D27/100

ROCK VALLEY WATER SUPPLY — Water Quality Report 2026

Serving 4,059 people · Iowa

Water Source
Groundwater
County
System ID
IA8482096
Violations
18

Contaminant Test Results

2 contaminants above EPA health goals
ContaminantDetectedLimit (MCL)Status
Copper (90th percentile)
1.70 mg/L1.30 mg/LOver Limit
Lead (90th percentile)
0.002 mg/L0.015 mg/LAbove Goal

EPA Violation History

2

Violations (last 5yr)

0

Unresolved

0

Health-Related

TIER 3Resolved

Failed Level 2 Assessment under Revised Total Coliform Rule

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: August 1, 2024 – August 31, 2024Rule: Stage 2 DBPREnforcement: Resolving — corrective action underway
TIER 3Resolved

Failed Level 2 Assessment under Revised Total Coliform Rule

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: August 1, 2024 – August 31, 2024Rule: Stage 2 DBPREnforcement: Resolving — corrective action underway

Understanding violation severity

Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.

Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly

Frequently Asked Questions About ROCK VALLEY WATER SUPPLY

Is ROCK VALLEY WATER SUPPLY water safe to drink?

ROCK VALLEY WATER SUPPLY water receives a grade of D (27/100), which is considered poor. 1 contaminant(s) exceed EPA legal limits and 18 violation(s) are on record. Customers may want to consider using a water filter.

What contaminants has ROCK VALLEY WATER SUPPLY detected?

52 contaminants were tested in ROCK VALLEY WATER SUPPLY's water. Notable contaminants include Copper (90th percentile), Lead (90th percentile). 1 exceed EPA legal limits (MCLs). 2 exceed EPA health goals (MCLGs).

Does ROCK VALLEY WATER SUPPLY have any EPA violations?

Yes, ROCK VALLEY WATER SUPPLY has 18 EPA violation(s) on record, with the most recent in 2024. Violation types include MR, MCL. 11 are health-based violations.

How many people does ROCK VALLEY WATER SUPPLY serve?

ROCK VALLEY WATER SUPPLY serves approximately 4,059 people, Iowa. The system provides water to 1 community: Rock Valley.

What type of water does ROCK VALLEY WATER SUPPLY provide?

ROCK VALLEY WATER SUPPLY sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is IA8482096.

How does ROCK VALLEY WATER SUPPLY compare to other utilities in Iowa?

ROCK VALLEY WATER SUPPLY scores 27/100 with a grade of D (poor). This score suggests significant water quality concerns relative to other utilities. Visit our Iowa state page for a full comparison of water systems.

Cities Served