Hazard Plain Automated baseline

Plaquemines Parish, LA

Risk-assessment baseline packet

County FIPS:
22075
Release:
2026-10
Data as of:
2026-09-30
Storm Events data through:
2026-06-30

Hazard Plain is an independent product built from public federal data. It is not a FEMA document and is not reviewed or endorsed by FEMA or any state agency.

Hazard Plain release 2026-10, as of 2026-09-30.

Summary

Plan status as of 2026-09-30: Approved, expires 2030-06-24. Plan: Plaquemines Parish (FEMA plan 110702), approved 2025-06-25.

Since the plan was approved on 2025-06-25: 1 new hazard declaration (1 incident) and 5 NOAA Storm Events records; details under "What changed since your last plan".

Highest expected annual loss (FEMA National Risk Index, modeled total; see B1-a): Hurricane ($19,105,260 a year), Coastal Flooding ($2,799,811) and Inland Flooding ($2,738,190).

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 2030-06-24
Plan:
Plaquemines Parish (FEMA plan 110702)
Approved:
2025-06-25
Days to expiry:
1,363

What changed since your last plan (approved 2025-06-25)

New federal declarations:
1 new hazard declaration (1 incident): EM-3638-LA (Severe Winter Storm)
Storm Events records since approval:
5 records (data through 2026-06-30)
Repetitive loss now:
FMA RL 225, SRL 175 (44 CFR 77.2); any definition: 475
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

Source: 1

JurisdictionTypeStatusPlanApprovedExpiresDays to expirynegative = days since expiry
Plaquemines ParishCountyApproved, expires 2030-06-24Plaquemines Parish (FEMA plan 110702)2025-06-252030-06-241,363

State plan status and tribal plans in this state: see the state page.

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 EALHazardNRI risk ratingEAL ratingEAL buildingsmodeled dollars per yearEAL agriculturemodeled dollars per yearCost of expected deaths and injuriesFEMA's dollar value per year, not property damageEAL total (see note)modeled dollars per yearStorm Events records, 1996 to 2026-06-30countStorm Events coverage note
1HurricaneRelatively HighRelatively High$18,165,770$158,452$781,038$19,105,26032Includes 1 Tropical Depression record (outside NRI's Hurricane definition).
2Coastal FloodingRelatively HighRelatively High$2,668,920n/a$130,891$2,799,81128
3Inland FloodingVery LowVery Low$2,697,414$18$40,758$2,738,1908
4DroughtRelatively ModerateRelatively Moderaten/a$960,612n/a$960,61211
5TornadoRelatively LowRelatively Low$319,222$198$454,015$773,43519
6Cold WaveRelatively LowRelatively Low$3,108$5,202$700,213$708,5244
7Heat WaveRelatively LowRelatively Low$231$51$588,762$589,04425
8LightningRelatively LowRelatively Low$9,318n/a$206,450$215,7682
9HailVery LowVery Low$86,856$1$9,150$96,00818
10EarthquakeVery LowVery Low$49,164n/a$14,517$63,680Storm Events does not record earthquakes.
11Strong WindVery LowVery Low$9,812$38$18,503$28,35447Includes 2 High Wind records (a NOAA non-thunderstorm wind type, outside NRI's Strong Wind definition).
12Winter WeatherVery LowRelatively Low$3,827$7$8,702$12,5364
13WildfireVery LowVery Low$6,239$7$679$6,9250No recorded events in Storm Events since 1996 (data through 2026-06-30).
14Ice StormVery LowVery Low$4,927n/a$1,600$6,5270Declared 1 time; no Storm Events record of this type.
15LandslideVery LowVery Low$59n/a$3$610No recorded events in Storm Events since 1996 (data through 2026-06-30).
TsunamiInsufficient DataInsufficient Datan/an/an/an/a0No 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 wildfire, 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

