Duncan, SC Water Safety: 63/100 (2026)
1 ZIP code · 2 water systems · Updated 2026-06-03
Across water systems in Duncan, safety results are uneven — a portion carry active or recent violations, while others meet federal standards without incident, placing the city in the middle tier for SC.
How Duncan Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Duncan Water
- Homes built before 1986: 23% — older plumbing may contain lead solder.
- Estimated remediation: $1,600 per household.
- CDC health risk index: 13.55 — above typical levels.
Who Supplies Your Water in Duncan
Throughout Duncan, SC, water comes from one of 2 primary utilities out of 2 total systems — independent providers with different rate structures, infrastructure, and compliance records that vary across the service territory.
Overview
We track water quality and home safety data for 1 ZIP code in Duncan, South Carolina (population ~18,260), covering 2 community water systems serving approximately 140,861 people region-wide.
No EPA violations recorded across any ZIP codes in Duncan — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Duncan: C (63/100)
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
Duncan water systems draw from: Surface water.
Lead & Copper
- Lead data: not yet available for Duncan
- 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 |
|---|---|---|---|
| 29334 | C | SJWD MIDDLE TYGER WTP (4220006) | 87,259 |
All ZIP Codes in Duncan
- 29334 [C]
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.
Health Outcomes in Duncan
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
Housing & Infrastructure in Duncan
Housing age data helps assess potential lead pipe and infrastructure risks. Newer housing stock generally means lower plumbing-related contamination risk.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Post-1986 construction is where the lower lead-solder risk lives, because that's when the federal ban on lead solder in plumbing took effect. In Duncan, where the median build year is 2006, the housing stock falls broadly on the newer side of that threshold — a distribution that moderates aggregate plumbing-era risk compared to older housing markets.
Most homes in Duncan were built after 1986, reducing the risk of lead contamination from plumbing. Older homes should still be tested.
Source: U.S. Census Bureau ACS B25034.
Cost Context: What Remediation Means for Duncan Homeowners
In Duncan, the equity impact of remediation is proportionally small — not the kind of financial commitment that rises to the level of a genuine planning constraint, but a minor share of what most properties here are worth.
Remediation costs in Duncan are relatively low compared to home values. The $800–$2,600 estimated range is a small fraction of median property value. Home values are 30% above the South Carolina average.
Lead Exposure Risk for Children in Duncan
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.
23% of housing in Duncan predates the federal action against lead solder — a contained share — and aggregate readings stay beneath the regulatory benchmark. Lead therefore sits in a quiet position on the local water-quality picture, with single-home draws as the standard tool for confirming any one address.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Duncan
The NFIP claim record for Duncan — 4 filed incidents — reflects genuine, recurring flood exposure rather than an isolated event or two. When a community accumulates flood claims at this volume and carries 100% of its ZIP codes inside FEMA-designated zones, flood history starts to factor into water quality planning in ways it doesn't for lower-exposure areas. Flooding introduces specific contamination pathways — runoff overwhelming treatment facility intake, surface water infiltrating private wells, and pressure disruptions in distribution systems allowing backflow — all of which become more relevant as flood frequency increases.
Duncan has a moderate flood history with 4 FEMA claims averaging $189 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>$1,600</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.
What You Can Do in Duncan
- Test your water at home. City-level data shows averages — your tap may differ. NSF-certified test kits cost $20-40 and give results in days.
- Install a certified water filter. An NSF-certified pitcher or under-sink filter removes most common contaminants.
- Check your home's plumbing. Homes built before 1986 may have lead solder in pipes. A licensed plumber can assess your risk.
Deep Dive Reports
Detailed analysis for Duncan, SC