR-29-SC | Major disaster | Hurricane | Hurricane (primary); also designated: Inland Flooding |
FEMA recorded these with designated area Statewide and no county, so they are listed on every county page in the state and not counted with county rows. Local data needed: whether each one affected this county.
Public Assistance filed under this county for declarations that do not list it: 1 row, $63,419.59
Sources: 2, 3
| FEMA number | Declared | Title | Applicant | PA obligatedfederal share obligated, nominal dollars |
|---|---|---|---|---|
| DR-4166-SC | 2014-03-12 | Severe Winter Storm | North Charleston, City of | $63,419.59 |
FEMA's Public Assistance summaries file these applicants under this county, but FEMA's declaration rows for these disasters do not designate it (an electric cooperative or district serving several counties, for example). Not in any declaration row above and not counted.
Previous occurrences by hazard, with explicit no-event rows
Sources: 2, 6, 7
| Hazard | Storm Events records, all years on file(years in the Period column) | Since plan approvalrecords | In the 12 months before plan approvalrecords | Last 5 yearsrecords | Declared incidents, all yearsseparate disasters | Declared since approvalseparate disasters | Period | Statement |
|---|---|---|---|---|---|---|---|---|
| Coastal Flooding | 85 | 5 | 5 | 17 | 0 | 0 | 1996 to 2026-06-30 | |
| Cold Wave | 6 | 3 | 0 | 4 | 0 | 0 | 1996 to 2026-06-30 | Includes 2 Frost/Freeze records. |
| Drought | 20 | 0 | 0 | 0 | 1 | 0 | 1996 to 2026-06-30 | |
| Earthquake | 0 | 0 | 0 | 0 | 0 | 0 | Storm Events does not record earthquakes; the USGS earthquake catalog is the source. | |
| Hail | 300 | 3 | 4 | 14 | 0 | 0 | 1955 to 2026-06-30 | |
| Heat Wave | 19 | 0 | 0 | 0 | 0 | 0 | 1996 to 2026-06-30 | |
| Hurricane | 36 | 2 | 1 | 4 | 12 | 2 | 1996 to 2026-06-30 | Includes 4 Tropical Depression records. |
| Ice Storm | 4 | 0 | 0 | 0 | 1 | 0 | 1996 to 2026-06-30 | |
| Inland Flooding | 311 | 68 | 11 | 84 | 4 | 2 | 1996 to 2026-06-30 | |
| Landslide | 0 | 0 | 0 | 0 | 1 | 1 | 1996 to 2026-06-30 | No Storm Events records of this type; 1 federal declared incident (see declarations table) |
| Lightning | 47 | 4 | 0 | 10 | 0 | 0 | 1996 to 2026-06-30 | |
| Strong Wind | 677 | 31 | 26 | 89 | 0 | 0 | 1955 to 2026-06-30 | Includes 10 High Wind and 43 Strong Wind records. |
| Tornado | 61 | 9 | 1 | 11 | 1 | 1 | 1950 to 2026-06-30 | |
| Tsunami | 0 | 0 | 0 | 0 | 0 | 0 | 1996 to 2026-06-30 | No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events |
| Wildfire | 4 | 1 | 0 | 2 | 0 | 0 | 1996 to 2026-06-30 | |
| Winter Weather | 12 | 5 | 0 | 7 | 2 | 1 | 1996 to 2026-06-30 |
Notable Storm Events records
Sources: 1, 6, 7
| Date | Event type | Magnitude or extent | Damagenominal dollars | Deaths, injuriesdirect only | Location | Flags | Why listed |
|---|---|---|---|---|---|---|---|
| 2024-01-09 | High Wind | 60 kt (69 mph) measured gust | property not reported; $0 crops, reported for the zone (2024 dollars) | 0, 0 | NWS zone SCZ050 (CHARLESTON), zone-level | in the 12 months before plan approval; within last 5 years | B1-c worst recorded: High Wind and Strong Wind |
| 2023-12-17 | Flash Flood | $0 property; $0 crops (2023 dollars) | 1, 0 | SNOWDEN | in the 12 months before plan approval; within last 5 years | deaths or injuries recorded | |
| 2022-04-05 | Thunderstorm Wind | 83 kt (96 mph) estimated gust | damage not reported | 0, 0 | RANTOWLES to MORRIS ACRES | within last 5 years | B1-c worst recorded: Thunderstorm Wind |
| 2012-08-28 | Flash Flood | $750,000 property; $0 crops (2012 dollars) | 0, 0 | CHARLESTON | B1-c worst recorded: Flash Flood, Flood, Lakeshore Flood | ||
| 2011-03-23 | Wildfire | $2,000,000 property; $0 crops, reported for the zone (2011 dollars) | 0, 0 | NWS zone SCZ050 (CHARLESTON), zone-level | B1-c worst recorded: Wildfire | ||
| 2011-01-10 | Ice Storm | $150,000 property; $0 crops, reported for the zone (2011 dollars) | 0, 0 | NWS zone SCZ050 (CHARLESTON), zone-level | B1-c worst recorded: Ice Storm | ||
| 2009-06-22 | Coastal Flood | $100,000 property; crops not reported, reported for the zone (2009 dollars) | 0, 0 | NWS zone SCZ050 (CHARLESTON), zone-level | B1-c worst recorded: Coastal Flood, Storm Surge/Tide | ||