HazardHighest-rated census tractsNRI risk rating, score 0 to 100
Earthquaketract 502.02 (Relatively Low, 47.1); tract 502.01 (Very Low, 28.7); tract 504 (Very Low, 25.5)
Hurricanetract 502.02 (Very High, 99.8); tract 502.01 (Very High, 99.4); tract 504 (Very High, 99.1)
Landslidetract 501 (Very Low, 72.8); tract 504 (Very Low, 69.9); tract 508 (Very Low, 61.0)
Tornadotract 502.02 (Relatively High, 78.2); tract 502.01 (Relatively Moderate, 69.8); tract 503 (Relatively Moderate, 68.7)
Tsunamino tract has a National Risk Index rating for this hazard
Wildfiretract 504 (Relatively Low, 78.2); tract 501 (Relatively Low, 70.1); tract 502.02 (Very Low, 58.1)

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 502.02 is Census Tract 502.02). 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

HazardScaleRecordscount and yearsObserved rangeWorst recorded eventMost damaging (when different)How it applies to jurisdictionsNote
Coastal Flood, Storm Surge/Tidenone in data (flood depth: FIRM)28 records, 1996 to 2024 (26 zone-level)Storm Surge/Tide, 2005-08-29, $3,030,000,000 property; crops not reported (2005 dollars); NWS zone LAZ069No event record names a jurisdiction in the plan. Zone-level records (26) apply countywide.Flood depth: see the FEMA Flood Insurance Rate Map.
Cold/Wind Chill, Extreme Cold/Wind Chillwind chill4 records, 1996 to 2025 (4 zone-level)1 day to 10 days (median 4 days); 4 with a recorded value10 consecutive days, 2010-01-02 to 2010-01-11, zone-levelCountywide (zone-level records).
Frost/Freeze (outside NRI's Cold Wave definition)crop damage0
DroughtU.S. Drought Monitor scale (D0 to D4)11 records, 1998 to 2026 (11 zone-level)30 days to 153 days (median 49 days); 4 with a recorded value153 days (5 months), 2023-08-01 to 2023-12-31, a run of 6 consecutive Storm Events drought records, zone-levelDrought, 1998-08-01, property not reported; $250,000 crops (zone total, 1998 dollars)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.
EarthquakeModified Mercalli (local data)0Storm Events does not record earthquakes; the USGS earthquake catalog is the source.
Hailhail size (inches)27 records, 1955 to 20230.75 in to 2 in (median 1.5 in); 27 with a recorded value2 in hail, 2022-05-15; same size also recorded on 1955-06-15, 1956-01-22, 2022-05-15No event record names a jurisdiction in the plan.
Excessive Heat, Heatheat index (in event narratives)25 records, 2010 to 2025 (25 zone-level)1 day to 12 days (median 1 day); 9 with a recorded value12 consecutive days, 2023-08-04 to 2023-08-15, zone-levelCountywide (zone-level records).
Hurricane, Tropical Storm, Tropical DepressionSaffir-Simpson32 records, 1997 to 2024 (32 zone-level)Strongest recorded: Hurricane record (NOAA event type 'Hurricane (Typhoon)'), 2021-08-29 to 2021-08-30, category 3, $100,000,000 property; $0 crops (2021 dollars); NWS zone LAZ063Most damaging recorded: Hurricane (Typhoon), 2005-08-28, $1,520,000,000 property; crops not reported (zone total, 2005 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 StormSperry-Piltz ice scale (local data)0
Flash Flood, Flood, Lakeshore Flooddamage and flood days (flood depth: FIRM)8 records, 1997 to 2011Flash Flood, 2003-06-30, $130,000 property; crops not reported (2003 dollars)No event record names a jurisdiction in the plan.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 Flownone (count and damage only)0
Lightningannualized frequency (the measure FEMA's Local Mitigation Planning Handbook names)2 records, 1998 to 2020Lightning, 2020-08-20, $20,000 property; $0 crops (2020 dollars)No event record names a jurisdiction in the plan.Storm Events lists lightning with damage or casualties.
High Wind and Strong Wind (outside NRI's Strong Wind definition)wind speed (kt and mph)2 records, 1996 to 2019 (2 zone-level)40 kt (46 mph) to 57 kt (66 mph) (median 48.5 kt (56 mph)); 2 with a recorded value57 kt (66 mph) measured gust, High Wind, 2019-10-26; NWS zone LAZ063Countywide (zone-level records).
Thunderstorm Windwind speed (kt and mph)84 records, 1957 to 202650 kt (58 mph) to 87 kt (100 mph) (median 52 kt (60 mph)); 51 with a recorded value87 kt (100 mph) measured gust, Thunderstorm Wind, 2011-03-29Thunderstorm Wind, 1993-08-07, $500,000 property; crops not recorded (1993 dollars)No event record names a jurisdiction in the plan.
TornadoEnhanced Fujita (Fujita before Feb 2007)35 records, 1957 to 2025F/EF0 to F/EF3 (median F/EF1); 33 with a recorded valueF3 tornado, 1957-11-13, 3.6 mi path length (whole path, pre-1996), 200 yd wide, $250 property; crops not recorded (1957 dollars)Tornado, 2025-03-04, $300,000 property; $0 crops (2025 dollars)No event record names a jurisdiction in the plan.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).
Tsunaminone (count and damage only)0
Wildfireacres burned (local data)0
Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleetnone in data (snowfall: local data)4 records, 2004 to 2025 (4 zone-level)No damage reported in 4 records.Countywide (zone-level records).

