People move to Western Massachusetts partly because it does not appear on the list of places that get destroyed. No hurricanes coming ashore, no wildfire season, no earthquake fault anybody talks about. That instinct is broadly right, and it is wrong about one thing in a way that costs people real money.
The federal government models eighteen natural hazards for every county and puts a dollar figure on the expected annual loss from each. Across these four counties the total comes to $218,606,856 a year. Of that, 72% is a single hazard: riverine flooding.
The Answer Is Flooding, And It Is Not Close
Riverine Flooding accounts for $156,808,260 of expected annual loss here. The next largest, hurricane, comes to $20,929,308, roughly 7 times less.
This is not a surprise if you look at a map. Four counties organised around rivers, with the Connecticut running the length of the region and steep tributaries feeding it out of the hills. The towns are where the rivers are, because that is where the mills were, and the housing stock sits on the floodplain that made those mills possible.
It is also the hazard people underprepare for most, because ordinary homeowner's insurance excludes flood entirely. Everything else on the list below is broadly covered by the policy you will buy anyway. The one that dominates the loss figure is the one you have to buy separately and are not required to, and a quarter of paid flood claims in this region came from properties outside the high-risk zone.
Every Hazard, Ranked
Expected Annual Loss by Hazard, All Four Counties
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Modelled average annual loss from each of the eighteen hazards in the federal risk index, summed across Berkshire, Franklin, Hampden and Hampshire counties. Losses combine buildings, population and agriculture. These are long-run modelled averages rather than a prediction for any particular year, and hazards showing none modelled do not occur in this region.
| Hazard | Expected Annual Loss | Share of Total |
|---|---|---|
| Riverine Flooding | $156,808,260 | 71.7% |
| Hurricane | $20,929,308 | 9.6% |
| Cold Wave | $9,922,663 | 4.5% |
| Earthquake | $7,220,638 | 3.3% |
| Tornado | $7,029,431 | 3.2% |
| Strong Wind | $5,255,500 | 2.4% |
| Heat Wave | $3,801,353 | 1.7% |
| Ice Storm | $2,450,636 | 1.1% |
| Lightning | $1,901,660 | 0.9% |
| Hail | $1,747,728 | 0.8% |
| Drought | $945,670 | 0.4% |
| Winter Weather | $452,755 | 0.2% |
| Wildfire | $80,392 | 0.0% |
| Landslide | $56,711 | 0.0% |
| Avalanche | $4,152 | 0.0% |
| Coastal Flooding | None modelled | 0% |
| Tsunami | None modelled | 0% |
| Volcanic Activity | None modelled | 0% |
What These Columns Mean
- Hazard
- One of the eighteen natural hazards the federal index models.
- Expected Annual Loss
- Modelled average annual loss across all four counties combined, in buildings, population and agriculture. A long-run average, not a forecast for any given year.
- Share of Total
- That hazard's share of all expected annual loss in the region.
Cite: RE413. “Expected Annual Loss by Hazard, All Four Counties.” Updated August 5, 2026. https://www.re413.com/news/natural-disasters-western-mass/, underlying sources at https://www.re413.com/sources/.
15 of the eighteen hazards produce any modelled loss here at all. The other 3 are coastal flooding, tsunami, volcanic activity, which is exactly what you would hope for in a landlocked New England region and is worth printing rather than hiding. A national index carries hazards that simply do not apply, and showing the zeroes is what makes the rest of the table credible.
The Ratings Are Percentiles, Which Trips Everybody Up
Each county gets a composite rating, and here they are with the number that makes them interpretable.
Risk Rating and Exposure by County
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The federal index's composite risk rating, modelled expected annual loss, total building value exposed and the community resilience rating for each county. The risk rating is a national percentile: a county rated Relatively Moderate is moderate against all United States counties, which include places with active fault lines and annual hurricane landfall.
| County | Risk Rating | Expected Annual Loss | Building Value Exposed | Community Resilience |
|---|---|---|---|---|
| Hampden | Relatively Moderate | $106,696,441 | $81.3bn | Relatively High |
| Berkshire | Relatively Moderate | $51,762,098 | $30.1bn | Very High |
| Hampshire | Relatively Low | $37,274,376 | $31.7bn | Very High |
| Franklin | Relatively Low | $22,873,942 | $14.7bn | Very High |
What These Columns Mean
- County
- One of the four western counties.
- Risk Rating
- The federal index's composite rating. It is a percentile against all United States counties, so 'Relatively Moderate' means moderate compared with the whole country, not moderate in ordinary language.
- Expected Annual Loss
- Modelled average annual loss for the county across all hazards.
- Building Value Exposed
- Total value of buildings in the county. Read the loss column against this: a bigger county has more to lose.
- Community Resilience
- The index's rating of the county's capacity to prepare for and recover from a hazard event. Higher is better.
Cite: RE413. “Risk Rating and Exposure by County.” Updated August 5, 2026. https://www.re413.com/news/natural-disasters-western-mass/, underlying sources at https://www.re413.com/sources/.
Two things to understand before you read anything into those ratings.
First, they are national percentiles. A rating of "Relatively Moderate" means moderate compared with every county in the United States, a set that includes places on active faults and places that take a hurricane most years. Moderate on that scale is a long way from alarming.
Second, expected annual loss scales with how much there is to lose. The county with the highest modelled loss is also the one with by far the most building value and the most people. That is arithmetic, not danger. A house in the county with the biggest number is not more exposed than a house in the county with the smallest; there are simply more houses.
Normalise for it and the region looks unremarkable: about $1,385 of expected annual loss for every million dollars of building value. The community resilience ratings, which measure capacity to prepare and recover, come out high or very high across all four counties.
What This Should Change About A Purchase
- Take flood seriously and treat everything else as ordinary. The loss table is not subtle. If you do one thing after reading this, price flood cover for the specific address rather than assuming the zone map settles it.
- Ask about the winter hazards, which are the ones that actually interrupt life here. Ice storms and cold waves rarely destroy a house and routinely take the power out for days. A generator, a transfer switch and a wood stove are common in this region for a reason.
- Do not read a county rating as a statement about a property. Whether your house floods depends on where it sits relative to a watercourse and a culvert, which is a question about that lot. Look the address up rather than the county.
- If there is an impoundment upstream, understand what a hazard classification means before you draw a conclusion from it. It describes the consequence of a failure, not its likelihood, and the distinction is the whole thing.
The broad instinct that brought you here is correct. This is a geologically and meteorologically calm part of the country. It has one exposure that matters, it is the one the insurance industry excludes by default, and it is entirely manageable if you know about it before you sign.
Sources
- Federal Emergency Management Agency. National Risk Index: composite risk rating, expected annual loss by hazard, exposed building value and community resilience, at county level.
"Figures through" is the period the publisher's data describes; "checked" is only when we last asked. The full sourcing: sources and method.