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Local water dashboard

Official source aggregation

Water quality in Delafield, WI 53018

A source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for Waukesha County.

1 reported benchmark flag
Primary matched system
Delafield Square
Source water
Groundwater
County
Waukesha County
Profile updated

At a glance

What the current records say

Hardness

Very Hard

417 PPM · 24.4 GPG

Compliance screen

No active flag

0 active health-based records

Lead 90th percentile

0.0012 mg/L

8% of action level

Utility match

10 systems

Serves 587 people system-wide

Hardness meter

How hard is the water?

Very Hard

Estimated local hardness

USGS hardness classification scale

417 PPM

Soft
0–59
Moderate
60–120
Hard
121–180
Very hard
181+

Parts per million

417

mg/L as CaCO₃ equivalent

Grains per gallon

24.4

1 GPG ≈ 17.1 PPM

What this means at home

At 417 PPM, mineral scale can build up on fixtures and heating elements, reduce soap lather, and leave visible spotting. Hardness is primarily an aesthetic and appliance concern—not itself a tap-water safety rating.

USGS sites used

69

Nearest site

5.7 mi

Observation range

May 31, 2017–Aug 8, 2024

Estimate confidence

Moderate

Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: 7N19E-29.5f (Well).USGS source documentation ↗

Regional context

Is 53018 typical?

These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.

Delafield median

417 PPM

About the same

1 indexed ZIP readings · Range 417–417 PPM

Wisconsin median

288 PPM

129 PPM higher

556 indexed ZIP readings · Range 41.3–467 PPM

EPA benchmark screen

Contaminant snapshot

Available numerical results from associated SDWIS community water systems, compared with the applicable action level or federal MCL. Federal measured-value coverage is incomplete.

1 pass1 fail

Lead (PB90)

0.0012 mg/L

Reported Sep 30, 2025

Copper (CU90)

Not available

No numerical 90th-percentile result

Numerical coverage

2 comparable results

Missing values remain blank; absence is not treated as a pass.

Lead (90th percentile)

Measured in mg/L

Pass

Local 0.0012

EPA limit 0.015

Local level is 8% of the listed EPA limit.

Di(2-ethylhexyl) phthalate

Measured in UG/L

Fail

Local 10.95

EPA limit 0.006

Local level is 182500% of the listed EPA limit.

Share of EPA benchmark

100% line = listed limit

EPA SDWIS compliance

Reported violation history

Open EPA source documentation ↗
2026Q2
All records
44
Health-based
7
Active health-based
0
Contaminant or ruleSystemStatusPeriod
Revised Total Coliform RuleWI2686359ResolvedApr 1, 2025through Apr 30, 2025
Lead and Copper RuleWI2682512ResolvedJan 1, 2025through Jan 2, 2025
Lead and Copper RuleWI2686359ResolvedJan 1, 2025through Jan 9, 2025
Public NoticeWI2680761UnaddressedOct 17, 2024
Public NoticeWI2680761UnaddressedOct 17, 2024
LEAD AND COPPER RULE REVISIONSWI2680761ResolvedOct 17, 2024through Mar 6, 2025
LEAD AND COPPER RULE REVISIONSHealth-basedWI2680761ResolvedOct 17, 2024through Mar 6, 2025
LEAD AND COPPER RULE REVISIONSWI2682795ResolvedOct 17, 2024through Dec 9, 2024
Public NoticeWI2682795UnaddressedOct 17, 2024
Public NoticeWI2682795UnaddressedOct 17, 2024
LEAD AND COPPER RULE REVISIONSHealth-basedWI2682795ResolvedOct 17, 2024through Dec 9, 2024
LEAD AND COPPER RULE REVISIONSWI2682229ResolvedOct 17, 2024through Oct 29, 2024
Public NoticeWI2682229UnaddressedOct 17, 2024
LEAD AND COPPER RULE REVISIONSWI2682761ResolvedOct 17, 2024through Oct 24, 2024
LEAD AND COPPER RULE REVISIONSHealth-basedWI2682761ResolvedOct 17, 2024through Oct 24, 2024
Public NoticeWI2682761UnaddressedOct 17, 2024
Public NoticeWI2682761UnaddressedOct 17, 2024
LEAD AND COPPER RULE REVISIONSHealth-basedWI2686325ResolvedOct 17, 2024through Jun 6, 2025
Public NoticeWI2686325UnaddressedOct 17, 2024
Public NoticeWI2686325UnaddressedOct 17, 2024

No reported violation does not prove that every contaminant was tested or absent; SDWIS measured values are incomplete and lag state records.

Solutions matcher

Your personalized water action plan

Matched to Delafield ZIP 53018 using 417 PPM nearby hardness and 2 reported measurement benchmarks.

2 matches

Scale protection

High-Capacity Whole House Water Softener

417 PPM is 3× the high-hardness trigger used by this matcher.

Designed to reduce scale on fixtures, water heaters, glassware, and plumbing throughout the home.

Compare whole-house systems

Drinking water protection

Under-Sink Reverse Osmosis System

Di(2-ethylhexyl) phthalate has a measured benchmark flag or active health-based SDWIS record in this profile.

A certified multi-stage RO system targets a broader range of dissolved contaminants at the kitchen tap.

Explore under-sink filtration

Affiliate disclosure: we may earn a commission from qualifying purchases, at no added cost to you. Product matching is educational and does not replace certified water testing.

Frequently asked

Water questions for Delafield

Is tap water safe in Delafield?+

EPA ECHO shows no active health-based violation for the associated systems in this reporting snapshot. This does not prove every contaminant is absent; federal records can lag and household plumbing can change tap conditions.

How hard is the water?+

Nearby USGS observations produce an estimate of 417 PPM, or 24.4 grains per gallon, classified as very hard. This is not a household tap measurement.

Do I need a water softener?+

At 417 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.