In event narratives only (local data needed): wind chill, temperature, heat index, ice thickness, acres burned and snow depth; any physical measure of debris flow, lightning and tsunami.

Storm Events records are more complete after 1996; before 1996 only Tornado (from 1950), Hail and Thunderstorm Wind (from 1955) exist. Zone-level records from zones that 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.

Supports FEMA checklist item B1-d: previous occurrences

Federal declarations for this county: 45 declarations covering 31 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

DeclaredIncident beganFEMA numberTypeTitleMapped hazardCounty Public Assistancefederal share obligated, nominal dollarsFlagsNotes
2026-01-242026-01-23EM-3638-LAEmergencySevere Winter StormWinter Weatherno Public Assistance recordednew since last plan; within last 5 years
2024-09-162024-09-09DR-4817-LAMajor disasterHurricane FrancineHurricane (primary); also designated: Tornado$3,276,114.79in the 12 months before plan approval; within last 5 years
2024-09-102024-09-10EM-3614-LAEmergencyTropical Storm FrancineHurricane (primary); also designated: Tornadono Public Assistance recordedin the 12 months before plan approval; within last 5 yearssame incident as DR-4817
2023-09-272023-09-20EM-3600-LAEmergencySeawater IntrusionOther, not an NRI hazard; not counted$15,609,971.12within last 5 years
2021-09-132021-09-12EM-3574-LAEmergencyTropical Storm NicholasHurricaneno Public Assistance recorded
2021-08-292021-08-26DR-4611-LAMajor disasterHurricane IdaHurricane$52,496,903.85
2021-08-272021-08-26EM-3568-LAEmergencyTropical Storm IdaHurricaneno Public Assistance recordedsame incident as DR-4611
2021-03-092021-02-11DR-4590-LAMajor disasterSevere Winter StormsIce Stormno Public Assistance recorded
2021-02-182021-02-11EM-3556-LAEmergencySevere Winter StormIce Stormno Public Assistance recordedsame incident as DR-4590
2021-01-122020-10-26DR-4577-LAMajor disasterHurricane ZetaHurricane$2,274,529.28
2020-10-272020-10-26EM-3549-LAEmergencyTropical Storm ZetaHurricaneno Public Assistance recordedsame incident as DR-4577
2020-10-162020-10-06DR-4570-LAMajor disasterHurricane DeltaHurricane$282,335.84
2020-10-072020-10-06EM-3547-LAEmergencyHurricane DeltaHurricaneno Public Assistance recordedsame incident as DR-4570
2020-09-142020-09-13EM-3543-LAEmergencyHurricane SallyHurricane$613,586.10
2020-08-282020-08-22DR-4559-LAMajor disasterHurricane LauraHurricane$649,832.14
2020-08-232020-08-22EM-3538-LAEmergencyTropical Storms Laura and MarcoHurricaneno Public Assistance recordedsame incident as DR-4559
2020-06-072020-06-05EM-3527-LAEmergencyTropical Storm CristobalHurricaneno Public Assistance recorded
2020-03-242020-01-20DR-4484-LAMajor disasterCOVID-19 PandemicNon-natural, not counted$2,684,309.79
2020-03-132020-01-20EM-3459-LAEmergencyCOVID-19Non-natural, not countedno Public Assistance recordedsame incident as DR-4484
2019-08-272019-07-10DR-4458-LAMajor disasterHurricane BarryHurricane$1,480,529.43
2019-07-112019-07-10EM-3416-LAEmergencyTropical Storm BarryHurricaneno Public Assistance recordedsame incident as DR-4458
