SIOUX RURAL WATER SYSTEM

WATERTOWN, SD · ~4,280 people served

Check your exact address → WATERTOWN overview

100

Excellent

PurityRadar safety score

PWSID

SD4600866

State

South Dakota

City

WATERTOWN

Population served

4,280

Primary source

Groundwater

Score history

No change since tracking began Jun 18, 2026.

Jun 18, 2026 · score 100 Jun 18, 2026 · score 100

2 score updates logged since tracking began Jun 18, 2026. Each future EPA re-score adds a point.

PFAS & contaminant readings

Latest detections from EPA’s UCMR5 monitoring (through Dec 2023). Levels in parts per trillion (ppt).

Lithium

30,300 ppt

limit —

No federal limit

Violations & enforcement

Violations on record

Unaddressed

Health-based

Enforcement actions

From EPA ECHO (SDWIS), most recent enforcement Mar 2023. Official EPA record →

Monitoring & reporting · Gross alpha began Jan 2022 Resolved

Monitoring & reporting · Uranium began Jan 2022 Resolved

Monitoring & reporting · Combined radium-226/228 began Jan 2022 Resolved

Max contaminant level (MCL) · Total trihalomethanes (TTHM) health-based began Apr 2020 Resolved

Recent enforcement actions

State action · SOX Mar 2023
State action · SOX Mar 2023
State action · SOX Mar 2023
State action · SIE Jan 2023
State action · SIE Jan 2023
State action · SIE Jan 2023
State action · SOX Jun 2021
State action · SIF Jul 2020

This profile is built from EPA public records for system SD4600866 — SDWIS violations and UCMR5 PFAS sampling. The score is system-level and can’t account for your home’s plumbing (older pipes can add lead at the tap). For health decisions, check your exact address, read the utility’s Consumer Confidence Report, and confirm with your provider.