WaterVerge

Is Sterling, CO Tap Water Safe to Drink?

Graded C- — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

15K residents served 3 water systems PWSID: CO0138045
Overall Score
56.6 / 100
Violations
17 active
Last Updated
May 2026
Source
Ground water under influence
#151 of 246 in Colorado Top 79% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
C-GRADE
Water Quality Grade
56.6/100
waterverge.com
C- 56.6/100

Sterling, CO — Water Quality Report

Sterling's drinking water received a grade of C- (56.6 out of 100), indicating poor water quality. The city's 3 water systems serve approximately 15,323 residents using ground water under influence.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 159 violations on record, including 29 health-based violations. 17 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Sterling's water

Sterling ranks #151 out of 246 cities in Colorado for water quality, placing it below average in the state.

Sterling relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.

PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.

Hexavalent chromium (chromium-6) was detected at 0.12 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration.

The system has seen 31 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
56.6 out of 100 Grade C-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
15/45
F
Historical violation record including health-based and monitoring violations.
Lead & Copper
16/20
B
Lead at 0.0 ppb (90th percentile).
Contaminants
14.1/20
C
1 PFAS compound detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
3.5/5
C
Water source: Ground water under influence.
Water Safety

Is Sterling, CO water safe to drink?

Concerns Identified

Sterling's drinking water has significant quality concerns based on EPA testing data. With a grade of C- (56.6/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 15,323 residents using groundwater (wells).

17
Active Violations
0.0 ppb
Lead (90th %ile)
1 compound
PFAS Detected
8 events
Disaster History

Recent water quality updates for Sterling

A timeline of significant water quality events, violations, and data updates.

PFAS
1 PFAS "forever chemical" compound detected

Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Sterling's water quality assessment. Grade: C- (56.6/100).

Disaster
SEVERE STORMS, FLOODING, AND TORNADOES

Federal disaster declaration (FEMA DR-4731). Flood event — may have impacted local water infrastructure.

Violation
3 drinking water violations recorded

Contaminants: Turbidity, E. COLI, Cryptosporidium.

Violation
1 drinking water violation recorded

Contaminants: Turbidity.

Violation
1 drinking water violation recorded

Contaminants: Cryptosporidium.

Key contaminant findings

Based on the most recent EPA sampling data for Sterling's water supply.

Lead Within Limits
Detected: 0.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Copper Exceeds Limit
Detected: 1.60 mg/L Limit: 1.3 mg/L (EPA Action Level)

Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.

PFAS (1 compound) Elevated
Detected: Highest: lithium at 12.5000 µg/L Limit: 0.004 µg/L (EPA MCL)

Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.

Violation history

Sterling's water system has 159 total violations on record, including 29 health-based violations. 17 remain unresolved. 31 violations were issued in the last 5 years.

MROtherMONMCL
Most recent violations:
Aug 2023 Turbidity Resolved
Aug 2023 E. COLI Resolved
Aug 2023 Cryptosporidium Resolved
Jul 2023 Turbidity Resolved
Jun 2023 Cryptosporidium Resolved

Flood & environmental risk

Logan County has experienced 8 federally declared disasters since 1969. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies.

SEVERE STORMS, FLOODING, AND TORNADOES
Flood FEMA DR-4731
SEVERE STORMS, TORNADOES, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA DR-4229
SEVERE STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA DR-4145

Where does Sterling's water come from?

Sterling's drinking water comes from groundwater (wells), supplied by 3 water systems serving approximately 15,323 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.

What Sterling residents can do

Install a water filter

Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Sterling's water.

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Monitor alerts during storms

Sterling's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
0.0 ppb
EPA Action Level: 15 ppb · 0% of limit
Safe Level
Copper (90th percentile)
Inorganic
Over Limit
1.60 mg/L
EPA Action Level: 1.3 mg/L · +20% over limit
Exceeds Limit
lithium
PFAS / Forever Chemical
Near MCL
12.5000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
5.3 µg/L
EPA MCL: 60 µg/L · 9% of limit
Within LimitUCMR 4 DataHAA6Br: 9.8 µg/LHAA9: 10.4 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
0.12 µg/L
CA MCL (no federal MCL): 10 µg/L · 1% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
270.0 µg/L
EPA Health Ref Level: 1,500 µg/L · 18% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Detected
1.2 µg/L
EPA Secondary MCL: 50 µg/L · 2% of limit
DetectedUCMR 4 Data
Vanadium
Inorganic
Detected
2.20 µg/L
EPA Short-term HA: 21 µg/L · 10% of limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Elevated
180.0 µg/L
EPA Lifetime HA: 210 µg/L · 86% of limit
DetectedUCMR 3 Data
Lithium
Inorganic
Detected
12.5 µg/L
State screening level: 60 µg/L · 21% of limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
1
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

