Hazard Plain Automated baseline

Southeastern Connecticut Planning Region, CT

Risk-assessment baseline packet

Planning region FIPS:
09180
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: No county-level plan row in FEMA data.

Highest expected annual loss (FEMA National Risk Index, modeled total; see B1-a): Inland Flooding ($52,098,600 a year), Hurricane ($22,302,862) and Earthquake ($1,991,618).

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

No county-level plan row in FEMA data

What changed since your last plan

Not available. Connecticut planning regions have no county-level plan in FEMA data; see each town's plan dates in the region.

Sources: 1, 2, 4, 6 (numbered list at the end)

Plan status for every jurisdiction listed in this planning region: 26 rows, in the section "Plan clock: Plan status for every jurisdiction listed in this planning region" 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 planning region

Source: 1

JurisdictionTypeStatusPlanApprovedExpiresDays to expirynegative = days since expiryNotes
Groton cityCityApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Jewett City boroughBoroughApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727this jurisdiction approved 2024-01-03
New London cityCityApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Norwich cityCityApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Stonington boroughBoroughApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Bozrah townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Colchester townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
East Lyme townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727this jurisdiction approved 2024-01-03
Franklin townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Griswold townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727this jurisdiction approved 2024-01-03
Groton townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Lebanon townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727this jurisdiction approved 2024-08-21
Ledyard townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Lisbon townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Montville townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
North Stonington townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Preston townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Salem townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Sprague townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Stonington townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Waterford townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727this jurisdiction approved 2024-01-03
Windham townTownApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727
Eastern Connecticut StateCollege/UniversityExpired on 2022-06-01Connecticut State Colleges and Universities (FEMA plan 102570)2017-06-022022-06-01-1,582
Quinebaug Valley CommunityCollege/UniversityExpired on 2022-06-01Connecticut State Colleges and Universities (FEMA plan 102570)2017-06-022022-06-01-1,582
Southeastern Connecticut Council of GovernmentsOtherApproved, expires 2028-09-26Southeastern Connecticut Council of Governments Multi-Jurisdictional Hazard Mitigation Plan Update (FEMA plan 109036)2023-09-272028-09-26727this jurisdiction approved 2025-06-11
Three Rivers CommunityCollege/UniversityExpired on 2022-06-01Connecticut State Colleges and Universities (FEMA plan 102570)2017-06-022022-06-01-1,582

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
1Inland FloodingRelatively ModerateRelatively Moderate$52,052,335$60$46,204$52,098,600160
2HurricaneRelatively HighRelatively High$20,338,070$1,324,276$640,516$22,302,8627
3EarthquakeRelatively LowRelatively Low$1,690,321n/a$301,297$1,991,618Storm Events does not record earthquakes.
4TornadoRelatively LowRelatively Low$1,197,966$2,943$323,044$1,523,95310
5Coastal FloodingRelatively ModerateRelatively Moderate$1,304,675n/a$13,033$1,317,7079
6Heat WaveRelatively LowRelatively Low$1$18,036$1,055,278$1,073,31611
7Cold WaveRelatively LowRelatively Low$543$12,800$800,694$814,0374
8Strong WindRelatively ModerateRelatively Moderate$181,091$240$569,809$751,140395Includes 67 High Wind and 53 Strong Wind records (NOAA non-thunderstorm wind types, outside NRI's Strong Wind definition).
9LightningRelatively ModerateRelatively Moderate$33,568n/a$642,963$676,53125
10Ice StormRelatively ModerateRelatively Moderate$273,533n/a$121,371$394,9043
11HailRelatively LowRelatively Low$9,662$5,414$226,588$241,66493
12Winter WeatherRelatively ModerateRelatively Moderate$29,116$68$170,688$199,871215
13DroughtRelatively LowRelatively Lown/a$36,156n/a$36,15610
14WildfireVery LowVery Low$22,711$17$4,961$27,6890No recorded events in Storm Events since 1996 (data through 2026-06-30).
15LandslideRelatively LowRelatively Low$10,100n/a$1,996$12,0960No 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 6967.01 (Relatively Low, 75.7); tract 8003 (Relatively Low, 75.2); tract 8703 (Relatively Low, 70.8)
Hurricanetract 8701 (Relatively High, 93.5); tract 8003 (Relatively High, 91.6); tract 7151 (Relatively High, 91.2)
Landslidetract 7011 (Relatively Low, 92.6); tract 7131 (Relatively Low, 92.4); tract 7001 (Relatively Low, 91.0)
Tornadotract 8003 (Relatively Low, 52.2); tract 8701 (Relatively Low, 49.1); tract 6967.01 (Relatively Low, 48.5)
Tsunamino tract has a National Risk Index rating for this hazard
Wildfiretract 7141.04 (Relatively Low, 72.3); tract 7141.03 (Relatively Low, 70.8); tract 7151 (Relatively Low, 69.6)