| 2008-04-15 | Strong Wind | 40 kt (46 mph) estimated gust | $5,000 property; $0 crops, reported for the zone (2008 dollars) | 2, 2 | NWS zone SCZ050 (CHARLESTON), zone-level | deaths or injuries recorded | |
| 1999-08-01 | Heat | damage not reported | 6, 0 | NWS zone SCZ050 (CHARLESTON), zone-level | deaths or injuries recorded | ||
| 1996-07-12 | Hurricane (Typhoon), NOAA's event type name | damage not reported | 0, 0 | NWS zone SCZ050 (CHARLESTON), zone-level | B1-c worst recorded: Hurricane, Tropical Storm, Tropical Depression | ||
| 1996-02-03 | Cold/Wind Chill | damage not reported | 1, 0 | NWS zone SCZ050 (CHARLESTON), zone-level | B1-c worst recorded: Cold/Wind Chill, Extreme Cold/Wind Chill | ||
| 1960-09-11 | Tornado | F3, 8.8 mi path length (whole path, pre-1996), 100 yd wide | $2,500,000 property; crops not recorded (1960 dollars) | 0, 10 | location not recorded | B1-c worst recorded: Tornado |
The full list is in the Excel file, sheet "B1-d Storm Events history" (1,582 rows).
Location is the place NOAA recorded, as written in its data; it need not be a jurisdiction in this plan.
Local data needed: state-declared emergencies, from your state emergency management agency (federal data do not include them).
Tribal and special-area declarations in this state are listed on the state page.
Supports FEMA checklist item B1-e: probability of future events
Probability: FEMA annualized frequency and descriptor per hazard
Sources: 5, 6
| Hazard | FEMA annualized frequency (modeled)unit per row | Unit | In plain terms | Descriptor | Descriptor basis | NRI events or days in its record period (hail, wind and tornado are area-weighted, so can be fractional) | NRI period | Location | Note |
|---|---|---|---|---|---|---|---|---|---|
| Coastal Flooding | 3.65 | events per year at a location (modeled) | about 3.6 per year at a given location in the county | Highly likely | FEMA annualized frequency (modeled) | not shown | modeled | see B1-f | Descriptor from NRI: the rate at a location is 1 or more a year, so the county rate is at least that. |
| Cold Wave | 0.79 | event-days per year | about 0.79 days per year | Possible (from Storm Events: 2 of 30 years) | event-days in 2 of 30 years, 1996 to 2025 (6.67%) | 15 | 2005-11-12 to 2024-11-12 (19 years) | countywide | |
| Drought | 15.3 | event-days per year | about 15.3 days per year | Likely (from Storm Events: 5 of 30 years) | event-days in 5 of 30 years, 1996 to 2025 (16.7%) | 546 | 2000 to 2025 (25.25 years; D3 and D4 only) | countywide | |
| Earthquake | 0.00629 | annual probability at a location | chance a given location in the county has at least minor-damage shaking in a year: 0.629% | not shown | modeled | see B1-f | No descriptor (Storm Events does not record earthquakes). | ||
| Hail | 2.2 | events per year | about 2.2 per year | Highly likely | FEMA annualized frequency (modeled) | 92.8 (modeled) | 1986 to 2023 (38 years) | countywide | |
| Heat Wave | 9.58 | event-days per year | about 9.58 days per year | Likely (from Storm Events: 10 of 30 years) | event-days in 10 of 30 years, 1996 to 2025 (33.3%) | 161 | 2005-11-12 to 2024-11-12 (19 years) | countywide | |
| Hurricane | 0.338 | events per year | about 1 in 3 years | Likely | FEMA annualized frequency (modeled) | 126 | 1851 to 2024 (Atlantic) | see B1-f | NRI counts hurricane and tropical storm tracks passing within storm-force wind range; federal declarations are in B1-d. |
| Ice Storm | 0.879 | event-days per year | about 0.879 days per year | Likely (from Storm Events: 3 of 30 years) | event-days in 3 of 30 years, 1996 to 2025 (10%) | 47 | 1946-12-31 to 2014-02-12 (67 years) | countywide | |
| Inland Flooding | 3.54 | event-days per year | about 3.54 days per year | Highly likely (from Storm Events: 27 of 30 years) | event-days in 27 of 30 years, 1996 to 2025 (90%) | 99 | 1996 to 2023 (28 years) | see B1-f | |
| Landslide | 0.205 | events per year (modeled) | about 1 in 5 years | Likely | FEMA annualized frequency (modeled) | not shown | modeled | see B1-f | |
| Lightning | 63.3 | days per year with a strike | about 63.3 days per year | Highly likely | FEMA annualized frequency (modeled) | not shown | 1995 to 2023 (29 years; CONUS) | countywide | |
| Strong Wind | 1.6 | events per year | about 1.6 per year | Highly likely | FEMA annualized frequency (modeled) | 48 | 1986 to 2023 (38 years) | countywide | |
