Hardness
Very Hard
358.5 PPM · 21 GPG
Local water dashboard
Official source aggregationWater quality in Manhattan, KS 66502
A source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for Riley County.
1 reported benchmark flag
- Primary matched system
- Manhattan, City Of
- Source water
- Groundwater
- County
- Riley County
- Profile updated
At a glance
What the current records say
EPA quarter 2026Q2
Compliance screen
No active flag
0 active health-based records
Lead 90th percentile
0.0019 mg/L
13% of action level
Utility match
10 systems
Serves 54,763 people system-wide
Hardness meter
How hard is the water?
Estimated local hardness
USGS hardness classification scale
358.5 PPM
Soft
0–59Moderate
60–120Hard
121–180Very hard
181+
0–59Moderate
60–120Hard
121–180Very hard
181+
Parts per million
358.5
mg/L as CaCO₃ equivalent
Grains per gallon
21
1 GPG ≈ 17.1 PPM
What this means at home
At 358.5 PPM, mineral scale can build up on fixtures and heating elements, reduce soap lather, and leave visible spotting. Hardness is primarily an aesthetic and appliance concern—not itself a tap-water safety rating.
USGS sites used
6
Nearest site
13.3 mi
Observation range
Jul 23, 2018–Jul 31, 2024
Estimate confidence
Moderate
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: 10S 10E 03CCBC01 (Well).USGS source documentation ↗
Regional context
Is 66502 typical?
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Manhattan median
359 PPM
About the same3 indexed ZIP readings · Range 358.5–383 PPM
Kansas median
289 PPM
70 PPM higher540 indexed ZIP readings · Range 72.2–707 PPM
EPA benchmark screen
Contaminant snapshot
Available numerical results from associated SDWIS community water systems, compared with the applicable action level or federal MCL. Federal measured-value coverage is incomplete.
1 pass1 fail
Lead (PB90)
0.0019 mg/L
Reported Dec 31, 2023
Copper (CU90)
2.357 mg/L
Reported Dec 31, 1993
Numerical coverage
2 comparable results
Missing values remain blank; absence is not treated as a pass.
Lead (90th percentile)
Measured in mg/L
Local 0.0019
EPA limit 0.015
Copper (90th percentile)
Measured in mg/L
Local 2.357
EPA limit 1.3
Share of EPA benchmark
100% line = listed limit
2026Q2
- All records
- 29
- Health-based
- 1
- Active health-based
- 0
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Revised Total Coliform Rule | KS2016134 | Archived | Nov 1, 2025through Nov 30, 2025 |
| Chlorine | KS2016134 | Archived | Nov 1, 2025through Nov 30, 2025 |
| Revised Total Coliform Rule | KS2016102 | Archived | Sep 1, 2025through Sep 30, 2025 |
| Chlorine | KS2016102 | Archived | Sep 1, 2025through Sep 30, 2025 |
| Revised Total Coliform Rule | KS2016118 | Archived | Jul 1, 2025through Jul 31, 2025 |
| Chlorine | KS2016118 | Archived | Jul 1, 2025through Jul 31, 2025 |
| Chlorine | KS2016119 | Archived | Jul 1, 2025through Jul 31, 2025 |
| Revised Total Coliform Rule | KS2016119 | Archived | Jul 1, 2025through Jul 31, 2025 |
| Chlorine | KS2016102 | Resolved | Jan 1, 2025through Jan 31, 2025 |
| Total Haloacetic Acids (HAA5) | KS2016102 | Archived | Jan 1, 2025through Dec 31, 2025 |
| TTHM | KS2016102 | Archived | Jan 1, 2025through Dec 31, 2025 |
| Revised Total Coliform Rule | KS2016102 | Resolved | Jan 1, 2025through Jan 31, 2025 |
| Chlorine | KS2016102 | Resolved | Sep 1, 2024through Sep 30, 2024 |
| Revised Total Coliform Rule | KS2016102 | Resolved | Sep 1, 2024through Sep 30, 2024 |
| Lead and Copper Rule | KS2014923 | Resolved | Nov 1, 2023through Feb 21, 2024 |
| Public Notice | KS2016102 | Resolved | Aug 4, 2022through Jul 30, 2022 |
| Revised Total Coliform RuleHealth-based | KS2016102 | Resolved | Jun 1, 2022through Jun 30, 2022 |
| Revised Total Coliform Rule | KS2016109 | Resolved | Feb 1, 2022through Feb 28, 2022 |
| Revised Total Coliform Rule | KS2016134 | Resolved | Feb 1, 2022through Feb 28, 2022 |
| Chlorine | KS2016109 | Resolved | Jan 1, 2022through Mar 8, 2022 |
No reported violation does not prove that every contaminant was tested or absent; SDWIS measured values are incomplete and lag state records.
Solutions matcher
Your personalized water action plan
Matched to Manhattan ZIP 66502 using 358.5 PPM nearby hardness and 2 reported measurement benchmarks.
Scale protection
High-Capacity Whole House Water Softener
358.5 PPM is 3× the high-hardness trigger used by this matcher.
Designed to reduce scale on fixtures, water heaters, glassware, and plumbing throughout the home.
Compare whole-house systemsDrinking water protection
Under-Sink Reverse Osmosis System
Copper (90th percentile) has a measured benchmark flag or active health-based SDWIS record in this profile.
A certified multi-stage RO system targets a broader range of dissolved contaminants at the kitchen tap.
Explore under-sink filtrationAffiliate disclosure: we may earn a commission from qualifying purchases, at no added cost to you. Product matching is educational and does not replace certified water testing.
Nearby indexed reports
Compare ZIPs in Manhattan
Estimates can differ across a city because monitoring locations and associated systems differ.
Frequently asked
Water questions for Manhattan
Is tap water safe in Manhattan?+
EPA ECHO shows no active health-based violation for the associated systems in this reporting snapshot. This does not prove every contaminant is absent; federal records can lag and household plumbing can change tap conditions.
How hard is the water?+
Nearby USGS observations produce an estimate of 358.5 PPM, or 21 grains per gallon, classified as very hard. This is not a household tap measurement.
Do I need a water softener?+
At 358.5 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.