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 6967.01 is Census Tract 6967.01). 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)9 records, 1996 to 2024 (9 zone-level)No damage reported in 9 records.Countywide (zone-level records).Flood depth: see the FEMA Flood Insurance Rate Map.
Cold/Wind Chill, Extreme Cold/Wind Chillwind chill4 records, 2000 to 2023 (4 zone-level)1 day to 2 days (median 1.5 days); 4 with a recorded value2 consecutive days, 2004-01-15 to 2004-01-16, zone-levelCountywide (zone-level records).
Frost/Freeze (outside NRI's Cold Wave definition)crop damage0
DroughtU.S. Drought Monitor scale (D0 to D4)10 records, 2002 to 2017 (10 zone-level)8 days to 124 days (median 44.5 days); 4 with a recorded value124 days (about 4.1 months), 2016-10-01 to 2017-02-01, a run of 5 consecutive Storm Events drought records, zone-levelCountywide (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)111 records, 1963 to 20250.75 in to 2.75 in (median 1 in); 111 with a recorded value2.75 in hail, 1969-05-29Hail, 2025-07-03, $5,000 property; $0 crops (2025 dollars)Event records naming jurisdictions in the plan: Norwich city (8 records), Colchester town (5 records), Windham town (4 records), Franklin town (3 records), Jewett City borough (3 records), New London city (2 records), Preston town (2 records), North Stonington town (1 record), Salem town (1 record), Waterford town (1 record).
Excessive Heat, Heatheat index (in event narratives)11 records, 1999 to 2019 (11 zone-level)1 day to 3 days (median 2 days); 7 with a recorded value3 consecutive days, 2002-07-02 to 2002-07-04, zone-levelCountywide (zone-level records).
Hurricane, Tropical Storm, Tropical DepressionSaffir-Simpson7 records, 2008 to 2021 (7 zone-level)Strongest recorded: Tropical Storm record, 2011-08-28, $20,000,000 property; $0 crops (2011 dollars); NWS zone CTZ004Countywide (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)3 records, 1998 to 2011 (3 zone-level)No damage reported in 3 records.Countywide (zone-level records).
Flash Flood, Flood, Lakeshore Flooddamage and flood days (flood depth: FIRM)160 records, 1996 to 2024 (8 zone-level)Flood, 2010-03-30, $4,000,000 property; $0 crops (2010 dollars)Event records naming jurisdictions in the plan: New London city (17 records), Norwich city (9 records), Windham town (6 records), Lebanon town (5 records), Jewett City borough (3 records), Colchester town (2 records), Groton city (2 records), Groton town (2 records), North Stonington town (2 records), Stonington borough (2 records); and 5 more jurisdictions (see the Excel file). Zone-level records (8) 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 Flownone (count and damage only)0
Lightningannualized frequency (the measure FEMA's Local Mitigation Planning Handbook names)25 records, 1997 to 2025Lightning, 1997-06-19, damage not reported, 1 direct deathLightning, 2016-08-13, $15,000 property; $0 crops (2016 dollars)Event records naming jurisdictions in the plan: Norwich city (5 records), Stonington borough (3 records), Stonington town (3 records), Griswold town (1 record), North Stonington town (1 record), Preston town (1 record).Storm Events lists lightning with damage or casualties.
High Wind and Strong Wind (outside NRI's Strong Wind definition)wind speed (kt and mph)120 records, 1996 to 2026 (120 zone-level)28 kt (32 mph) to 65 kt (75 mph) (median 50 kt (58 mph)); 95 with a recorded value65 kt (75 mph) measured gust, High Wind, 2012-10-29; NWS zone CTZ012High Wind, 2012-10-29, $1,000,000 property; $0 crops (zone total, 2012 dollars)Countywide (zone-level records).
Thunderstorm Windwind speed (kt and mph)320 records, 1956 to 202640 kt (46 mph) to 74 kt (85 mph) (median 50 kt (58 mph)); 279 with a recorded value74 kt (85 mph) estimated gust, Thunderstorm Wind, 2008-07-02Event records naming jurisdictions in the plan: Colchester town (12 records), Lebanon town (11 records), Norwich city (11 records), Windham town (11 records), Franklin town (10 records), Salem town (6 records), Jewett City borough (5 records), North Stonington town (5 records), Groton city (2 records), Groton town (2 records); and 6 more jurisdictions (see the Excel file).
TornadoEnhanced Fujita (Fujita before Feb 2007)13 records, 1985 to 2023F/EF0 to F/EF1 (median F/EF1); 13 with a recorded valueF1 tornado, 1985-06-24, 10 mi path length (whole path, pre-1996), 100 yd wide, $2,500,000 property; crops not recorded (1985 dollars)Event records naming jurisdictions in the plan: Montville 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).
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)215 records, 1996 to 2026 (215 zone-level)Heavy Snow, 1996-12-07, $1,000,000 property; crops not reported (1996 dollars); NWS zone CTZ004Countywide (zone-level records).

