Harwich, MA Water Safety: 78/100 (2026)
1 ZIP code · 2 water systems · Updated 2026-06-03
The water systems supplying Harwich show a track record of above-average compliance with federal standards — consistently among the better performers in MA.
How Harwich Compares
Data: EPA SDWIS Last verified: 2026-06-03
Key Facts for Harwich Residents
- Average lead level: 0.002 mg/L.
- Homes built before 1986: 61% — older plumbing may contain lead solder.
- Estimated remediation: $2,200 per household.
- CDC health risk index: 12.93 — above typical levels.
Harwich's Water Providers
Federal drinking water records identify 2 systems in Harwich, MA. The leading 2 providers serve the largest share of residential connections, each operating as a separate entity with its own rate authority, infrastructure management, and EPA compliance obligations — so service conditions are not uniform city-wide.
Overview
We track water quality and home safety data for 1 ZIP code in Harwich, Massachusetts (population ~11,060), covering 2 community water systems serving approximately 74,144 people region-wide.
No EPA violations recorded across any ZIP codes in Harwich — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Harwich: B (78/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Harwich water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0020 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 2 (Moderate Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 02645 | B | Harwich Water Department | 39,144 |
All ZIP Codes in Harwich
- 02645 [B]
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.
Harwich Community Health Snapshot
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Harwich Infrastructure Age
With 61% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Harwich's housing stock is predominantly older, with a median build year of 1989 that reflects decades of construction before federal plumbing standards were tightened. The 1986 ban on lead solder and the pre-1970 era of lead service lines are both relevant benchmarks here — a significant share of the residential inventory predates one or both of those cutoffs, creating an elevated baseline for plumbing-related lead risk that aggregate water quality data may not fully reflect at the household level.
Over half of homes in Harwich were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
How Remediation Costs Compare in Harwich
When remediation costs are measured against Harwich home values, the resulting ratio is in the low tier — addressing documented water and safety issues here claims only a minor fraction of typical equity, and most homeowners are in a position where the financial commitment is straightforward rather than a material burden on their household budget.
Remediation costs in Harwich are relatively low compared to home values. The $1,200–$3,300 estimated range is a small fraction of median property value. Home values are 3% above the Massachusetts average.
Harwich: Lead Risk & Vulnerable Populations
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
Before the federal solder ban, lead solder was a routine plumbing material, and 61% of the Harwich inventory was built in that earlier era — a share large enough to move household-level reads onto the standard list.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Harwich: Flood History & Water Damage Risk
Multiple flood events have been recorded for Harwich through the NFIP — 11 claims in total, with 100% of ZIP codes in FEMA-designated zones — pointing to a flood exposure profile that merits inclusion in a water quality assessment without reaching high-severity planning territory.
Harwich has a moderate flood history with 11 FEMA claims averaging $31,246 per payout. 100% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$2,200</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
Deep Dive Reports
Detailed analysis for Harwich, MA