95 flood insurance claims·$669,305 paid·8 federal flood & hurricane disasters
Share of the whole county outline, rivers and lakes included; parts FEMA hasn’t mapped count as zero.
Shaded areas are FEMA’s mapped flood hazard zones in and around Coos County, New Hampshire. Zoomed out they are simplified; at street level the map switches to FEMA’s exact layer. Tap anywhere to check that spot, or search an address above.
River flooding and flash flooding dominate the flood character of Coos County, with NOAA records showing 74 flood events, 60 flash flood events, and 4 tropical storm events over the last 30 years. Recent impacts include flash flooding on July 10, 2024, when the remnants of Tropical Storm Beryl combined with a Great Lakes low pressure system following three previous days of heavy rain north of the White Mountains. This 36-hour period dropped 3 to 5 inches of rain, saturating the ground and causing significant runoff.
National Flood Insurance Program claims data indicates that Zone A properties experienced the highest claim frequency with 51 claims averaging a $10,349 payout and an average recorded water depth of 9 inches. Properties located in Zone X recorded an average payout of $17,213 with an average water depth of 32 inches, while Zone X unshaded properties averaged $27,922 per claim with an average recorded water depth of 0 inches. Zone X shaded properties averaged a $5,301 payout with an average depth of 16 inches, and Zone Unknown claims averaged $3,878 with an average depth of 2 inches. Homeowners, real estate agents, and journalists should pay particular attention to properties in Zone A and Zone X, where claims and recorded water depths indicate substantial flood exposure.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
22% of Coos County’s flood insurance claims were on properties rated outside FEMA’s high-risk zones.
65 NFIP claims with a recorded rated flood zone, 1978 to date. The zone is the one FEMA used to rate that policy, which may not match today’s map. Source: OpenFEMA NFIP claims.
In flood insurance claims here that reported a flood depth, the average was 11 inches.
Drawn to scale against an 80-inch door. Even a few inches soaks flooring, the bottom of the drywall and anything plugged in near the floor.
Average of the depths reported on claims (zero and implausible values left out); FEMA’s record doesn’t say exactly where each depth was measured. Source: OpenFEMA NFIP claims.
The worst year was 1998, with 16 claims and $162,526 paid, the year of Severe Ice Storm, Rains and High Winds.
Bar height is scaled by square root so ordinary years stay visible next to the worst one. NFIP claims by year of loss. Source: OpenFEMA.
72 NOAA storm reports from Coos County describe what happened, in the words of the forecasters who covered it. Read the New Hampshire flood stories →
28 federal disaster declarations since 1973, 8 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Storm And Flooding | Jul 10, 2024 |
| Severe Storm And Flooding | Dec 17, 2023 |
| Severe Storms And Flooding | Jul 9, 2023 |
| Severe Storm And Flooding | Dec 22, 2022 |
| Severe Storm And Flooding | Oct 29, 2017 |
| Severe Storms And Flooding | Jul 1, 2017 |
| Hurricane Sandy | Oct 26, 2012 |
| Severe Storm | Oct 29, 2011 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
138 since 1996: 60 flash floods and 74 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flash Flood | Jul 11, 2024 | — |
| Flash Flood | Jul 10, 2024 | — |
| Flash Flood | Jul 6, 2024 | — |
| Flash Flood | Jul 18, 2023 | — |
| Flood | Dec 18, 2023 | $300,000 |
| Flood | Dec 18, 2023 | — |
| Flash Flood | Dec 18, 2023 | — |
| Flash Flood | Dec 18, 2023 | $500,000 |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flash Flood · Jul 11, 2024. On July 10th the remnants of Tropical Storm Beryl phased with a low pressure system out of the Great Lakes to bring multiple rounds of heavy rainfall to northern New England, including Maine and New Hampshire. The previous 3 days had brought a swath of heavy rain just north of the White Mountains, saturating the ground and making it ideal for runoff. During the roughly 36 hour period, 3 to as much as 5 inches of r…
Flash Flood · Jul 10, 2024. On July 10th the remnants of Tropical Storm Beryl phased with a low pressure system out of the Great Lakes to bring multiple rounds of heavy rainfall to northern New England, including Maine and New Hampshire. The previous 3 days had brought a swath of heavy rain just north of the White Mountains, saturating the ground and making it ideal for runoff. During the roughly 36 hour period, 3 to as much as 5 inches of r…
Flash Flood · Jul 6, 2024. A slow moving cold front triggered scattered thunderstorms across northern New Hampshire on July 6th. Repeating storms across Grafton and Coos Counties produced locally heavy rainfall resulting in localized areas of road washouts.
Flash Flood · Jul 18, 2023. Scattered showers and thunderstorms with heavy rainfall developed across the White Mountains and areas northward on the afternoon of the 18th. Moist air supported torrential rainfall rates between 2 to 3 inches an hour, all of which fell over saturated soils. Localized flash flooding resulted where storms trained over the same locations.
National Weather Service narratives, lightly trimmed. Source: NOAA Storm Events Database.
Every colour on the map above is a place on this drawing: where the ground sits relative to the flood FEMA plans for.
If a building in Coos County is in a high-risk zone (A or V) and its mortgage comes from a federally regulated or insured lender, or is federally backed, flood insurance is required.
Outside those zones it is optional, and often worth having: from 2014 to 2024 nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area. Since Risk Rating 2.0, NFIP premiums are set for each building, so the only reliable price is a quote: FloodSmart.gov or a local agent.