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".

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: 58 declarations covering 23 separate hazard incidents counted in this packet (declarations for the same incident count once; non-natural and evacuation-only declarations are not counted).

Connecticut planning regions have no county-level plan in FEMA data; see each town's plan dates in the region.

Federal disaster declarations for this county

Sources: 1, 2, 3

DeclaredIncident beganFEMA numberTypeTitleMapped hazardCounty Public Assistancefederal share obligated, nominal dollarsFlagsNotes
2024-01-132024-01-10EM-3604-CTEmergencySevere Storms, Flooding, and a Potential Dam BreachInland Floodingwithin last 5 yearsformer New London County total, not this region: no Public Assistance recorded
2021-10-302021-09-01DR-4629-CTMajor disasterRemnants of Hurricane IdaHurricanewithin last 5 yearsformer New London County total, not this region: no Public Assistance recorded
2021-08-222021-08-21EM-3564-CTEmergencyHurricane HenriHurricaneformer Windham County total, not this region: no Public Assistance recorded
2021-08-222021-08-21EM-3564-CTEmergencyHurricane HenriHurricaneformer New London County total, not this region: $5,339.02
2021-01-122020-08-04DR-4580-CTMajor disasterTropical Storm IsaiasHurricaneformer Windham County total, not this region: $235,171.29
2021-01-122020-08-04DR-4580-CTMajor disasterTropical Storm IsaiasHurricaneformer New London County total, not this region: $1,074,018.28
2020-08-062020-08-04EM-3535-CTEmergencyTropical Storm IsaiasHurricanesame incident as DR-4580; former Windham County total, not this region: no Public Assistance recorded
2020-08-062020-08-04EM-3535-CTEmergencyTropical Storm IsaiasHurricanesame incident as DR-4580; former New London County total, not this region: no Public Assistance recorded
2020-03-282020-01-20DR-4500-CTMajor disasterCOVID-19 PandemicNon-natural, not countedformer Windham County total, not this region: $2,030,946.15
2020-03-282020-01-20DR-4500-CTMajor disasterCOVID-19 PandemicNon-natural, not countedformer New London County total, not this region: $27,151,096.56
2020-03-132020-01-20EM-3439-CTEmergencyCOVID-19Non-natural, not countedsame incident as DR-4500; former Windham County total, not this region: no Public Assistance recorded
2020-03-132020-01-20EM-3439-CTEmergencyCOVID-19Non-natural, not countedsame incident as DR-4500; former New London County total, not this region: no Public Assistance recorded
2018-12-052018-09-25DR-4410-CTMajor disasterSevere Storms and FloodingInland Floodingformer New London County total, not this region: $491,639.85
2015-04-082015-01-26DR-4213-CTMajor disasterSevere Winter Storm and SnowstormWinter Weatherformer Windham County total, not this region: $667,486.34
2015-04-082015-01-26DR-4213-CTMajor disasterSevere Winter Storm and SnowstormWinter Weatherformer New London County total, not this region: $1,856,741.77
2013-03-212013-02-08DR-4106-CTMajor disasterSevere Winter Storm and SnowstormWinter Weatherformer Windham County total, not this region: $458,100.76
2013-03-212013-02-08DR-4106-CTMajor disasterSevere Winter Storm and SnowstormWinter Weatherformer New London County total, not this region: $1,798,115.14
2013-02-102013-02-08EM-3361-CTEmergencySevere Winter StormWinter Weathersame incident as DR-4106; former Windham County total, not this region: no Public Assistance recorded
2013-02-102013-02-08EM-3361-CTEmergencySevere Winter StormWinter Weathersame incident as DR-4106; former New London County total, not this region: no Public Assistance recorded
2012-10-302012-10-27DR-4087-CTMajor disasterHurricane SandyHurricaneformer Windham County total, not this region: $154,388.96
2012-10-302012-10-27DR-4087-CTMajor disasterHurricane SandyHurricaneformer New London County total, not this region: $5,508,478.74
2012-10-282012-10-27EM-3353-CTEmergencyHurricane SandyHurricanesame incident as DR-4087; former Windham County total, not this region: no Public Assistance recorded
2012-10-282012-10-27EM-3353-CTEmergencyHurricane SandyHurricanesame incident as DR-4087; former New London County total, not this region: no Public Assistance recorded
2011-11-172011-10-29DR-4046-CTMajor disasterSevere StormHazard not mapped (severe storm title names no single hazard); not countedformer Windham County total, not this region: $122,595.37
2011-10-312011-10-29EM-3342-CTEmergencySevere StormHazard not mapped (severe storm title names no single hazard); not countedsame incident as DR-4046; former Windham County total, not this region: no Public Assistance recorded
2011-10-312011-10-29EM-3342-CTEmergencySevere StormHazard not mapped (severe storm title names no single hazard); not countedsame incident as DR-4046; former New London County total, not this region: $26,307.80
