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Local water dashboard

Official source aggregation

Water quality in Rock Valley, IA 51247

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

1 reported benchmark flag
Primary matched system
Rock Valley Water Supply
Source water
Groundwater
County
Sioux County
Profile updated

At a glance

What the current records say

Hardness

Very Hard

465 PPM · 27.2 GPG

Compliance screen

No active flag

0 active health-based records

Lead 90th percentile

0.002 mg/L

13% of action level

Utility match

2 systems

Serves 4,059 people system-wide

Hardness meter

How hard is the water?

Very Hard

Estimated local hardness

USGS hardness classification scale

465 PPM

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

Parts per million

465

mg/L as CaCO₃ equivalent

Grains per gallon

27.2

1 GPG ≈ 17.1 PPM

What this means at home

At 465 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

23

Nearest site

53.6 mi

Observation range

Aug 9, 2016–Apr 21, 2026

Estimate confidence

Low

Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: 29N 7E 35DC (D-J3) (Well).USGS source documentation ↗

Regional context

Is 51247 typical?

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

Rock Valley median

465 PPM

About the same

1 indexed ZIP readings · Range 465–465 PPM

Iowa median

281 PPM

184 PPM higher

721 indexed ZIP readings · Range 182–834 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)

0.002 mg/L

Reported Dec 31, 2025

Copper (CU90)

1.7 mg/L

Reported Dec 31, 1998

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 0.002

EPA limit 0.015

Local level is 13% of the listed EPA limit.

Copper (90th percentile)

Measured in mg/L

Fail

Local 1.7

EPA limit 1.3

Local level is 131% 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
2
Health-based
0
Active health-based
0
Contaminant or ruleSystemStatusPeriod
TTHMIA8482096ResolvedAug 1, 2024through Aug 31, 2024
Total Haloacetic Acids (HAA5)IA8482096ResolvedAug 1, 2024through Aug 31, 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 Rock Valley ZIP 51247 using 465 PPM nearby hardness and 2 reported measurement benchmarks.

2 matches

Scale protection

High-Capacity Whole House Water Softener

465 PPM is 4× 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

Copper (90th percentile) 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 Rock Valley

Is tap water safe in Rock Valley?+

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 465 PPM, or 27.2 grains per gallon, classified as very hard. This is not a household tap measurement.

Do I need a water softener?+

At 465 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.