Updated May 2026
Flood Risk in Middlesex, MA
Middlesex, MA has a Flood Risk Score of 17/100 (Grade A), ranking #421 of 3,277 counties nationwide. The risk level is Low. There have been 32 NFIP flood-insurance claims totaling $383,172 in payouts, with 13 federal disaster declarations on record.
Key Data
What the Grade Means Here
Middlesex sits in the lowest-risk tier in the FEMA dataset — composite score 17, ranked #421 of 3,277 counties (where #1 is the riskiest). The county has logged 32 NFIP flood-insurance claims and 13 federal flood-related disaster declarations to date. An A grade does not mean zero risk: flash floods, sewer backups, and rare extreme storms can still cause loss, and FEMA reports more than 25% of all NFIP payouts originate from properties outside Special Flood Hazard Areas.
Within Massachusetts, Middlesex carries flood risk roughly typical of the state, where the average composite score is 13. The county ranks #2 of 15 state-internally. The full Massachusetts state profile shows how every county within the state compares.
What's Driving the Risk Score?
The single biggest driver of the composite score in this county is year-over-year trend (15% of the formula, factor score 67). For Middlesex, that means the year-over-year trend in flood losses is contributing meaningfully — this is a county where loss has been climbing in recent years, not just historically high.
The trend factor of 67 of 100 indicates flood-loss volume has been climbing in this county relative to its own history. That can reflect either climate-driven shifts in precipitation patterns, new development extending into flood-prone areas, or both.
Score Breakdown
| Factor | Score | Weight |
|---|---|---|
| Claims Density | 0 | 40% |
| Disaster Frequency | 28 | 25% |
| Claim Severity | 0 | 20% |
| Year-over-Year Trend | 67 | 15% |
How This Score Is Calculated
The composite is a weighted average of four FEMA-derived factors. Source data comes from the public FEMA flood-mapping program via the OpenFEMA API. For property-level decisions, layer this with the parcel's FEMA Flood Insurance Rate Map zone and recent crest readings from USGS Water Data. Full math: methodology page.
Frequently Asked Questions
What is the flood risk in Middlesex, MA?
Middlesex, MA has a Flood Risk Score of 17/100 (Grade A), ranking #421 of 3,277 counties nationwide. The risk level is Low. There have been 32 NFIP flood-insurance claims totaling $383,172 in payouts, with 13 federal disaster declarations on record.
Is flood insurance required in Middlesex?
Federal law requires flood insurance for any property in a Special Flood Hazard Area (FEMA Zone A or V) financed by a federally regulated lender. Middlesex's county-wide composite score is 17 (Grade A), which is a county aggregate — your specific parcel's flood-zone designation comes from the FEMA Flood Insurance Rate Map (FIRM) at fema.gov/flood-maps. Even when not legally required, NFIP coverage is often available for a few hundred dollars a year in moderate- and low-risk zones, and FEMA reports more than 25% of all NFIP claims come from outside high-risk zones.
What is driving the flood risk score in Middlesex?
The single biggest driver of the composite score in this county is year-over-year trend (15% of the formula, factor score 67). For Middlesex, that means the year-over-year trend in flood losses is contributing meaningfully — this is a county where loss has been climbing in recent years, not just historically high.
Is flood risk increasing or decreasing in Middlesex?
The trend factor of 67 of 100 indicates flood-loss volume has been climbing in this county relative to its own history. That can reflect either climate-driven shifts in precipitation patterns, new development extending into flood-prone areas, or both.
How does Middlesex compare to other counties in Massachusetts?
Within Massachusetts, Middlesex carries flood risk roughly typical of the state, where the average composite score is 13. The county ranks #2 of 15 state-internally.
Where does this data come from?
Every figure on this page comes from FEMA's public OpenFEMA API — the DisasterDeclarationsSummaries v2 endpoint (federally declared flood-related disasters) and the FimaNfipClaims endpoint (individual NFIP flood-insurance claims aggregated by county FIPS code). Both are public-domain U.S. government work. Real-time stream-gauge readings that complement these federal aggregates live at USGS Water Data. Last updated 2026-05-16.
Middlesex, MA has a Flood Risk Score of 17/100 (Grade A), ranking #421 of 3,277 counties nationwide. The risk level is Low. There have been 32 NFIP flood-insurance claims totaling $383,172 in payouts, with 13 federal disaster declarations on record.
This answer pulls from FEMA OpenFEMA datasets including the National Flood Hazard Layer and NFIP claims, the authoritative federal source for U.S. flood risk, NFIP claims, and disaster declarations. The headline number above is the direct answer; what follows is the additional context most readers need to use the answer for a real decision rather than just a fact lookup.
For readers turning this answer into action: cross-reference against the underlying FEMA OpenFEMA datasets including the National Flood Hazard Layer and NFIP claims record before acting on time-sensitive decisions. The site renders the data as it was published; subsequent revisions can shift the picture, and the live federal data is always the authoritative current reference.