2017-10-162017-08-28DR-4345-LAMajor disasterTropical Storm HarveyHurricane$507,462.98
2017-10-062017-10-05EM-3392-LAEmergencyTropical Storm NateHurricane$240,843.88
2016-02-052015-12-28EM-3376-LAEmergencyFloodingInland Flooding$98,136.71
2012-08-292012-08-26DR-4080-LAMajor disasterHurricane IsaacHurricane$46,457,816.06
2012-08-272012-08-26EM-3347-LAEmergencyTropical Storm IsaacHurricaneno Public Assistance recordedsame incident as DR-4080
2011-10-282011-09-01DR-4041-LAMajor disasterTropical Storm LeeHurricane$898,274.42
2008-09-132008-09-11DR-1792-LAMajor disasterHurricane IkeHurricane (primary); also designated: Inland Flooding$22,889,796.66
2008-09-022008-09-01DR-1786-LAMajor disasterHurricane GustavHurricane (primary); also designated: Inland Flooding$8,822,546.38
2008-08-292008-08-27EM-3289-LAEmergencyHurricane GustavHurricaneno Public Assistance recordedsame incident as DR-1786
2005-09-242005-09-23DR-1607-LAMajor disasterHurricane RitaHurricane$11,525
2005-09-212005-09-20EM-3260-LAEmergencyHurricane RitaHurricaneno Public Assistance recordedsame incident as DR-1607
2005-08-292005-08-29DR-1603-LAMajor disasterHurricane KatrinaHurricane$801,338,070.56
2005-08-272005-08-26EM-3212-LAEmergencyHurricane KatrinaHurricaneno Public Assistance recordedsame incident as DR-1603
2005-08-232005-07-05DR-1601-LAMajor disasterTropical Storm CindyHurricane$44,269.49
2004-09-152004-09-13DR-1548-LAMajor disasterHurricane IvanHurricane$936,881.47
2002-10-032002-10-01DR-1437-LAMajor disasterHurricane LiliHurricane$438,261.56
2002-09-272002-09-21DR-1435-LAMajor disasterTropical Storm IsidoreHurricane$380,166.30
1998-09-231998-09-09DR-1246-LAMajor disasterHurricane Georges/Ts FrancesHurricaneno Public Assistance recorded
1992-08-261992-08-25DR-956-LAMajor disasterHurricane AndrewHurricaneno Public Assistance recorded
1985-11-011985-10-26DR-752-LAMajor disasterHurricane JuanHurricanePA not declared for this county
1974-09-231974-09-23DR-448-LAMajor disasterHurricane CarmenHurricaneno Public Assistance recorded
1973-04-271973-04-27DR-374-LAMajor disasterSevere Storms & FloodingInland Floodingno Public Assistance recorded
1969-08-191969-08-19DR-272-LAMajor disasterHurricane CamilleHurricane (primary); also designated: Inland Floodingno Public Assistance recorded
1965-09-101965-09-10DR-208-LAMajor disasterHurricane BetsyHurricane (primary); also designated: Inland Floodingno Public Assistance recorded

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

DeclaredIncident beganFEMA numberTypeTitleMapped hazard
1964-10-031964-10-03DR-178-LAMajor disasterHurricane HildaHurricane (primary); also designated: Inland Flooding
1962-11-051962-11-05DR-139-LAMajor disasterChlorine Barge AccidentNon-natural, not counted
1958-05-201958-05-20DR-84-LAMajor disasterFloodsInland Flooding
1957-05-161957-05-16DR-73-LAMajor disasterFloods & HurricaneHurricane (primary); also designated: Inland Flooding
1956-10-041956-10-04DR-64-LAMajor disasterHurricaneHurricane (primary); also designated: Inland Flooding
1953-05-291953-05-29DR-3-LAMajor disasterFloodInland 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.