| Tornado | 0.491 | events per year | about 1 in 2 years | Likely | FEMA annualized frequency (modeled) | not shown | 1950 to 2023 (EF2+); 1986 to 2023 (EF0-1) | see B1-f | |
| Tsunami | annual probability at the most exposed location (used in place of a county value) | Storm Events records in 0 of 30 years, 1996 to 2025 (0%) | not shown | modeled | see B1-f | No descriptor: no Storm Events record 1996 to 2025 | |||
| Wildfire | 0.00226 | annual probability at a location | chance a given location in the county burns in a year: 0.226% | Likely (from Storm Events: 4 of 30 years) | Storm Events records in 4 of 30 years, 1996 to 2025 (13.3%) | not shown | modeled | see B1-f | Descriptor from Storm Events, not NRI. |
| Winter Weather | 0.948 | event-days per year | about 0.948 days per year | Likely (from Storm Events: 6 of 30 years) | event-days in 6 of 30 years, 1996 to 2025 (20%) | 18 | 2005-11-12 to 2024-11-12 (19 years) | countywide |
FEMA annualized frequency (modeled) is the National Risk Index v1.20 (December 2025) estimate of how often a hazard affects this county in a year; it is not recorded events divided by years, and its unit differs by hazard (events, event-days, or days with a lightning strike per year). For earthquake, wildfire, coastal flooding and tsunami the value is the chance (or number of events) at a location in the county, not across the county, so no "1 in N years" is given and the descriptor comes from Storm Events where it has a record (none for earthquake). The Methods page gives each hazard's method, from FEMA's National Risk Index Technical Documentation v1.20.
Where NRI gives event-days, the descriptor comes from the share of years with a Storm Events record; NRI's source records more events, so the two differ.
Descriptor scale used in this packet (defined per unit)
Sources: 5, 6
| Unit | Descriptor | Definition |
|---|---|---|
| events per year | Highly likely | 1 or more per year |
| events per year | Likely | about once in 1 to 10 years |
| events per year | Possible | about once in 10 to 100 years |
| events per year | Unlikely | less than once in 100 years |
| annual probability | Likely | 10% to under 100% chance in a given year |
| annual probability | Possible | 1% to under 10% chance in a given year |
| annual probability | Unlikely | under 1% chance in a given year |
| event-days (share of years) | Highly likely | event-days recorded in 90% or more of years |
| event-days (share of years) | Likely | event-days recorded in 10% to under 90% of years |
| event-days (share of years) | Possible | event-days recorded in some years but under 10% of years |
| lightning strike-days | Highly likely | cloud-to-ground strikes on 1 or more days per year |
Intensity bands: historical frequency (Storm Events)
Source: 6
| Hazard | Band | Years | Eventscounty-coded records | Years in period | Events per yearevents / years |
|---|---|---|---|---|---|
| Hail | 1.00-1.99 in | 1996 to 2025 | 147 | 30 | 4.9 |
| Hail | 2.00 in+ | 1996 to 2025 | 3 | 30 | 0.1 |
| Thunderstorm Wind (counted as NRI Strong Wind) | 50-64 kt | 1996 to 2025 | 465 | 30 | 15.5 |
| Thunderstorm Wind (counted as NRI Strong Wind) | 65 kt+ | 1996 to 2025 | 15 | 30 | 0.5 |
| Thunderstorm Wind (counted as NRI Strong Wind) | unmeasured or below 50 kt | 1996 to 2025 | 36 | 30 | 1.2 |
| Tornado | EF0-1 | 1996 to 2025 | 41 | 30 | 1.37 |
| Tornado | EF2-3 | 1996 to 2025 | 2 | 30 | 0.0667 |
| Tornado | EF4-5 | 1996 to 2025 | 0 | 30 | 0 |
| Tornado | unrated (EFU) | 1996 to 2025 | 0 | 30 | 0 |
The bands show how often events of each severity were recorded in this county, to profile how severe events have been (FEMA's probability item asks for the range of intensities).
Hail smaller than 1 inch is not counted: on 2010-01-05 the National Weather Service raised its severe-hail threshold from 3/4 inch to 1 inch, so smaller reports became less common after 2009 (NWS Service Change Notice 09-52). NRI hail frequency uses a 0.75 inch threshold.
Optional: future conditions. Not a required item in the 2025 FEMA Local Mitigation Planning Policy Guide; some states ask for it. The federal Climate Mapping for Resilience and Adaptation (CMRA) site gives county exposure to future climate conditions (https://resilience.climate.gov/).
