COUNTY REPORT SC

Dorchester County, South Carolina

12 ZIP codes · Avg score 80/100 · Grade B · Updated 2026-06-04

Within Dorchester County, all 12 tracked ZIP codes show above-average drinking water safety — violations are infrequent and typically minor.

How Dorchester County Compares

Dorchester County80/100
South Carolina avg78/100
National avg68/100

How Dorchester County Compares

B
County Grade
80/100
Avg Safety Score
12
ZIP Codes
16
Water Systems

Dorchester County scores 2 points above the South Carolina state average (78/100) and 12 points above the national average (68/100).

Data: EPA SDWIS Last verified: 2026-06-04

B
County Grade
80
Avg Safety Score
12
ZIP Codes
Best ZIP: 29471 (95/100)
Lowest ZIP: 29447 (66/100)
$245K
Median Home Value
$2,040
Avg Remediation (83% of home value)

ZIP Code Risk Map

Water Quality Map: Dorchester County, South Carolina

Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.

A B C D F

Key Risk Factors

Health risk index: 12.8 (asthma 9.6%, diabetes 13.1%)

Estimated additional annual cost per homeowner: $2,933, driven primarily by sea_level

Infrastructure: 0.24% avg pipe failure probability

39.2% of homes built before 1978 (lead paint era)

County Health Indicators vs National Average

Asthma 9.6% (national: 8.9%)
Diabetes 13.1% (national: 10.5%)
Obesity 35.3% (national: 32.4%)

Black markers indicate national averages. Source: CDC PLACES, Census ACS.

Infrastructure Overview

1993
Median Build Year
39.2%
Pre-1978 Housing
24%
Pipe Failure Probability
0%
ZIPs at High Infra Risk
Moderate
Lead Pipe Risk

Sources: Census ACS (housing age), EPA SDWIS (infrastructure risk model), state bridge inspection data.

Compound Risk Breakdown

Estimated additional annual cost per homeowner: $2,933

Sea Level Rise $1,500/yr
Flood $1,183/yr
Energy Code Gap $143/yr

Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).

Housing Age Distribution

79,833 housing units in Dorchester County

Pre-1940 1%
1940–1959 2%
1960–1979 19%
1980–1999 29%
2000+ 48%

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 Dorchester County

$245K
Median Home Value
$2,040
Est. Remediation Cost
0.8%
of Home Value
Remediation as % of home value low burden

Remediation costs are relatively manageable for most homeowners in Dorchester 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 Dorchester County residents

Asthma 9.6% (US avg: 8.9%)
Diabetes 13.1% (US avg: 11%)
Obesity 35.3% (US avg: 32.4%)

Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.

Water Systems with Most Violations

Top 5 systems in Dorchester County ranked by EPA violation count.

# Water System Population Violations
1 DCWS ASHLEY PHOSPHATE (SC1820008) 26,076 16
2 Summerville Cpw (sc1810003) 81,750 16
3 Dcws Southern Palms (sc1850011) 1,494 16
4 Dcwa Knightsville (1820001) 40,141 15
5 Dcws/clay Field Drive (sc1850014) 1,648 15

16 total water systems serve Dorchester County.

All ZIP Codes in Dorchester County

12 ZIP codes tracked in Dorchester County.

# ZIP Code City Safety Score Grade Violations Home Value
1 29471 Reevesville 95 A 0 $116K
2 29484 Summerville 94 A 5 (4 health)
3 29448 Harleyville 91 A 4 (4 health) $186K
4 29472 Ridgeville 85 A 0 $246K
5 29420 North Charleston 83 B 1 $284K
6 29483 Summerville 81 B 5 (4 health) $303K
7 29456 Ladson 80 B 0 $244K
8 29485 Summerville 76 B 5 (4 health) $311K
9 29404 Charleston Afb 73 B 0
10 29477 Saint George 73 B 0 $75K
11 29433 Canadys 66 C 0
12 29447 Grover 66 C 0

Recommended Buyer Guides for Dorchester County

While many sites publish identical guide lists across every county they cover, the selection here changes by location — driven by the EPA, NSF, FEMA, and CDC datasets that describe the actual conditions documented for this jurisdiction in the federal record.

Overview

Dorchester County in South Carolina covers 12 ZIP codes with an average Home Safety Score of B (80/100).

5 of 12 ZIP codes have recorded EPA violations. 16 health-based violations have been documented.

← Back to South Carolina water quality report

Data Sources

Updated daily.

Frequently Asked Questions

Is water safe in Dorchester County?
Dorchester County receives a grade of B, indicating generally safe tap water across its 12 ZIP codes.
How many water systems serve Dorchester County?
Dorchester County is served by 16 public water systems that supply drinking water to residents across 12 ZIP codes.
What is the biggest environmental risk in Dorchester County?
The primary environmental risk factor in Dorchester County is sea_level. This contributes to an estimated additional annual cost of $2,933 per homeowner.
How old are homes in Dorchester County?
The median home build year in Dorchester County is 1993. 39.2% of homes were built before 1978, which means they may contain lead-based paint and older plumbing materials.
How does Dorchester County compare to South Carolina?
Dorchester County has an average water safety score of 80/100, which is above the South Carolina state average of 78/100.

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