Previous occurrences by hazard, with explicit no-event rows

Sources: 2, 6, 7

HazardStorm Events records, all years on file(years in the Period column)Since plan approvalrecordsIn the 12 months before plan approvalrecordsLast 5 yearsrecordsDeclared incidents, all yearsseparate disastersDeclared since approvalseparate disastersPeriodStatement
Coastal Flooding28012001996 to 2026-06-30
Cold Wave4011001996 to 2026-06-30
Drought11209001996 to 2026-06-30
Earthquake000000Storm Events does not record earthquakes; the USGS earthquake catalog is the source.
Hail270010001955 to 2026-06-30
Heat Wave252024001996 to 2026-06-30
Hurricane320112701996 to 2026-06-30Includes 1 Tropical Depression record.
Ice Storm0000101996 to 2026-06-30No Storm Events records of this type; 1 federal declared incident (see declarations table)
Inland Flooding8000601996 to 2026-06-30
Landslide0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Lightning2000001996 to 2026-06-30
Strong Wind86125001955 to 2026-06-30Includes 2 High Wind records.
Tornado35023101950 to 2026-06-30
Tsunami0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Wildfire0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Winter Weather4012111996 to 2026-06-30

Notable Storm Events records

Sources: 1, 6, 7

DateEvent typeMagnitude or extentDamagenominal dollarsDeaths, injuriesdirect onlyLocationFlagsWhy listed
2023-08-04Excessive Heat$0 property; $0 crops (zone total, 2023 dollars)0, 0NWS zone LAZ090 (CENTRAL PLAQUEMINES PARISH), zone-levelwithin last 5 yearsB1-c worst recorded: Excessive Heat, Heat
2023-08-01Drought$0 property; $0 crops (zone total, 2023 dollars)0, 0NWS zone LAZ090 (CENTRAL PLAQUEMINES PARISH), zone-levelwithin last 5 yearsB1-c worst recorded: Drought
2022-05-15Hail2 in$0 property; $0 crops (2022 dollars)0, 0PORT NICKELwithin last 5 yearsB1-c worst recorded: Hail
2021-08-29Hurricane (NOAA event type 'Hurricane (Typhoon)')category 3$100,000,000 property; $0 crops (zone total, 2021 dollars)0, 0NWS zone LAZ063 (UPPER PLAQUEMINES), zone-levelB1-c worst recorded: Hurricane, Tropical Storm, Tropical Depression
2020-08-20Lightning$20,000 property; $0 crops (2020 dollars)0, 0SONE CHASSEB1-c worst recorded: Lightning
2012-08-28Storm Surge/Tide$49,800,000 property; $0 crops (zone total, 2012 dollars)2, 0NWS zone LAZ069 (LOWER PLAQUEMINES), zone-leveldeaths or injuries recorded
2010-08-01Excessive Heat$0 property; $0 crops (zone total, 2010 dollars)1, 0NWS zone LAZ069 (LOWER PLAQUEMINES), zone-leveldeaths or injuries recorded
2010-01-02Cold/Wind Chill$0 property; $50,000 crops (zone total, 2010 dollars)0, 0NWS zone LAZ063 (UPPER PLAQUEMINES), zone-levelB1-c worst recorded: Cold/Wind Chill, Extreme Cold/Wind Chill
2005-08-29Storm Surge/Tide$3,030,000,000 property; crops not reported (zone total, 2005 dollars)0, 0NWS zone LAZ069 (LOWER PLAQUEMINES), zone-levelB1-c worst recorded: Coastal Flood, Storm Surge/Tide
2005-08-28Hurricane (NOAA event type 'Hurricane (Typhoon)')$1,520,000,000 property; crops not reported (zone total, 2005 dollars)2, 0NWS zone LAZ069 (LOWER PLAQUEMINES), zone-leveldeaths or injuries recorded
2003-06-30Flash Flood$130,000 property; crops not reported (2003 dollars)0, 0COUNTYWIDEB1-c worst recorded: Flash Flood, Flood, Lakeshore Flood
1957-11-13TornadoF3, 3.6 mi path length (whole path, pre-1996), 200 yd wide$250 property; crops not recorded (1957 dollars)0, 0location not recordedB1-c worst recorded: Tornado