2011-09-022011-08-27DR-4023-CTMajor disasterTropical Storm IreneHurricaneformer Windham County total, not this region: $599,278.65
2011-09-022011-08-27DR-4023-CTMajor disasterTropical Storm IreneHurricaneformer New London County total, not this region: $5,387,536.15
2011-08-272011-08-26EM-3331-CTEmergencyHurricane IreneHurricanesame incident as DR-4023; former Windham County total, not this region: no Public Assistance recorded
2011-08-272011-08-26EM-3331-CTEmergencyHurricane IreneHurricanesame incident as DR-4023; former New London County total, not this region: no Public Assistance recorded
2011-03-032011-01-11DR-1958-CTMajor disasterSnowstormWinter Weatherformer New London County total, not this region: $1,002,297.46
2010-04-232010-03-12DR-1904-CTMajor disasterSevere Storms and FloodingInland Floodingformer Windham County total, not this region: no Public Assistance recorded
2010-04-232010-03-12DR-1904-CTMajor disasterSevere Storms and FloodingInland Floodingformer New London County total, not this region: $5,063,960.60
2007-05-112007-04-15DR-1700-CTMajor disasterSevere Storms and FloodingInland Floodingformer Windham County total, not this region: no Public Assistance recorded
2007-05-112007-04-15DR-1700-CTMajor disasterSevere Storms and FloodingInland Floodingformer New London County total, not this region: no Public Assistance recorded
2006-05-022006-02-11EM-3266-CTEmergencySnowWinter Weatherformer Windham County total, not this region: $259,952.34
2005-12-162005-10-14DR-1619-CTMajor disasterSevere Storms and FloodingInland Floodingformer Windham County total, not this region: $412,946.32
2005-12-162005-10-14DR-1619-CTMajor disasterSevere Storms and FloodingInland Floodingformer New London County total, not this region: $435,040.46
2005-09-132005-08-29EM-3246-CTEmergencyHurricane Katrina EvacuationHurricane: evacuation support, not a local hazard event; not countedformer Windham County total, not this region: no Public Assistance recorded
2005-09-132005-08-29EM-3246-CTEmergencyHurricane Katrina EvacuationHurricane: evacuation support, not a local hazard event; not countedformer New London County total, not this region: no Public Assistance recorded
2005-02-172005-01-22EM-3200-CTEmergencyRecord SnowWinter Weatherformer Windham County total, not this region: $286,231.71
2005-02-172005-01-22EM-3200-CTEmergencyRecord SnowWinter Weatherformer New London County total, not this region: $784,972.33
2004-01-152003-12-05EM-3192-CTEmergencySnowWinter Weatherformer Windham County total, not this region: $236,943.06
2004-01-152003-12-05EM-3192-CTEmergencySnowWinter Weatherformer New London County total, not this region: $600,136.75
2003-03-112003-02-17EM-3176-CTEmergencySnowWinter Weatherformer Windham County total, not this region: $172,632.90
2003-03-112003-02-17EM-3176-CTEmergencySnowWinter Weatherformer New London County total, not this region: $440,704.05
1996-01-241996-01-07DR-1092-CTMajor disasterBlizzard 0F 96Winter Weatherformer Windham County total, not this region: no Public Assistance recorded
1996-01-241996-01-07DR-1092-CTMajor disasterBlizzard 0F 96Winter Weatherformer New London County total, not this region: no Public Assistance recorded
1993-03-161993-03-13EM-3098-CTEmergencySevere Winds & Blizzard, Record SnowfallWinter Weatherformer Windham County total, not this region: no Public Assistance recorded
1993-03-161993-03-13EM-3098-CTEmergencySevere Winds & Blizzard, Record SnowfallWinter Weatherformer New London County total, not this region: no Public Assistance recorded
1991-08-301991-08-19DR-916-CTMajor disasterHurricane BobHurricaneformer Windham County total, not this region: no Public Assistance recorded
1991-08-301991-08-19DR-916-CTMajor disasterHurricane BobHurricaneformer New London County total, not this region: no Public Assistance recorded
1985-10-111985-09-27DR-747-CTMajor disasterHurricane GloriaHurricaneformer Windham County total, not this region: no Public Assistance recorded
1985-10-111985-09-27DR-747-CTMajor disasterHurricane GloriaHurricaneformer New London County total, not this region: no Public Assistance recorded
1982-06-141982-06-14DR-661-CTMajor disasterSevere Storms & FloodingInland Floodingformer Windham County total, not this region: no Public Assistance recorded
1982-06-141982-06-14DR-661-CTMajor disasterSevere Storms & FloodingInland Floodingformer New London County total, not this region: no Public Assistance recorded
1978-02-071978-02-07EM-3060-CTEmergencyBlizzard & SnowstormsWinter Weatherformer Windham County total, not this region: no Public Assistance recorded
1978-02-071978-02-07EM-3060-CTEmergencyBlizzard & SnowstormsWinter Weatherformer New London County total, not this region: no Public Assistance recorded

