Community Water System · PWSID ID5420058

Twin Falls City of

Serves 56,121 peopleGroundwaterOwner: Local GovernmentTwin Falls, Idaho
Nothing open right now.

On record since 2010: 24 violations. 14 missed or late tests · 10 notices or reports. Most recent began 2025-01-01.

None of them is a measurement of contaminated water.

For this year's test results, ask the utility for its annual Consumer Confidence Report. Every community system must publish one.

0Over the limit
0Treatment lapse
14Missed or late test
10Notice or report

More violations on record than 88% of active water systems in Idaho. Small systems with no staff chemist often rack up missed-test violations; big utilities rarely do.

The record, year by year

20052010 · Missed or late test: 12010 · Notice or report: 22010 · Notice or report: 220102011 · Notice or report: 12012 · Notice or report: 72012 · Notice or report: 72012 · Notice or report: 72012 · Notice or report: 72012 · Notice or report: 72012 · Notice or report: 72012 · Notice or report: 72014 · Missed or late test: 12015 · Missed or late test: 1201520202022 · Missed or late test: 32022 · Missed or late test: 32022 · Missed or late test: 32023 · Missed or late test: 12024 · Missed or late test: 52024 · Missed or late test: 52024 · Missed or late test: 52024 · Missed or late test: 52024 · Missed or late test: 52025 · Missed or late test: 22025 · Missed or late test: 22025
One square = one violation, by the year it began. Empty columns are years with nothing on EPA's record.
58% missed or late test · 1442% notice or report · 10

Across Idaho, 80% of violations are missed or late tests and 5% are water over a limit.

Lead & copper at the tap

Utilities sample taps in homes most likely to have lead pipes, and report the 90th-percentile result: 9 in 10 homes sampled came in at or below this number. Above the red line (the action level) the utility must act. The action level is not a safe level; EPA's health goal for lead is zero. EPA's file does not date these results, so they are shown highest first.

Lead, 90th percentile 10 results on file · action level 15 ppb

2 ppb
1 ppb
1 ppb
0 ppb
0 ppb
0 ppb
0 ppb
0 ppb
0 ppb
0 ppb

Every violation on record

  1. 2025-01-01pHWater Quality Parameter M/RPeriod ended · no return to compliance on file
  2. 2025-01-01Temperature (Centigrade)Water Quality Parameter M/RPeriod ended · no return to compliance on file
  3. 2024-01-01Temperature (Centigrade)Water Quality Parameter M/RPeriod ended · no return to compliance on file
  4. 2024-01-01Alkalinity, TotalWater Quality Parameter M/RPeriod ended · no return to compliance on file
  5. 2024-01-01pHWater Quality Parameter M/RPeriod ended · no return to compliance on file
  6. 2024-01-01Conductivity @ 25 C Umhos/CmWater Quality Parameter M/RPeriod ended · no return to compliance on file
  7. 2024-01-01CalciumWater Quality Parameter M/RPeriod ended · no return to compliance on file
  8. 2023-01-01NitrateMonitoring, RegularPeriod ended · no return to compliance on file
  9. 2022-07-01Lead and Copper Rule ×2Initial, Follow-up, or Routine Source Water M/RBack in compliance
  10. 2022-01-01NitrateMonitoring, RegularPeriod ended · no return to compliance on file
  11. 2015-02-17E. ColiMonitoring, Source Water (GWR)Back in compliance
  12. 2014-01-01NitriteMonitoring, RegularPeriod ended · no return to compliance on file
  13. 2012-07-12Public NoticePN Violation for NPDWR ViolationBack in compliance
  14. 2012-05-05Public Notice ×2PN Violation for NPDWR ViolationBack in compliance
  15. 2012-03-03Public Notice ×2PN Violation for NPDWR ViolationBack in compliance
  16. 2012-01-02Public Notice ×2PN Violation for NPDWR ViolationBack in compliance
  17. 2011-04-05Public NoticePN Violation for NPDWR ViolationBack in compliance
  18. 2010-12-31Public NoticePN Violation for NPDWR ViolationBack in compliance
  19. 2010-11-01Public NoticePN Violation for NPDWR ViolationBack in compliance
  20. 2010-08-10E. ColiMonitoring, Source Water (GWR)Back in compliance

System details

Population served56,121
Service connections19,273
Water sourceGroundwater
System typeCommunity Water System
OwnerLocal Government
StatusActive
CityTwin Falls
EPA ZIP on file83301

Areas served

  • Twin Falls County

Reading this record

Twin Falls City of is a community water system that draws from groundwater and serves about 56,121 people in Twin Falls, Idaho. Everything above comes from the EPA's Safe Drinking Water Information System (SDWIS), where states report every violation by every public water system.

Four kinds of violation. Only one is a measurement of the water: over the limit means a test came back above a legal maximum (an MCL). A treatment lapse means a required protective step was not done, such as disinfection, filtration, fixing a defect an inspector found, or filing a lead-pipe inventory. A missed or late test means a required test was skipped or never reported. That is the most common kind, and the most misread: it does not mean the water was bad, and it does not mean the water was fine. Notices and reports covers public notices and the annual Consumer Confidence Report.

Status. “Back in compliance” means the state recorded a return to compliance. “Period ended” means the violation's compliance period is over but no return to compliance was ever filed, which is common in older records. EPA's federal copy lags state records by months, so call the utility for anything current.