Supports FEMA checklist item B1-f: hazards that vary across jurisdictions
Range of census tract risk within the county
Source: 5
| Hazard | Tractsrated of all | NRI risk score, 0 to 100 | Tracts by rating | ||
|---|---|---|---|---|---|
| Min | Median | Max | |||
| Coastal Flooding | 94 of 98 | 69.7 | 97.2 | 100.0 | Very High 12, Relatively High 49, Relatively Moderate 19, Relatively Low 11, Very Low 3, No Rating 4 |
| Cold Wave | 98 of 98 | 24.2 | 50.4 | 78.7 | Relatively High 2, Relatively Moderate 59, Relatively Low 37 |
| Drought | 21 of 98 | 66.8 | 77.5 | 89.3 | Relatively Low 9, Very Low 12, No Rating 77 |
| Earthquake | 98 of 98 | 79.5 | 88.9 | 99.2 | Very High 10, Relatively High 42, Relatively Moderate 46 |
| Hail | 98 of 98 | 20.1 | 38.3 | 63.8 | Relatively Low 54, Very Low 44 |
| Heat Wave | 98 of 98 | 4.0 | 22.2 | 59.4 | Relatively Moderate 4, Relatively Low 68, Very Low 26 |
| Hurricane | 98 of 98 | 91.6 | 98.0 | 99.9 | Very High 71, Relatively High 27 |
| Ice Storm | 98 of 98 | 43.7 | 75.9 | 91.9 | Relatively High 5, Relatively Moderate 72, Relatively Low 21 |
| Inland Flooding | 98 of 98 | 1.2 | 22.1 | 86.7 | Relatively High 2, Relatively Moderate 18, Relatively Low 47, Very Low 31 |
| Landslide | 74 of 98 | 12.3 | 45.9 | 78.5 | Very Low 74, No Rating 24 |
| Lightning | 98 of 98 | 18.7 | 53.7 | 87.6 | Relatively High 11, Relatively Moderate 49, Relatively Low 37, Very Low 1 |
| Strong Wind | 98 of 98 | 16.0 | 42.6 | 89.8 | Relatively High 1, Relatively Moderate 18, Relatively Low 76, Very Low 3 |
| Tornado | 98 of 98 | 15.9 | 33.6 | 61.4 | Relatively Moderate 1, Relatively Low 76, Very Low 21 |
| Tsunami | 0 of 98 | Insufficient Data 98 | |||
| Wildfire | 89 of 98 | 19.9 | 84.6 | 97.4 | Relatively High 1, Relatively Moderate 31, Relatively Low 37, Very Low 20, No Rating 9 |
| Winter Weather | 98 of 98 | 27.2 | 48.9 | 74.2 | Relatively Moderate 53, Relatively Low 45 |
Drought: Agriculture is all of NRI's expected annual loss for this hazard in the county, so the tract range mostly reflects where crop and livestock value is.
Rated tracts only: No Rating (score 0.0), Not Applicable and Insufficient Data tracts are counted but not used for the minimum, median and maximum.
The score ranks a tract against all U.S. tracts (100 = highest). The rating is FEMA's category for the tract's risk value, computed differently, so the two can disagree.
Frequency data for cold wave, drought, hail, heat wave, ice storm, lightning, strong wind and winter weather are county-wide or coarse (49 km grid or NWS zone), the same for every jurisdiction; the tract range mostly reflects where buildings and people are (crop and livestock value where a line above names agriculture).