Old-county PA is never summed into a region total.

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
1955-08-201955-08-20DR-42-CTMajor disasterHurricane, Torrential Rain & FloodsHurricane (primary); also designated: Inland Flooding
1954-09-171954-09-17DR-25-CTMajor disasterHurricanesHurricane (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.

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 Flooding9201996 to 2026-06-30
Cold Wave4101996 to 2026-06-30
Drought10001996 to 2026-06-30
Earthquake000Storm Events does not record earthquakes; the USGS earthquake catalog is the source.
Hail1111101955 to 2026-06-30
Heat Wave11001996 to 2026-06-30
Hurricane7071996 to 2026-06-30
Ice Storm3001996 to 2026-06-30
Inland Flooding1601961996 to 2026-06-30
Landslide0001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Lightning25401996 to 2026-06-30
Strong Wind4408901955 to 2026-06-30Includes 67 High Wind and 53 Strong Wind records.
Tornado13401950 to 2026-06-30
Tsunami0001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Wildfire0001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Winter Weather21528101996 to 2026-06-30

Notable Storm Events records

Sources: 1, 6, 7

DateEvent typeMagnitude or extentDamagenominal dollarsDeaths, injuriesdirect onlyLocationWhy listed
2017-09-06Thunderstorm Wind56 kt (64 mph) estimated gust$15,000 property; crops not reported (2017 dollars)1, 1RIDGEWOOD (former New London County record)deaths or injuries recorded
2015-08-04Thunderstorm Wind52 kt (60 mph) estimated gust$10,000 property; crops not reported (2015 dollars)1, 0WEST MYSTIC (former New London County record)deaths or injuries recorded
2012-10-29High Wind65 kt (75 mph) measured gust$300,000 property; $0 crops (zone total, 2012 dollars)0, 0NWS zone CTZ012 (SOUTHERN NEW LONDON), zone-levelB1-c worst recorded: High Wind and Strong Wind
2011-08-28Tropical Storm$20,000,000 property; $0 crops (zone total, 2011 dollars)0, 0NWS zone CTZ004 (WINDHAM), zone-levelB1-c worst recorded: Hurricane, Tropical Storm, Tropical Depression
2010-03-30Flood$4,000,000 property; $0 crops (2010 dollars)0, 0CLARKS FALLS (former New London County record)B1-c worst recorded: Flash Flood, Flood, Lakeshore Flood
2008-07-02Thunderstorm Wind74 kt (85 mph) estimated gust$100,000 property; $0 crops (2008 dollars)0, 0NORTHWICHTOWN (former New London County record)B1-c worst recorded: Thunderstorm Wind
2005-10-15Flood$600,000 property; crops not reported (zone total, 2005 dollars)1, 0NWS zone CTZ004 (WINDHAM), zone-leveldeaths or injuries recorded
2004-01-15Cold/Wind Chilldamage not reported0, 0NWS zone CTZ008 (NORTHERN NEW LONDON), zone-levelB1-c worst recorded: Cold/Wind Chill, Extreme Cold/Wind Chill
2002-07-02Heatdamage not reported0, 0NWS zone CTZ008 (NORTHERN NEW LONDON), zone-levelB1-c worst recorded: Excessive Heat, Heat
1997-06-19Lightningdamage not reported1, 0GRISWOLD (former New London County record)B1-c worst recorded: Lightning