The full list is in the Excel file, sheet "B1-d Storm Events history" (262 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

HazardFEMA annualized frequency (modeled)unit per rowUnitIn plain termsDescriptorDescriptor basisNRI events or days in its record period (hail, wind and tornado are area-weighted, so can be fractional)NRI periodLocationNote
Coastal Flooding4.02events per year at a location (modeled)about 4 per year at a given location in the countyHighly likelyFEMA annualized frequency (modeled)not shownmodeledsee B1-fDescriptor from NRI: the rate at a location is 1 or more a year, so the county rate is at least that.
Cold Wave0.645event-days per yearabout 0.645 days per yearLikelyStorm Events event-days in 3 of 30 years, 1996 to 2025 (10%)10.42005-11-12 to 2024-11-12 (19 years)countywide
Drought27.6event-days per yearabout 27.6 days per yearLikelyStorm Events event-days in 3 of 30 years, 1996 to 2025 (10%)7562000 to 2025 (25.25 years; D3 and D4 only)countywide
Earthquake0.000777annual probability at a locationchance a given location in the county has at least minor-damage shaking in a year: 0.0777%not shownmodeledsee B1-fNo descriptor (Storm Events does not record earthquakes).
Hail0.45events per yearabout 1 in 2 yearsLikelyFEMA annualized frequency (modeled)23.5 (modeled)1986 to 2023 (38 years)countywide
Heat Wave11.1event-days per yearabout 11.1 days per yearLikelyStorm Events event-days in 3 of 30 years, 1996 to 2025 (10%)1442005-11-12 to 2024-11-12 (19 years)countywide
Hurricane0.266events per yearabout 1 in 4 yearsLikelyFEMA annualized frequency (modeled)1341851 to 2024 (Atlantic)see B1-fNRI counts hurricane and tropical storm tracks passing within storm-force wind range; federal declarations are in B1-d.
Ice Storm0.0149event-days per yearabout 0.0149 days per yearStorm Events event-days in 0 of 30 years, 1996 to 2025 (0%)01946-12-31 to 2014-02-12 (67 years)countywideNo Storm Events ice storm record, 1996 to 2025
Inland Flooding0.286event-days per yearabout 0.286 days per yearLikelyStorm Events event-days in 7 of 30 years, 1996 to 2025 (23.3%)81996 to 2023 (28 years)see B1-f
Landslide0.085events per year (modeled)about 1 in 12 yearsPossibleFEMA annualized frequency (modeled)not shownmodeledsee B1-f
Lightning81.2days per year with a strikeabout 81.2 days per yearHighly likelyFEMA annualized frequency (modeled)not shown1995 to 2023 (29 years; CONUS)countywide
Strong Wind0.506events per yearabout 0.51 per yearLikelyFEMA annualized frequency (modeled)111986 to 2023 (38 years)countywide
Tornado0.682events per yearabout 0.68 per yearLikelyFEMA annualized frequency (modeled)not shown1950 to 2023 (EF2+); 1986 to 2023 (EF0-1)see B1-f
Tsunamiannual 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 shownmodeledsee B1-fNo descriptor: no Storm Events record 1996 to 2025
Wildfire0.000152annual probability at a locationchance a given location in the county burns in a year: 0.0152%Storm Events records in 0 of 30 years, 1996 to 2025 (0%)not shownmodeledsee B1-fNo descriptor: no Storm Events record 1996 to 2025
Winter Weather0.267event-days per yearabout 0.267 days per yearLikelyStorm Events event-days in 4 of 30 years, 1996 to 2025 (13.3%)3.772005-11-12 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