Each jurisdiction (starting figures from federal data)
Sources: 1, 3, 4, 6
| Jurisdiction | Type | Plan status | Repetitive lossFMA RL and SRL (44 CFR 77.2); repeat-flood, any definition | Public Assistance to this jurisdictionFEMA records matched by applicant name; federal share obligated, nominal dollars | Event records naming this placeall years; since its plan | Notes |
|---|---|---|---|---|---|---|
| Charleston County (unincorporated area) | Unincorporated | Approved, expires 2029-03-19 | FMA RL 10, SRL 35; any 206 | $25,620,481.21 | 0 total; 0 since its plan | |
| Awendaw town | Town | Approved, expires 2029-03-19 | FMA RL 0, SRL 0; any 1 | $2,589.58 | 29 total; 2 since its plan | |
| Charleston city | City | Approved, expires 2029-03-19 | FMA RL 53, SRL 144; any 753 | $9,019,120.03 | 143 total; 24 since its plan | Whole community, including 2 properties with no county in FEMA's file; in-county portion (county table): FMA RL 53, FMA SRL 144, NFIP RL 709, NFIP SRL 99, any category 751. Includes $81,057.22 for declarations not counted as hazard incidents (DR-4492-SC, EM-3233-SC). |
| Folly Beach city | City | Approved, expires 2029-03-19 | FMA RL 1, SRL 10; any 50 | $676,352.01 | 20 total; 1 since its plan | |
| Hollywood town | Town | Approved, expires 2029-03-19 | FMA RL 0, SRL 0; any 4 | $288,752.88 | 16 total; 0 since its plan | |
| Isle of Palms city | City | Approved, expires 2029-03-19 | FMA RL 0, SRL 8; any 53 | $4,360,907.48 | 17 total; 1 since its plan | Includes $9,040.47 for declarations not counted as hazard incidents (DR-4492-SC). |
| James Island town | Town | Approved, expires 2029-03-19 | FMA RL 0, SRL 1; any 19 | $18,717.51 | 1 total; 0 since its plan | |
| Kiawah Island town | Town | Approved, expires 2029-03-19 | FMA RL 0, SRL 1; any 14 | $412,577.14 | 0 total; 0 since its plan | |
| Lincolnville town | Town | Approved, expires 2029-03-19 | FMA RL 0, SRL 0; any 0 | $14,186.70 | 14 total; 2 since its plan | |
| McClellanville town | Town | Approved, expires 2029-03-19 | FMA RL 0, SRL 0; any 1 | $3,720 | 1 total; 0 since its plan | |
| Meggett town | Town | Approved, expires 2029-03-19 | FMA RL 0, SRL 0; any 2 | $45,391.12 | 4 total; 0 since its plan | |
| Mount Pleasant town | Town | Approved, expires 2029-03-19 | FMA RL 1, SRL 9; any 60 | $5,378,958.66 | 30 total; 2 since its plan | Also approved under plan 109525 (Mount Pleasant, expires 2029-02-20). FEMA's plan status map shows one plan per jurisdiction and may show one of these; this packet uses the approved plan that expires last. Includes $18,574.41 for declarations not counted as hazard incidents (DR-4492-SC). |
| North Charleston city | City | Approved, expires 2029-03-19 | FMA RL 14, SRL 18; any 97 | $3,926,346.96 | 46 total; 0 since its plan | Whole community, including the part in Dorchester County; in-county portion (county table): FMA RL 14, FMA SRL 18, NFIP RL 94, NFIP SRL 19, any category 94. Includes $145,454.38 for declarations not counted as hazard incidents (DR-4492-SC, EM-3233-SC). |
| Ravenel town | Town | Approved, expires 2029-03-19 | FMA RL 0, SRL 0; any 0 | no Public Assistance recorded | 24 total; 0 since its plan | |
| Rockville town | Town | Approved, expires 2029-03-19 | FMA RL 0, SRL 0; any 0 | no Public Assistance recorded | 32 total; 3 since its plan | |
| Seabrook Island town | Town | Approved, expires 2029-03-19 | FMA RL 0, SRL 0; any 14 | $196,435.11 | 0 total; 0 since its plan | |
| Sullivan's Island town | Town | Approved, expires 2029-03-19 | FMA RL 0, SRL 2; any 27 | $276,129.51 | 0 total; 0 since its plan | Includes $20,322.15 for declarations not counted as hazard incidents (DR-4492-SC). |
| Summerville town | Town | Expired on 2026-07-06 | FMA RL 5, SRL 1; any 17 | no Public Assistance recorded | 0 total; 0 since its plan | Whole community, including the part in Dorchester County; none of its repeat-flood properties are in this county. |
Repetitive-loss counts are for whole NFIP communities, which can extend beyond this county (see the note in B2-c).
School districts and special districts get a plan clock row only.
County Public Assistance in B1-d also includes applicants filed under the county that are not jurisdictions in this plan (for example state agencies, special districts and nonprofits), so the jurisdiction rows add up to less.
Supports FEMA checklist items B2-a and B2-b: vulnerability and potential impacts
Local data needed
The table below gives county-level starting figures; the plan describes impacts for each jurisdiction and its own assets.
