Storms, floods and disasters in South Dennis
South Dennis isn’t graded for hazard risk: South Dennis is a Census area inside a town, graded with the town. Flood insurance has paid 2 claims here since 1998.
What South Dennis faces
Each hazard’s share of the building damage FEMA expects here, and how its rate compares with the rest of the country.
River and rain flooding
Hurricanes
Coastal flooding
Shares are of FEMA’s expected building damage, the measure the grade uses; ranks compare each hazard’s building-damage rate with all 85,154 U.S. census tracts. In FEMA’s terms, river and rain flooding is FEMA’s “Inland Flooding” (rivers and streams overflowing their banks, or rain overwhelming drainage). FEMA defines coastal flooding as high or rising tides and storm surge, so surge damage is counted there. Drought isn’t listed: FEMA counts its losses in crops only.
Does South Dennis flood? Rarely: 2 flood claims since 1998
Every paid claim on a federal flood insurance policy in South Dennis, from FEMA’s records.
- The March 2010 nor’easter1 claim · $604
South Dennis isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Barnstable County.The storms South Dennis remembers
None of the 18 disasters declared for Barnstable County shows FEMA aid or repair money reaching South Dennis itself in FEMA’s records, so these are its biggest flood-claim years.
- 19981 flood claims paidNo declaration for the county that year
- 20101 flood claims paidThe year of Hurricane Earl, declared for Barnstable County
Barnstable County has had 18 natural disasters declared by the President since 1953, most often hurricanes and tropical storms, then winter storms. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees.
Old photos of South Dennis after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the South Dennis archive →South Dennis and its neighbors
How expected damage per building compares across the town line. Tap a town to see its hazards.
| Town | Hazard risk | Mostly (buildings) | Flood claims |
|---|---|---|---|
| Dennis | B−less damage than 50% | river and rain flooding | 200 |
| Yarmouth | B−more damage than 53% | river and rain flooding | 169 |
| East Dennis | — | a Census area inside a town; graded with the town | |
| West Dennis | — | a Census area inside a town; graded with the town | |
| South Yarmouth | — | a Census area inside a town; graded with the town | |
| Yarmouth Port | — | a Census area inside a town; graded with the town | |
| Dennis Port | — | a Census area inside a town; graded with the town | |
Hazard risk = FEMA’s expected yearly building damage per dollar of building value, vs. the 21,298 U.S. towns we grade; the map is shaded by fifths of the same scale. Flood claims = paid federal flood insurance claims on record.
Get ready for what South Dennis faces
A short kit for the hazards that drive the building damage here, what to check before you buy, and where neighbors get alerts.
- Turn around at flooded roads: a foot of moving water can carry off a car.
- Flood insurance usually takes 30 days to start, so buy it before the forecast.
- Keep papers and medicines up high, in a grab-and-go bag.
- The season runs June through November and peaks from mid-August to mid-October.
- Bring in porch furniture and anything the wind can throw.
- Fill the gas tank and charge phones before the storm arrives.
- Know your evacuation zone and the way off the coast.
- Storm surge comes fast: leave when you’re told, not when the water arrives.
- Move cars to high ground before king tides and nor’easters.
- Look up the address on FEMA’s flood map.
- Ask the seller or landlord whether it has ever flooded, and what flood insurance costs there.
- Get a flood insurance quote early: policies usually start 30 days after you buy.
Know where neighbors sign up for alerts? Add it to the Handbook so everyone has it.
Questions about natural hazards in South Dennis
Does South Dennis flood?
Flood insurance has paid 2 claims in South Dennis since 1998, $1K in all. The most claims came from March 2010 Nor'easter (1).
Is South Dennis in a flood zone?
Flood zones are drawn street by street, so the answer depends on the address: look it up on FEMA’s flood map. In Barnstable County, 40% of homes in mapped flood zones carry federal flood insurance, and 5.4% of all homes do.
How much is flood insurance in South Dennis?
FEMA’s Community Rating System list shows no discount for South Dennis’ flood program. Premiums depend on the building; policies usually start 30 days after you buy, so get a quote early.
What was the biggest storm in South Dennis?
By flood claims, March 2010 Nor'easter: 1 paid, $604.
Storm stories
Memories, warnings and help from neighbors in South Dennis.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where South Dennis’ residents lived in the 2020 census; OpenFEMA: NFIP redacted claims, multiple-loss properties, community status book and residential penetration rates, housing assistance (owners and renters), public assistance funded projects, hazard mitigation properties and disaster declarations. Homes: Census ACS 2020–24. Preparedness tips: Ready.gov. FEMA’s model is an average of expected damage, not a forecast. How hazard risk is graded.