UnitDescriptorDefinition
events per yearHighly likely1 or more per year
events per yearLikelyabout once in 1 to 10 years
events per yearPossibleabout once in 10 to 100 years
events per yearUnlikelyless than once in 100 years
annual probabilityLikely10% to under 100% chance in a given year
annual probabilityPossible1% to under 10% chance in a given year
annual probabilityUnlikelyunder 1% chance in a given year
event-days (share of years)Highly likelyevent-days recorded in 90% or more of years
event-days (share of years)Likelyevent-days recorded in 10% to under 90% of years
event-days (share of years)Possibleevent-days recorded in some years but under 10% of years
lightning strike-daysHighly likelycloud-to-ground strikes on 1 or more days per year

Intensity bands: historical frequency (Storm Events)

Source: 6

HazardBandYearsEventscounty-coded recordsYears in periodEvents per yearevents / years
Hail1.00-1.99 in1996 to 202515300.5
Hail2.00 in+1996 to 20252300.0667
Thunderstorm Wind (counted as NRI Strong Wind)50-64 kt1996 to 202524300.8
Thunderstorm Wind (counted as NRI Strong Wind)65 kt+1996 to 20254300.133
Thunderstorm Wind (counted as NRI Strong Wind)unmeasured or below 50 kt1996 to 202516300.533
TornadoEF0-11996 to 202517300.567
TornadoEF2-31996 to 20250300
TornadoEF4-51996 to 20250300
Tornadounrated (EFU)1996 to 20252300.0667

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

HazardTractsrated of allNRI risk score, 0 to 100Tracts by rating
MinMedianMax
Coastal Flooding9 of 987.790.999.7Very High 2, Relatively High 1, Relatively Moderate 4, Relatively Low 2
Cold Wave9 of 928.349.281.7Relatively High 2, Relatively Moderate 3, Relatively Low 4
Drought4 of 985.590.999.4Relatively High 1, Relatively Moderate 1, Relatively Low 2, No Rating 5
Earthquake9 of 910.617.247.1Relatively Low 1, Very Low 8
Hail9 of 922.052.176.8Relatively Moderate 2, Relatively Low 3, Very Low 4
Heat Wave9 of 917.951.188.1Relatively High 2, Relatively Moderate 2, Relatively Low 5
Hurricane9 of 993.696.999.8Very High 4, Relatively High 5
Ice Storm9 of 93.25.524.5Very Low 9
Inland Flooding9 of 90.72.278.4Relatively Moderate 3, Very Low 6
Landslide9 of 921.834.372.8Very Low 9
Lightning9 of 937.267.192.3Relatively High 4, Relatively Moderate 3, Relatively Low 2
Strong Wind9 of 92.715.632.2Relatively Low 4, Very Low 5
Tornado9 of 919.551.878.2Relatively High 1, Relatively Moderate 3, Relatively Low 3, Very Low 2
Tsunami0 of 9Insufficient Data 9
Wildfire9 of 947.754.878.2Relatively Low 2, Very Low 7
Winter Weather9 of 916.727.260.7Relatively Moderate 3, Relatively Low 3, Very Low 3

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

JurisdictionTypePlan statusRepetitive lossFMA RL and SRL (44 CFR 77.2); repeat-flood, any definitionPublic Assistance to this jurisdictionFEMA records matched by applicant name; federal share obligated, nominal dollarsEvent records naming this placeall years; since its planNotes
Plaquemines ParishCountyApproved, expires 2030-06-24FMA RL 225, SRL 175; any 475$537,344,515.490 total; 0 since its planIncludes $15,697,358.37 for declarations not counted as hazard incidents (DR-4484-LA, EM-3600-LA).

Repetitive-loss counts are for whole NFIP communities, which can extend beyond this county (see the note in B2-c).

