Tap Water Quality Report
Tap water quality in OLATHE, Kansas
Tap water in OLATHE, Kansas receives a grade of C (78/100) from TapWaterSafety.org. It's served by OLATHE, CITY OF. The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline; Arsenic detected. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in OLATHE's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving OLATHE.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 25.4 ppb, 423x above the EWG health guideline of 0.06 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 42.8 ppb, 286x above the EWG health guideline of 0.15 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 14.4 ppb, 144x above the EWG health guideline of 0.1 ppb.
Arsenic detected
Moderate concernArsenic detected at 0.333 ppb.
EPA compliance record
Official U.S. EPA records for OLATHE, CITY OF (system ID KS2009115) for the last 3 years. Checked 2026-10-07.
| Rule | Type | Since | Status |
|---|---|---|---|
| Stage 1 Disinfectants and Disinfection Byproducts Rule | Missed testing or reporting | 03/01/2025 | Open |
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Recommended filters for OLATHE
Filters matched to the specific contaminants in OLATHE's water supply.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts. Look for NSF/ANSI 53 VOC reduction.
Reverse osmosis certified for arsenic (NSF/ANSI 58)
$429-$599Reverse osmosis certified under NSF/ANSI 58 for arsenic is the most reliable home option.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
All contaminants detected in OLATHE's tap water
Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Haloacetic acids (HAA9) Disinfection byproduct |
25.4 ppb | 0.06 | — | — | — | — | — | 423× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
42.8 ppb | 0.15 | 80.0 | 100 | — | — | — | 286× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
14.4 ppb | 0.1 | 60.0 | 60 | — | — | — | 144× over |
| Arsenic Heavy metal |
0.333 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 83× over |
| Chromium (hexavalent) Heavy metal |
1.25 ppb | 0.02 | — | — | — | — | — | 62× over |
| Chlorite Disinfection byproduct |
130.0 ppb | 50.0 | 1000.0 | — | — | — | — | 2.6× over |
| Nitrate Inorganic |
0.234 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 1.7× over |
| Bromochloromethane Other |
0.0225 ppb | 0.06 | — | — | — | — | — | Below guideline |
| Chlorate Disinfection byproduct |
68.8 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
2.79 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
77.0 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Molybdenum Other |
4.35 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Selenium Heavy metal |
2.1 ppb | 30.0 | 50.0 | 20 | 40 | 30 | — | Below guideline |
| Manganese Heavy metal |
1.14 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Strontium Radiological |
0.363 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Chromium (total) Heavy metal |
2.03 ppb | — | 100.0 | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.737 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Lithium Other |
19.2 ppb | — | — | — | — | — | — | Below guideline |
| Metolachlor Pesticide/Herbicide |
0.403 ppb | — | — | — | — | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines, California OEHHA PHGs, EWG Tap Water Database.
Treatment plant contact info
For service issues, water quality concerns, or to request a Consumer Confidence Report from OLATHE, CITY OF.