- Critical facilities and lifelines per hazard
- A problem statement per jurisdiction per hazard
- Changes in development in hazard-prone areas since the last approval, or a statement of none (E1-a)
- Future assets
County-level starter: exposure, expected annual loss and damage since the plan
Sources: 1, 2, 3, 5, 6, 7
| Hazard | Building exposuremodeled dollars | Agriculture exposuremodeled dollars | Population exposedpeople | EAL buildingsmodeled dollars per year | EAL agriculturemodeled dollars per year | Cost of expected deaths and injuriesFEMA's dollar value per year, not property damage | EAL as % of exposurebuildings; agriculture where noted | Storm Events damage since 2024-03-20county-coded records, property plus crops, nominal dollars | Zone-level damage since planproperty plus crops, reported for the zone | Public Assistance since plannominal dollars; see note | Note |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Coastal Flooding | $56,286,279,045 | n/a | 217,192 | $31,731,585 | n/a | $3,902,587 | 0.0564% | $0 | |||
| Cold Wave | $96,535,065,240 | $28,818,205 | 407,722 | $53,389 | $17,708 | $6,523,611 | under 0.0001% | $0 | |||
| Drought | n/a | $19,257,704 | n/a | n/a | $50,004 | n/a | 0.26% (agriculture) | NRI has no building exposure for this hazard; agriculture shown | |||
| Earthquake | $163,834,022,184 | n/a | 408,235 | $68,175,993 | n/a | $49,816,994 | 0.0416% | ||||
| Hail | $96,535,065,240 | $28,818,205 | 407,722 | $33,841 | $727 | $416,771 | under 0.0001% | $0 | |||
| Heat Wave | $96,535,065,240 | $28,818,205 | 407,722 | $625 | $75 | $2,034,056 | under 0.0001% | ||||
| Hurricane | $96,527,428,083 | $28,818,205 | 407,701 | $263,973,600 | $428,384 | $16,931,164 | 0.273% | $177,000 | $17,716.50 | ||
| Ice Storm | $96,399,559,222 | n/a | 407,508 | $1,538,417 | n/a | $213,453 | 0.0016% | ||||
| Inland Flooding | $96,433,017,460 | $8,692,211 | 118,923 | $42,615,234 | $406,115 | $1,188,544 | n/a (see note) | $0 | $17,716.50 | NRI counts the full building value of any census block with some flood loss; this is not the value of buildings in the floodplain. Use local FIRM overlays for B2-a/B2-b. | |
| Landslide | $73,189,773 | n/a | 237 | $649 | n/a | $1 | 0.000887% | no Public Assistance recorded (1 declaration) | |||
| Lightning | $96,535,065,240 | n/a | 407,722 | $86,270 | n/a | $1,570,620 | under 0.0001% | $29,000 | |||
| Strong Wind | $96,535,065,240 | $28,818,205 | 407,722 | $51,576 | $154 | $1,638,459 | under 0.0001% | $63,000 | |||
| Tornado | $96,535,065,240 | $28,818,205 | 407,722 | $767,451 | $474 | $2,251,337 | 0.000795% | $0 | no Public Assistance recorded (1 declaration) | ||
| Tsunami | n/a | n/a | n/a | n/a | n/a | n/a | NRI publishes no building exposure for this county | ||||
| Wildfire | $17,025,121,268 | $16,877,791 | 96,339 | $2,832,936 | $296 | $244,626 | 0.0166% | ||||
| Winter Weather | $96,535,065,240 | $28,818,205 | 407,722 | $91,917 | $15 | $209,072 | under 0.0001% | $0 | no Public Assistance recorded (1 declaration) |
Totals since 2024-03-20 (Storm Events through 2026-06-30): 114 county-coded records, 93 with a damage value recorded (including $0), $92,000; 17 zone-level records, 11 with a damage value recorded (including $0), $177,000 reported for the zone; Public Assistance: $17,716.50 on 3 counted declarations, 1 of them with Public Assistance.
FEMA does not split Public Assistance by hazard. A declaration mapped to several hazards is listed under each of them with its full amount, so the per-hazard column does not add up to the total; the unit total counts each declaration once.
NRI computes earthquake exposure on its own basis, so it exceeds the county building value in B2-a.
Supports FEMA checklist item B2-a: vulnerability (county context)
County context
Source: 5
| Measure | Value |
|---|---|
| Population | 407,722 |
| Building value (total, not at risk) | $96,535,065,240 |
| Agriculture value (total, not at risk) | $28,818,205 |
| NRI risk rating (all hazards) | Relatively High |
| Expected annual loss, buildings and agriculture, all hazards | $412,857,434 |
| Expected annual loss, population equivalence, all hazards (NRI values each statistical life at $13.7M; a modeled value of expected deaths and injuries, not property damage) | $86,941,295 |
| Social vulnerability rating | Relatively Low |
| Community resilience rating | Very High |
| NRI version | December 2025 |
FEMA's all-hazard expected annual loss adds buildings, agriculture and population equivalence; this table gives the property part and the population-equivalence part as separate rows.
Social vulnerability: higher means people are more likely to be harmed and slower to recover. Community resilience: lower means the community is less able to recover. High social vulnerability and low resilience both raise the NRI risk rating.
Supports FEMA checklist item B2-c: repetitive loss properties
Repetitive loss in this county, both definitions
Sources: 1, 4
| Definition | Properties | Severe repetitive loss | Properties |
|---|---|---|---|
| Repetitive loss, FMA definition (44 CFR 77.2) | 79 | Severe repetitive loss, FMA definition (44 CFR 77.2) | 228 |
| Repetitive loss, NFIP insurance definition | 1,245 | Severe repetitive loss, NFIP insurance definition | 177 |
The state NFIP coordinator's list, the source FEMA's Handbook names, often uses the NFIP insurance definition (second row).