159
Total violations
29
Health-based
17
Active / unresolved
Aug 2023
Most recent violation
Compliance Record

Violations & advisories

159 Total
17 Active
29 Health-based
142 Resolved
Violations by category
Volatile Organic Chemicals
64
Inorganic Chemicals
21
Radionuclides and Revised Rad Rule
17
Stage 1 Disinfectants and Disinfection Byproducts Rule
12
Total Coliform Rule
10
Oct 2022 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2022 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Apr 2021 Active
Public Notice
Other Violation 0
Jan 2021 Active
Public Notice
Other Violation 0
Jul 2020 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2019 Active
Public Notice
Other Violation 0
Mar 2019 Active
Public Notice
Other Violation 0
Sep 2018 Active
Public Notice
Other Violation 0
Jul 2018 Active
Public Notice
Other Violation 0
Jul 2018 Active
Consumer Confidence Rule
Other Violation 0
Dec 2016 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2012 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2011 Active
Consumer Confidence Rule
Other Violation 0
Oct 2008 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2006 Active
Consumer Confidence Rule
Other Violation 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Aug 2023 Resolved
Turbidity
Monitoring & Reporting
Monitoring & Reporting Resolved Aug 2023
Aug 2023 Resolved
E. COLI
Monitoring & Reporting
Monitoring & Reporting Resolved Aug 2023
Aug 2023 Resolved
Cryptosporidium
Monitoring & Reporting
Monitoring & Reporting Resolved Aug 2023
Showing 20 of 159 violations
Industrial pollution

Top industrial polluters within 10 miles of Sterling

Industrial polluters nearby

Reported releases to surface water by facilities near Sterling, ranked by pounds discharged annually.

FacilityTop chemicalTo surface water (lbs/yr)Distance
CARGILL FEED & NUTRITION STERLING
Food · CARGILL INC
STERLING, CO80751
0.6 mi
STERLING ETHANOL LLC
Chemicals · NA
STERLING, CO80751
1.1 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Drought conditions

D3 — extreme drought

Logan County is currently in D3 (extreme drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.

14
Weeks at D2+ (current streak)
24.6%
Months in D2+ (last 30y)
14
Weeks at D2+ (last 5y)

Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.

Environmental Risk

Flood & disaster history

8
Declared disasters
Aug 2023
Most recent
Flood
Most common type

Logan County has experienced 8 federally declared disasters since 1969. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Aug 2023
SEVERE STORMS, FLOODING, AND TORNADOES
Flood FEMA #4731
Jul 2015
SEVERE STORMS, TORNADOES, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA #4229
Sep 2013
SEVERE STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA #4145
Sep 2013
SEVERE STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA #3365
Sep 2005
HURRICANE KATRINA EVACUATION
Coastal Storm FEMA #3224
Aug 1997
SEVERE STORMS, HEAVY RAIN, FLASH FLOODS, FLOODING, MUDSLIDES
Flood FEMA #1186

Recommended water filters

Based on contaminants detected in Sterling's water supply, we recommend the following filter types.

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
1 PFAS compound detected
🔧
For Copper
Reverse Osmosis or KDF Filter
Copper exceeds the EPA action level of 1.3 mg/L

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 15 ppb Inorganic Safe
Copper (90th percentile) 1.60 1.3 mg/L Inorganic Over Limit
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS ND HI µg/L PFAS Not Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium 12.500 HI µg/L PFAS Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA ND HI µg/L PFAS Not Detected
PFBS ND HI µg/L PFAS Not Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 7.3 ppb from 1992 (9.0 ppb) to 2025 (1.7 ppb).

Copper level trend (90th percentile)

EPA action level: 1.3 mg/L
Copper has increased by 0.200 mg/L from 2010 (1.400 mg/L) to 2012 (1.600 mg/L).
Infrastructure

Water source & infrastructure

Primary Source
Ground Water Under Influence
Operator
Local Government
Population Served
15,323
Water Systems
3
Source breakdown
Groundwater
2
Ground Water Under Influence
1
Water Source

Where Sterling's water comes from

Ground Water Under Influence

Sterling's drinking water is drawn from underground aquifers through wells.

Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.

Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.

The system is operated by local government ownership and serves approximately 15,323 people through 3 water systems.

Infrastructure

Water systems serving Sterling

System Name PWSID Population Source
STERLING CITY OF CO0138045 15,100 GU
SAGE POINTE HOA CO0138042 194 GW
SUNNYSLOPE HOMEOWNERS CO0138725 29 GW
Regional Comparison

How Sterling compares

Full Colorado rankings →

Sterling's score of 56.6/100 is above the average of 45/100 among major Colorado cities. It outscores 9 of 10 nearby cities.

Sterling (this city)
56.6
Denver
39.6
Aurora
38.1
Lakewood
36.9
Colorado avg
45
City Profile

About Sterling, CO

Economic Profile
$44,556
Median Income
$184,039
Median Home Value
$838/mo
Median Rent
3.3%
Unemployment
Community
37.7
Median Age
686
People / sq mi
15.5%
College Educated
63.9%
Homeownership
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Frequently asked questions

Is Sterling, CO tap water safe to drink?

Sterling's water quality earned a grade of C- (56.6/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #151 out of 246 cities tested in Colorado.

What contaminants are in Sterling's water?

Lead was measured at 0.0 ppb (90th percentile). 1 PFAS compound was detected. 159 violations are on record.

How is Sterling's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Sterling?

PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does Sterling's water come from?

Sterling's water is sourced from Ground water under influence. The city has 3 water systems serving approximately 15,323 residents.

What health violations has Sterling's water system had?

Sterling has 29 health-based violations on record. The most recent violation was recorded in August 2023. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 17 violations remain unresolved.

Is Sterling's groundwater at risk of contamination?

Sterling uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 159 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.

How does Sterling's water compare to other cities?

Sterling ranks #151 out of 246 cities in Colorado (better than 39% of state cities) and #12433 out of 15744 cities nationally (21th percentile). The grade of C- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.