Rockingham County, New Hampshire
41 ZIP codes · Avg score 69/100 · Grade C · Updated 2026-06-04
Unlike top-rated counties, Rockingham County's 41 ZIP codes carry a fair number of documented violations — chlorine compliance and disinfection byproduct limits are the categories most often cited in recent data.
How Rockingham County Compares
How Rockingham County Compares
Rockingham County scores 5 points above the New Hampshire state average (64/100) and 1 points above the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-04
ZIP Code Risk Map
Water Quality Map: Rockingham County, New Hampshire
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 11.7 (asthma 10%, diabetes 9.1%)
Estimated additional annual cost per homeowner: $1,601, driven primarily by flood
Infrastructure: 0.367% avg pipe failure probability, 24% of ZIPs at high risk
56.1% of homes built before 1978 (lead paint era)
Violation History (2021–2025)
↓ Improving trendEPA violation counts by year across Rockingham County water systems. Health-based shown in red, total in blue.
Peak year: 2023 with 25 violations. Past 5 years: 59 total (59 health-based). Health-based violations are declining versus the prior 2-year window.
Source: EPA SDWIS historical violations. Data may lag 6–12 months for the most recent year.
County Health Indicators vs National Average
Black markers indicate national averages. Source: CDC PLACES, Census ACS.
Infrastructure Overview
Sources: Census ACS (housing age), EPA SDWIS (infrastructure risk model), state bridge inspection data.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $1,601
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
132,393 housing units in Rockingham County
Source: U.S. Census Bureau ACS B25034 (Year Structure Built).
Water Safety Affordability
How much it costs to fix water issues relative to home values in Rockingham County
Remediation costs are relatively manageable for most homeowners in Rockingham County, representing a small fraction of property value.
Remediation includes water filtration, lead abatement, radon mitigation, and flood protection where applicable. Source: Census ACS, EPA SDWIS.
Health Outcomes vs National Average
CDC PLACES data for Rockingham County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water Systems with Most Violations
Top 5 systems in Rockingham County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Aquarion Water/nh | 34,000 | 26 |
| 2 | Hemlock Haven | 207 | 22 |
| 3 | Thornhill Condos | 175 | 19 |
| 4 | Montrose Condos | 210 | 18 |
| 5 | HAMPSTEAD AREA WATER | 6,953 | 15 |
106 total water systems serve Rockingham County.
All ZIP Codes in Rockingham County
41 ZIP codes tracked in Rockingham County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 3841 | Hampstead | 83 | B | 1 | $466K |
| 2 | 3802 | Portsmouth | 82 | B | 3 (1 health) | — |
| 3 | 3803 | Portsmouth | 82 | B | 3 (1 health) | — |
| 4 | 3804 | Portsmouth | 82 | B | 3 (1 health) | — |
| 5 | 3843 | Hampton | 82 | B | 5 (1 health) | — |
| 6 | 3857 | Newmarket | 78 | B | 0 | $385K |
| 7 | 3801 | Portsmouth | 77 | B | 3 (1 health) | $648K |
| 8 | 3053 | Londonderry | 76 | B | 5 (2 health) | $464K |
| 9 | 3032 | Auburn | 75 | B | 0 | $548K |
| 10 | 3036 | Chester | 75 | B | 1 | $480K |
| 11 | 3087 | Windham | 75 | B | 0 | $685K |
| 12 | 3827 | East Kingston | 75 | B | 0 | $537K |
| 13 | 3844 | Hampton Falls | 75 | B | 0 | $665K |
| 14 | 3856 | Newfields | 75 | B | 0 | $618K |
| 15 | 3873 | Sandown | 75 | B | 0 | $402K |
| 16 | 3261 | Northwood | 73 | B | 2 | $356K |
| 17 | 3833 | Exeter | 72 | B | 2 | $456K |
| 18 | 3858 | Newton | 72 | B | 0 | $429K |
| 19 | 3037 | Deerfield | 70 | B | 0 | $390K |
| 20 | 3038 | Derry | 70 | B | 1 | $382K |
| 21 | 3044 | Fremont | 70 | B | 0 | $405K |
| 22 | 3077 | Raymond | 70 | B | 8 (3 health) | $343K |
| 23 | 3290 | Nottingham | 70 | B | 1 | $419K |
| 24 | 3819 | Danville | 70 | B | 4 (2 health) | $407K |
| 25 | 3826 | East Hampstead | 70 | B | 4 (2 health) | $486K |
| 26 | 3854 | New Castle | 70 | B | 1 | $1613K |
| 27 | 3874 | Seabrook | 70 | B | 6 | $435K |
| 28 | 3079 | Salem | 69 | C | 5 (1 health) | $439K |
| 29 | 3842 | Hampton | 67 | C | 5 (1 health) | $492K |
| 30 | 3811 | Atkinson | 66 | C | 9 (5 health) | $489K |
| 31 | 3865 | Plaistow | 65 | C | 4 (4 health) | $382K |
| 32 | 3040 | East Candia | 63 | C | 0 | — |
| 33 | 3073 | North Salem | 63 | C | 0 | — |
| 34 | 3859 | Newton Junction | 63 | C | 0 | — |
| 35 | 3870 | Rye | 59 | C | 1 (1 health) | $928K |
| 36 | 3848 | Kingston | 56 | C | 2 (2 health) | $442K |
| 37 | 3885 | Stratham | 55 | C | 9 (8 health) | $600K |
| 38 | 3041 | East Derry | 53 | D | 0 | — |
| 39 | 3042 | Epping | 50 | D | 9 (8 health) | $421K |
| 40 | 3862 | North Hampton | 50 | D | 0 | $612K |
| 41 | 3871 | Rye Beach | 50 | D | 0 | $1504K |
Recommended Buyer Guides for Rockingham County
If FEMA records flag flood-top-risk status or EPA samples show PFAS exceedances, the matching logic lifts emergency-water and PFAS-rated filtration into the recommendations — federal data drives the order, not retailer arrangements.
- Best Water Filters for Lead — Lead above EPA action level in 1 ZIP code
- Best Lead Paint Test Kits — 56.1% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
- Best Sump Pumps — Flood is the top compound risk factor
- Best Mold Test Kits — Flood-driven moisture and mold risk
Deep Dive Reports
Detailed analysis for Rockingham County, New Hampshire
Overview
Rockingham County in New Hampshire covers 41 ZIP codes with an average Home Safety Score of C (69/100).
25 of 41 ZIP codes have recorded EPA violations. 44 health-based violations have been documented.
← Back to New Hampshire water quality report
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Home values: U.S. Census Bureau ACS (median estimates by ZCTA)
Updated daily.