Repeat-flood properties: county and state-level rows
Sources: 1, 4
| Scope | RL, FMAproperties | SRL, FMAproperties | RL, NFIPproperties | SRL, NFIPproperties | Any categoryproperties | Mitigatedproperties | Currently insuredproperties |
|---|---|---|---|---|---|---|---|
| County total | 79 | 228 | 1,245 | 177 | 1,296 | 45 | 821 |
| of which: Hollywood town | 0 | 0 | 4 | 0 | 4 | 0 | 3 |
| of which: McClellanville town | 0 | 0 | 1 | 0 | 1 | 0 | 0 |
| of which: Meggett town | 0 | 0 | 2 | 0 | 2 | 0 | 1 |
| of which: North Charleston city | 14 | 18 | 94 | 19 | 94 | 0 | 50 |
| of which: Seabrook Island town | 0 | 0 | 14 | 0 | 14 | 0 | 11 |
| of which: Kiawah Island town | 0 | 1 | 14 | 1 | 14 | 0 | 10 |
| of which: Awendaw town | 0 | 0 | 1 | 0 | 1 | 0 | 1 |
| of which: James Island town | 0 | 1 | 19 | 1 | 19 | 0 | 17 |
| of which: Charleston city | 53 | 144 | 709 | 99 | 751 | 40 | 509 |
| of which: Charleston County (unincorporated area) | 10 | 35 | 204 | 34 | 206 | 1 | 124 |
| of which: Folly Beach city | 1 | 10 | 50 | 10 | 50 | 0 | 16 |
| of which: Isle of Palms city | 0 | 8 | 48 | 4 | 53 | 3 | 33 |
| of which: Mount Pleasant town | 1 | 9 | 59 | 8 | 60 | 1 | 29 |
| of which: Sullivans Island town | 0 | 2 | 26 | 1 | 27 | 0 | 17 |
| Statewide, no county in FEMA's file | 0 | 0 | 2 | 0 | 2 | 0 | 0 |
The statewide row counts properties FEMA's file gives with no county in this state; they are listed for reference and are not in this county's counts.
Repeat-flood properties by jurisdiction in the plan (NFIP community)
Sources: 1, 4
| Jurisdiction | NFIP community ID | RL, FMAproperties | SRL, FMAproperties | RL, NFIPproperties | SRL, NFIPproperties | Any categoryproperties | Mitigatedproperties | Currently insuredproperties | Note |
|---|---|---|---|---|---|---|---|---|---|
| Charleston County (unincorporated area) | 455413 | 10 | 35 | 204 | 34 | 206 | 1 | 124 | |
| Awendaw town | 450262 | 0 | 0 | 1 | 0 | 1 | 0 | 1 | |
| Charleston city | 455412 | 53 | 144 | 711 | 99 | 753 | 40 | 509 | Whole community, including 2 properties with no county in FEMA's file; in-county portion (county table): FMA RL 53, FMA SRL 144, NFIP RL 709, NFIP SRL 99, any category 751. |
| Folly Beach city | 455415 | 1 | 10 | 50 | 10 | 50 | 0 | 16 | |
| Hollywood town | 450037 | 0 | 0 | 4 | 0 | 4 | 0 | 3 | |
| Isle of Palms city | 455416 | 0 | 8 | 48 | 4 | 53 | 3 | 33 | |
| James Island town | 450263 | 0 | 1 | 19 | 1 | 19 | 0 | 17 | |
| Kiawah Island town | 450257 | 0 | 1 | 14 | 1 | 14 | 0 | 10 | |
| Lincolnville town | 450233 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |
| McClellanville town | 450039 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | |
| Meggett town | 450040 | 0 | 0 | 2 | 0 | 2 | 0 | 1 | |
| Mount Pleasant town | 455417 | 1 | 9 | 59 | 8 | 60 | 1 | 29 | |
| North Charleston city | 450042 | 14 | 18 | 97 | 19 | 97 | 0 | 52 | Whole community, including the part in Dorchester County; in-county portion (county table): FMA RL 14, FMA SRL 18, NFIP RL 94, NFIP SRL 19, any category 94. |
| Ravenel town | 450043 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |
| Rockville town | 450249 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |
| Seabrook Island town | 450256 | 0 | 0 | 14 | 0 | 14 | 0 | 11 | |
| Sullivan's Island town | 455418 | 0 | 2 | 26 | 1 | 27 | 0 | 17 | |
| Summerville town | 450073 | 5 | 1 | 17 | 1 | 17 | 0 | 13 | Whole community, including the part in Dorchester County; none of its repeat-flood properties are in this county. |
Counts by occupancy group for each jurisdiction are in the Excel file, sheet "B2-c Jurisdictions".
Jurisdiction rows are whole NFIP communities and need not add up to the county total: a community that extends into another county is counted in full on each jurisdiction row, while the county table counts only its part in this county.