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

HazardBuilding exposuremodeled dollarsAgriculture exposuremodeled dollarsPopulation exposedpeopleEAL buildingsmodeled dollars per yearEAL agriculturemodeled dollars per yearCost of expected deaths and injuriesFEMA's dollar value per year, not property damageEAL as % of exposurebuildings; agriculture where notedStorm Events damage since 2025-06-25county-coded records, property plus crops, nominal dollarsZone-level damage since planproperty plus crops, reported for the zonePublic Assistance since plannominal dollars; see noteNote
Coastal Flooding$5,462,853,466n/a23,430$2,668,920n/a$130,8910.0489%
Cold Wave$5,467,152,903$13,891,30223,448$3,108$5,202$700,213under 0.0001%
Droughtn/a$3,269,486n/an/a$960,612n/a29.4% (agriculture)$0NRI has no building exposure for this hazard; agriculture shown
Earthquake$9,520,051,480n/a23,515$49,164n/a$14,5170.000516%
Hail$5,467,152,903$13,891,30223,448$86,856$1$9,1500.00159%
Heat Wave$5,467,152,903$13,891,30223,448$231$51$588,762under 0.0001%$0
Hurricane$5,466,657,002$13,891,30223,445$18,165,770$158,452$781,0380.332%
Ice Storm$5,467,152,903n/a23,448$4,927n/a$1,600under 0.0001%
Inland Flooding$5,365,642,942$13,530,08312,891$2,697,414$18$40,758n/a (see note)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$19,316,445n/a83$59n/a$30.000303%
Lightning$5,467,152,903n/a23,448$9,318n/a$206,4500.00017%
Strong Wind$5,467,152,903$13,891,30223,448$9,812$38$18,5030.000179%$0
Tornado$5,467,152,903$13,891,30223,448$319,222$198$454,0150.00584%
Tsunamin/an/an/an/an/an/aNRI publishes no building exposure for this county
Wildfire$574,763,615$6,703,2013,236$6,239$7$6790.00109%
Winter Weather$5,467,152,903$13,891,30223,448$3,827$7$8,702under 0.0001%no Public Assistance recorded (1 declaration)

Totals since 2025-06-25 (Storm Events through 2026-06-30): 1 county-coded records, 1 with a damage value recorded (including $0), $0; 4 zone-level records, 4 with a damage value recorded (including $0), $0 reported for the zone; Public Assistance: none recorded on the 1 counted declaration.

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

MeasureValue
Population23,448
Building value (total, not at risk)$5,467,152,903
Agriculture value (total, not at risk)$13,891,302
NRI risk rating (all hazards)Relatively Low
Expected annual loss, buildings and agriculture, all hazards$25,149,452
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)$2,955,280
Social vulnerability ratingRelatively Moderate
Community resilience ratingVery High
NRI versionDecember 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

DefinitionPropertiesSevere repetitive lossProperties
Repetitive loss, FMA definition (44 CFR 77.2)225Severe repetitive loss, FMA definition (44 CFR 77.2)175
Repetitive loss, NFIP insurance definition426Severe repetitive loss, NFIP insurance definition128

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

ScopeRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
County total22517542612847554151
of which: Plaquemines Parish (unincorporated area)22517542612847554151
Statewide, no county in FEMA's file0040400

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

JurisdictionNFIP community IDRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
Plaquemines Parish22013922517542612847554151

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 groupRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
single-family residential21115736211540748141
2 to 4 unit residential3161602
other residential0060600
non-residential111752125668
not reported0000000

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 37 properties are FMA repetitive loss but not NFIP repetitive loss, and 238 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):

  1. FEMA, OpenFEMA HazardMitigationPlanStatuses v1, version 2026-09-29T134039Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/HazardMitigationPlanStatuses (API)
  2. FEMA, OpenFEMA DisasterDeclarationsSummaries v2, version 2026-09-29T162832Z, pulled 2026-09-30, https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries (API)
  3. FEMA, OpenFEMA PublicAssistanceFundedProjectsSummaries v1, version 2026-09-29T150754Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/PublicAssistanceFundedProjectsSummaries (API)
  4. FEMA, OpenFEMA NfipMultipleLossProperties v1, version 2026-08-04T164045Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/NfipMultipleLossProperties (API)
  5. 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)
  6. 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/
  7. 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
  8. 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 (the summary on page 1 says how it is organized); the plan and FEMA's review decide whether each 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). Plaquemines Parish, LA: risk-assessment baseline packet, release 2026-10 (data as of 2026-09-30; County FIPS 22075). Automated baseline. https://hazardplain.org/la/22075/ 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]