1985-06-24TornadoF1, 10 mi path length (whole path, pre-1996), 100 yd wide$2,500,000 property; crops not recorded (1985 dollars)0, 0location not recorded (former Windham County record)B1-c worst recorded: Tornado
1969-05-29Hail2.75 indamage not recorded (pre-1996 record)0, 0location not recorded (former New London County record)B1-c worst recorded: Hail

The full list is in the Excel file, sheet "B1-d Storm Events history" (1,008 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 Flooding3.72events per year at a location (modeled)about 3.7 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 Wave0.904event-days per yearabout 0.904 days per yearLikelyStorm Events event-days in 3 of 30 years, 1996 to 2025 (10%)15.52005-11-12 to 2024-11-12 (19 years)countywide
Drought1.09event-days per yearabout 1.09 days per yearLikelyStorm Events event-days in 4 of 30 years, 1996 to 2025 (13.3%)912000 to 2025 (25.25 years; D3 and D4 only)countywide
Earthquake0.00114annual probability at a locationchance a given location in the county has at least minor-damage shaking in a year: 0.114%not shownmodeledsee B1-fNo descriptor (Storm Events does not record earthquakes).
Hail1.75events per yearabout 1.75 per yearHighly likelyFEMA annualized frequency (modeled)70.1 (modeled)1986 to 2023 (38 years)countywide
Heat Wave4.46event-days per yearabout 4.46 days per yearLikelyStorm Events event-days in 7 of 30 years, 1996 to 2025 (23.3%)66.32005-11-12 to 2024-11-12 (19 years)countywide
Hurricane0.186events per yearabout 1 in 5 yearsLikelyFEMA annualized frequency (modeled)681851 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 Storm1.74event-days per yearabout 1.74 days per yearLikelyStorm Events event-days in 3 of 30 years, 1996 to 2025 (10%)1101946-12-31 to 2014-02-12 (67 years)countywide
Inland Flooding2.25event-days per yearabout 2.25 days per yearLikelyStorm Events event-days in 26 of 30 years, 1996 to 2025 (86.7%)631996 to 2023 (28 years)see B1-f
Landslide0.463events per year (modeled)about 1 in 2 yearsLikelyFEMA annualized frequency (modeled)not shownmodeledsee B1-f
Lightning23.2days per year with a strikeabout 23.2 days per yearHighly likelyFEMA annualized frequency (modeled)not shown1995 to 2023 (29 years; CONUS)countywide
Strong Wind1.63events per yearabout 1.63 per yearHighly likelyFEMA annualized frequency (modeled)601986 to 2023 (38 years)countywide
Tornado0.163events per yearabout 1 in 6 yearsLikelyFEMA 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
Wildfire0.0000667annual probability at a locationchance a given location in the county burns in a year: 0.00667%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 Weather13.3event-days per yearabout 13.3 days per yearHighly likelyStorm Events event-days in 29 of 30 years, 1996 to 2025 (96.7%)2292005-11-12 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 202549301.63
Hail2.00 in+1996 to 20250300
Thunderstorm Wind (counted as NRI Strong Wind)50-64 kt1996 to 2025263308.77
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 20256300.2
TornadoEF0-11996 to 202510300.333
TornadoEF2-31996 to 20250300
TornadoEF4-51996 to 20250300
Tornadounrated (EFU)1996 to 20250300

