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State water index

Delaware water hardness

Search 37 indexed communities and 48 ZIP profiles, then compare the underlying utility, source, distance, and reporting context.

Median indexed hardness

55PPM

Soft

Indexed range 47.3–82.4 PPM

ZIP profiles
48
Cities
37
Matched utilities
162
Counties
3

Understanding Delaware

Why local comparisons matter here

Delaware lies almost entirely on the Atlantic Coastal Plain, with communities relying on groundwater aquifers, surface supplies, or purchased water in a small but varied service landscape.

In this index, soft is the largest category, covering 34 of 48 profiles with hardness data. The state median is 55 PPM, but the full indexed range is 47.3–82.4 PPM.

State distribution

Hardness across indexed ZIPs

Counts describe published ZIP profiles, not a population-weighted statewide sample.

Soft · 0–60 PPM34
Moderately hard · 61–120 PPM14
Hard · 121–180 PPM0
Very hard · 181+ PPM0

Evidence coverage

What the current records support

Hardness estimate
100%
Lead 90th percentile
100%
Copper 90th percentile
44%

0

Low-confidence hardness profiles

0

Nearest site more than 25 miles away

Reported source water

Utility source mix

Groundwater
157
Surface water
5

City directory

Explore Delaware by city

Search by city or county, then sort by name, hardness, or ZIP coverage.

37 cities · 48 ZIP profiles

37 cities found

Page 1 of 2

Bear

New Castle County · 1 ZIP

79PPM

Single indexed valueNo active flag

Bethany Beach

Sussex County · 1 ZIP

54PPM

Single indexed valueNo active flag

Bridgeville

Sussex County · 1 ZIP

54PPM

Single indexed valueNo active flag

Cheswold

Kent County · 1 ZIP

54PPM

Single indexed valueNo active flag

Clayton

Kent County · 1 ZIP

57PPM

Single indexed valueNo active flag

Dagsboro

Sussex County · 1 ZIP

54PPM

Single indexed valueNo active flag

Delmar

Sussex County · 1 ZIP

59PPM

Single indexed valueNo active flag

Dover

Kent County · 3 ZIPs

54PPM

Range 51.7–53.7No active flag

Ellendale

Sussex County · 1 ZIP

49PPM

Single indexed valueNo active flag

Fenwick Island

Sussex County · 1 ZIP

54PPM

Single indexed valueNo active flag

Frederica

Kent County · 1 ZIP

53PPM

Single indexed valueNo active flag

Georgetown

Sussex County · 1 ZIP

53PPM

Single indexed valueNo active flag

Greenwood

Sussex County · 1 ZIP

52PPM

Single indexed valueNo active flag

Harrington

Kent County · 1 ZIP

54PPM

Single indexed valueNo active flag

Hartly

Kent County · 1 ZIP

55PPM

Single indexed valueNo active flag

Hockessin

New Castle County · 2 ZIPs

81PPM

Single indexed valueNo active flag

Kenton

Kent County · 1 ZIP

56PPM

Single indexed valueNo active flag

Laurel

Sussex County · 1 ZIP

58PPM

Single indexed valueNo active flag

Lewes

Sussex County · 1 ZIP

47PPM

Single indexed valueNo active flag

Lincoln

Sussex County · 1 ZIP

50PPM

Single indexed valueNo active flag

Middletown

New Castle County · 1 ZIP

79PPM

Single indexed valueNo active flag

Milford

Sussex County · 1 ZIP

53PPM

Single indexed valueNo active flag

Millsboro

Sussex County · 1 ZIP

54PPM

Single indexed valueNo active flag

Millville

Sussex County · 2 ZIPs

55PPM

Range 54–55.1No active flag

County comparison

Highest indexed county medians

CountyMedianRangeZIP profiles
New Castle County79 PPM57.3–82.417
Kent County54 PPM51.7–57.211
Sussex County54 PPM47.3–58.620