County repeat-flood properties by occupancy group
Sources: 1, 4
| Occupancy group | RL, FMAproperties | SRL, FMAproperties | RL, NFIPproperties | SRL, NFIPproperties | Any categoryproperties | Mitigatedproperties | Currently insuredproperties |
|---|---|---|---|---|---|---|---|
| single-family residential | 74 | 181 | 1,008 | 132 | 1,056 | 43 | 707 |
| 2 to 4 unit residential | 2 | 13 | 83 | 11 | 85 | 2 | 38 |
| other residential | 3 | 18 | 64 | 19 | 64 | 0 | 42 |
| non-residential | 0 | 16 | 90 | 15 | 91 | 0 | 34 |
| not reported | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
FEMA's occupancy groups have no institutional class; institutional properties are counted in non-residential or other residential in the table by occupancy group.
FMA RL and FMA SRL are the Flood Mitigation Assistance definitions (44 CFR 77.2), the ones the FEMA Local Mitigation Planning Policy Guide cites. NFIP repetitive loss (the FEMA insurance definition) is 2 or more claims over $1,000 in 10 years, and a property can leave that group once it is mitigated. Also shown: NFIP severe repetitive loss, any category, mitigated and currently insured. The Methods page gives the OpenFEMA field details.
Counts are aggregates of FEMA's public NFIP Multiple Loss Properties file (FEMA's data date 2026-08-02; file version 2026-08-04). No property is identified. County assignment is FEMA's geocode.
In this county 25 properties are FMA repetitive loss but not NFIP repetitive loss, and 1,191 properties are NFIP repetitive loss but not FMA repetitive loss.
Exact counts; no count suppression.
Sources
Tables cite these sources by number. The full list, for the plan's bibliography (FEMA review item A4-a):
- FEMA, OpenFEMA HazardMitigationPlanStatuses v1, version 2026-09-29T134039Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/HazardMitigationPlanStatuses (API)
- FEMA, OpenFEMA DisasterDeclarationsSummaries v2, version 2026-09-29T162832Z, pulled 2026-09-30, https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries (API)
- FEMA, OpenFEMA PublicAssistanceFundedProjectsSummaries v1, version 2026-09-29T150754Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/PublicAssistanceFundedProjectsSummaries (API)
- FEMA, OpenFEMA NfipMultipleLossProperties v1, version 2026-08-04T164045Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/NfipMultipleLossProperties (API)
- FEMA, FEMA National Risk Index 1.20.0 (December 2025), county and census tract tables, version 1.20.0, pulled 2026-09-30, https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_Counties.zip (download, 25 MB), https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_CensusTracts.zip (download, 635 MB)
- NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-30, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/
- NOAA National Weather Service, NWS county-public forecast zones correlation file, version bp03mr20 to bp16ap26 (11 files; newest bp16ap26), pulled 2026-09-30, https://www.weather.gov/gis/ZoneCounty
- U.S. Census Bureau, Census 2024 Gazetteer, 2020 place by county, CT county-to-cousub crosswalk, version 2024-gazetteer, pulled 2026-09-30, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_counties_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_cousubs_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_place_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_unsd_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_elsd_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_scsd_national.zip, https://www2.census.gov/geo/docs/reference/codes2020/national_place_by_county2020.txt, https://www2.census.gov/geo/docs/reference/ct_change/ct_cou_to_cousub_crosswalk.xlsx (used to match place names and codes; no table prints its values)
What this packet is and what the plan adds
This packet is the federal data for the plan's risk assessment, organized by the items of FEMA's Local Mitigation Plan Review Tool, Element B. Each section heading names the item its tables support; the plan and FEMA's review decide whether the item is met.
The plan adds what only the community has: local data on assets, critical facilities, development and each jurisdiction's impacts; local hazard history, including state-declared emergencies; the mitigation strategy; and adoption.
How the federal data are built: National Risk Index values are FEMA's model, not counts of events. Storm Events is more complete from 1996; zone-level records are placed by forecast zone, not by location in the county. Public Assistance for a jurisdiction is matched by applicant name. The Methods page gives every rule and the known edge cases.
OpenFEMA disclaimer
This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Reuse, citation and corrections
Reuse and citation: Hazard Plain text and tables are licensed under Creative Commons Attribution 4.0 International (CC BY 4.0, https://creativecommons.org/licenses/by/4.0/); credit Hazard Plain and the release. The underlying federal data are public domain; OpenFEMA data are also subject to the OpenFEMA terms and conditions.
Cite this: Hazard Plain (2026). Charleston County, SC: risk-assessment baseline packet, release 2026-10 (data as of 2026-09-30; County FIPS 45019). Automated baseline. https://hazardplain.org/sc/45019/ Built from FEMA OpenFEMA, the FEMA National Risk Index and NOAA NCEI Storm Events; source versions in the packet's Sources list.
Corrections: to report an error, name the packet, the table and what your records show. Contact: [email protected]
Hazard Plain release 2026-10. As of 2026-09-30; Storm Events data through 2026-06-30. Automated baseline.