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 Flooding40 of 6769.884.097.8Relatively High 2, Relatively Moderate 13, Relatively Low 17, Very Low 8, No Rating 21, Not Applicable 6
Cold Wave67 of 6717.224.047.1Relatively Low 63, Very Low 4
Drought26 of 6767.973.586.4Relatively Low 7, Very Low 19, No Rating 41
Earthquake67 of 6718.344.375.7Relatively Low 37, Very Low 30
Hail67 of 6711.335.756.9Relatively Low 27, Very Low 40
Heat Wave67 of 673.118.955.4Relatively Low 39, Very Low 28
Hurricane67 of 6774.085.893.5Relatively High 8, Relatively Moderate 57, Relatively Low 2
Ice Storm67 of 676.747.285.3Relatively Moderate 6, Relatively Low 42, Very Low 19
Inland Flooding67 of 673.158.393.4Relatively High 12, Relatively Moderate 30, Relatively Low 18, Very Low 7
Landslide67 of 6726.773.592.6Relatively Low 22, Very Low 45
Lightning67 of 6711.242.871.3Relatively Moderate 20, Relatively Low 44, Very Low 3
Strong Wind67 of 6712.236.264.1Relatively Moderate 4, Relatively Low 60, Very Low 3
Tornado67 of 677.631.152.2Relatively Low 42, Very Low 25
Tsunami0 of 67Not Applicable 6, Insufficient Data 61
Wildfire66 of 6721.945.172.3Relatively Low 5, Very Low 61, No Rating 1
Winter Weather67 of 6724.051.075.1Relatively Moderate 40, Relatively Low 27

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
Groton cityCityApproved, expires 2028-09-26FMA RL 0, SRL 0; any 4$1,641,907.944 total; 0 since its plan
Jewett City boroughBoroughApproved, expires 2028-09-26FMA RL 0, SRL 0; any 0no Public Assistance recorded11 total; 1 since its plan
New London cityCityApproved, expires 2028-09-26FMA RL 1, SRL 2; any 17$1,277,944.2820 total; 0 since its planIncludes $0 for declarations not counted as hazard incidents (DR-4500-CT).
Norwich cityCityApproved, expires 2028-09-26FMA RL 0, SRL 1; any 16$4,015,572.0433 total; 0 since its planIncludes $389,501.73 for declarations not counted as hazard incidents (DR-4500-CT).
Stonington boroughBoroughApproved, expires 2028-09-26FMA RL 0, SRL 0; any 3$123,121.457 total; 0 since its plan
Bozrah townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 0$38,997.250 total; 0 since its plan
Colchester townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 0$723,510.9119 total; 0 since its planIncludes $21,745.25 for declarations not counted as hazard incidents (DR-4500-CT, EM-3342-CT).
East Lyme townTownApproved, expires 2028-09-26FMA RL 0, SRL 2; any 22$2,991,177.261 total; 0 since its plan
Franklin townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 1$144,890.4713 total; 3 since its plan
Griswold townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 0$588,918.992 total; 0 since its planIncludes $4,911.51 for declarations not counted as hazard incidents (EM-3342-CT).
Groton townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 6$1,472,530.044 total; 0 since its planIncludes $63,754.79 for declarations not counted as hazard incidents (DR-4500-CT).
Lebanon townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 0$595,089.0616 total; 0 since its planIncludes $48,899.48 for declarations not counted as hazard incidents (DR-4500-CT).
Ledyard townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 3$552,582.450 total; 0 since its planIncludes $36,059.73 for declarations not counted as hazard incidents (DR-4500-CT).
Lisbon townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 0$130,209.520 total; 0 since its plan
Montville townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 2$884,066.234 total; 1 since its planIncludes $47,986.12 for declarations not counted as hazard incidents (DR-4500-CT).
North Stonington townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 2$1,958,014.149 total; 2 since its planIncludes $27,389.76 for declarations not counted as hazard incidents (DR-4500-CT).
Preston townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 0$201,732.334 total; 0 since its plan
Salem townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 0$221,664.537 total; 0 since its planIncludes $4,254 for declarations not counted as hazard incidents (DR-4500-CT).
Sprague townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 0no Public Assistance recorded0 total; 0 since its plan
Stonington townTownApproved, expires 2028-09-26FMA RL 0, SRL 1; any 16$1,049,272.037 total; 0 since its planIncludes $21,435.06 for declarations not counted as hazard incidents (DR-4500-CT).
Waterford townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 10$2,281,796.623 total; 0 since its planIncludes $101,996.52 for declarations not counted as hazard incidents (DR-4500-CT).
Windham townTownApproved, expires 2028-09-26FMA RL 0, SRL 0; any 0$365,677.8521 total; 1 since its planIncludes $5,316.84 for declarations not counted as hazard incidents (DR-4046-CT).

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.

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.

Connecticut planning regions have no county-level plan in FEMA data; see each town's plan dates in the region.

  • 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 plancounty-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$5,500,393,195n/a19,031$1,304,675n/a$13,0330.0237%
Cold Wave$58,856,813,032$166,311,192280,193$543$12,800$800,694under 0.0001%
Droughtn/a$61,375,390n/an/a$36,156n/a0.0589% (agriculture)NRI has no building exposure for this hazard; agriculture shown
Earthquake$101,922,982,793n/a280,430$1,690,321n/a$301,2970.00166%
Hail$58,884,661,758$166,311,192280,316$9,662$5,414$226,588under 0.0001%
Heat Wave$58,856,813,032$166,311,192280,193$1$18,036$1,055,278under 0.0001%
Hurricane$58,883,551,150$166,311,192280,307$20,338,070$1,324,276$640,5160.0345%
Ice Storm$58,374,657,487n/a277,074$273,533n/a$121,3710.000469%
Inland Flooding$58,686,222,875$6,518,76110,101$52,052,335$60$46,204n/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$2,018,040,323n/a9,830$10,100n/a$1,9960.0005%
Lightning$58,884,661,758n/a280,316$33,568n/a$642,963under 0.0001%
Strong Wind$58,884,661,758$166,311,192280,316$181,091$240$569,8090.000308%
Tornado$58,884,661,758$166,311,192280,316$1,197,966$2,943$323,0440.00203%
Tsunamin/an/an/an/an/an/aNRI publishes no building exposure for this county
Wildfire$6,020,609,069$30,404,92543,720$22,711$17$4,9610.000377%
Winter Weather$58,856,813,032$166,311,192280,193$29,116$68$170,688under 0.0001%

Totals since the plan: not available. Connecticut planning regions have no county-level plan in FEMA data; see each town's plan dates in the region.

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
Population280,316
Building value (total, not at risk)$58,884,661,758
Agriculture value (total, not at risk)$166,311,192
NRI risk rating (all hazards)Relatively Moderate
Expected annual loss, buildings and agriculture, all hazards$78,543,703
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)$4,918,442
Social vulnerability ratingRelatively Low
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)1Severe repetitive loss, FMA definition (44 CFR 77.2)6
Repetitive loss, NFIP insurance definition102Severe repetitive loss, NFIP insurance definition6

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 total161026102040
of which: East Lyme town0222222012
of which: Groton town0060603
of which: Montville town0020200
of which: New London city121721706
of which: North Stonington town0020200
of which: Norwich city011611601
of which: Stonington town011611606
of which: Waterford town001001006
of which: Groton city0040403
of which: Franklin town0010100
of which: Ledyard town0030301
of which: Stonington borough0030302
Statewide, no county in FEMA's file0090904

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
Groton city0901260040403
Jewett City borough0900980000000
New London city090100121721706
Norwich city090102011611601
Stonington borough0901930030302
Bozrah town0900940000000
Colchester town0900950000000
East Lyme town0900960222222012
Franklin town0901540010100
Griswold town0901730000000
Groton town0900970060603
Lebanon town0901550000000
Ledyard town0901570030301
Lisbon town0901720000000
Montville town0900990020200
North Stonington town0901010020200
Preston town0901390000000
Salem town0901560000000
Sprague town0901050000000
Stonington town090106011611606
Waterford town090107001001006
Windham town0901190000000

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 residential1381381037
2 to 4 unit residential0040402
other residential0000000
non-residential031731701
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 0 properties are FMA repetitive loss but not NFIP repetitive loss, and 101 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). Southeastern Connecticut Planning Region, CT: risk-assessment baseline packet, release 2026-10 (data as of 2026-09-30; Planning region FIPS 09180). Automated baseline. https://hazardplain.org/ct/09180/ 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: contact@hazardplain.org