ZipCheckup grade for 74631: A.
The model grade is high, but the records on this page include findings worth reviewing.
Your top priority: match a filter's certification to the violations (14 health-based violations). Check your ZIP → NSF certified filters
Blackwell, OK (74631): 14 Health-Based Violations Recorded for Mapped Water Systems - 87/100
EPA data combined for 4 water systems mapped to this ZIP (largest mapped system: Blackwell Municipal Authority)
Health-based violation records by water system:
EPA records for the water systems mapped to 74631 in Blackwell, OK contain 23 recorded violations for inclusive record years 2021 through 2026, all mapped systems combined; 14 are marked health-based.
Data source: U.S. Environmental Protection Agency (EPA) SDWIS
At a Glance
- Water EPA records for water systems mapped to this ZIP show 14 health-based violations and 9 non-health-based (since 2021).
- Lead The reported 90th-percentile lead result is below the laboratory reporting limit, not a measured zero; EPA's health goal for lead is zero.
- Radon EPA Zone 3 - county-level radon potential, not evidence of a low home result.
- Flood 159 cumulative NFIP claim records. This historical count is not a current property-risk verdict.
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Score Breakdown
Overall Home Safety Score: 87/100
This is the published model score. Component and domain values are shown independently; they are not added together on this page.
Canonical components
Required domains
Coverage: 4 of 4 components and 3 of 3 domains observed.
Model 4.0.0; series home-safety-v4-cross-vertical.
Safety & Health (7) CRITICAL
Your Water System
ZIP code 74631 in Blackwell, Oklahoma is mapped to the water system Blackwell Municipal Authority (EPA ID: OK1021101). This system provides water to approximately 7,668 people from surface water sources.
There are 4 community water systems serving this area.
Water Systems Serving This Area
| System Name | EPA ID | Population | Source |
|---|---|---|---|
| Blackwell Municipal Authority | OK1021101 | 7,668 | Surface water |
| Kay County Rural Water District 7 | OK3003601 | 920 | Surface water |
| Tonkawa | OK2003603 | 3,299 | Groundwater |
| Garfield Company Rwd #6 | OK2002415 | 1,225 | Groundwater |
Other Water Quality Reports in Oklahoma
- 73001 (Albert)
- 73002 (Alex) - 39 violations recorded for mapped water systems
- 73003 (Edmond)
- 73004 (Amber) - 166 violations recorded for mapped water systems
- 73005 (Anadarko) - 102 violations recorded for mapped water systems
- 73006 (Apache) - 39 violations recorded for mapped water systems
- 73007 (Arcadia) - 30 violations recorded for mapped water systems
- 73008 (Bethany) - 7 violations recorded for mapped water systems
- 73009 (Binger) - 14 violations recorded for mapped water systems
- 73010 (Blanchard) - 677 violations recorded for mapped water systems
- 73011 (Bradley) - 105 violations recorded for mapped water systems
- 73012 (Edmond) - 8 violations recorded for mapped water systems
- 73013 (Edmond) - 8 violations recorded for mapped water systems
- 73014 (Calumet) - 90 violations recorded for mapped water systems
- 73015 (Carnegie) - 6 violations recorded for mapped water systems
- 73016 (Cashion) - 195 violations recorded for mapped water systems
- 73017 (Cement) - 109 violations recorded for mapped water systems
- 73018 (Chickasha) - 191 violations recorded for mapped water systems
- 73019 (Norman) - 3 violations recorded for mapped water systems
- 73020 (Choctaw) - 290 violations recorded for mapped water systems
Nearby Water Quality Reports
- 74646 (Nardin) - 8 mi - 23 violations recorded for mapped water systems
- 74653 (Tonkawa) - 8 mi - 10 violations recorded for mapped water systems
- 74632 (Braman) - 9 mi - 3 violations recorded for mapped water systems
- 74602 (Ponca City) - 11 mi
- 74636 (Deer Creek) - 13 mi
- 74647 (Newkirk) - 13 mi - 146 violations recorded for mapped water systems
- 74601 (Ponca City) - 13 mi - 30 violations recorded for mapped water systems
- 74604 (Ponca City) - 14 mi - 210 violations recorded for mapped water systems
- 74643 (Lamont) - 17 mi - 7 violations recorded for mapped water systems
- 74644 (Marland) - 18 mi - 14 violations recorded for mapped water systems
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View available EPA compliance records for Blackwell Municipal Authority (OK1021101) on EPA.gov.
5 of the top compounds applied across the surrounding county in USGS pesticide-use estimates appear on EPA drinking-water monitoring lists. See the agricultural pesticide-use section.
Compliance History
UCMR 5 PFAS monitoring: no reportable detections in available records
Available federal UCMR5 records for water systems mapped to ZIP code 74631 show no PFAS detections among the compounds tested, at the program's reporting levels.
The EPA Fifth Unregulated Contaminant Monitoring Rule (UCMR5) required community and non-transient non-community water systems serving 3,300 or more people to test for 29 PFAS compounds and lithium between 2023 and 2025. Systems with no detections at the federal minimum reporting level had no results at or above that reporting level.
Health Risks from Detected Contaminants
Total Trihalomethanes (TTHM)
High RiskEPA reference value: 0.08 mg/L · 7 violations on record
Long-term exposure is associated with increased cancer risk, including bladder cancer; possible reproductive effects
At-risk groups: pregnant women, long-term consumers of chlorinated water
Treatment options (verify a product is certified to reduce this contaminant): granular activated carbon (GAC), carbon block filter, point-of-entry aeration · Find a filter →
Environmental Hazards (11) HIGH
Home & Infrastructure (6) HIGH
Possible home maintenance concerns - talk to a local expert.
Call (855) 384-4856Paid Partner This is a free service. You will be connected with an independent service provider. We may receive compensation.
Cost & Community (9) HIGH
CPSC product recall notices
These national notices are not matched to this ZIP code or water system.
Protect Your Home in Blackwell
Based on local data for ZIP 74631, these services may benefit homeowners in your area.
Based on local data for your area. Use the tools below to explore your options.
Home & Flood Insurance
The ZIP code for this report in Blackwell has 159 FEMA flood claims on record. Standard homeowner policies don't cover flood damage - make sure you're protected.
Typical cost: Flood insurance: premiums vary by property and flood zone; request a quote
Check Your Flood Zone (Free)FEMA flood map lookup - see if your property is in a flood zone
Free tip: Check your FEMA flood zone at msc.fema.gov (free lookup)
Gutter Installation & Repair
The median home in 74631 was built around 1955. Aging gutters can cause foundation damage, basement flooding, and mold - a professional assessment can prevent costly repairs.
Typical cost: Gutter installation: typically $1,000–$2,500 for a standard home
Estimate Your Home Maintenance CostsWindow Replacement
The median build year of homes in Blackwell is 1955; check the age and condition of your own windows. ENERGY STAR windows can save $101–$583/year on energy bills.
Typical cost: Window replacement: typically $300–$800 per window installed
Estimate Your Home Maintenance CostsRoofing Inspection & Repair
Homes built around 1955 may be on their second or third roof. A professional inspection can catch damage before leaks start.
Typical cost: Roof inspection: typically $75–$300; repairs $300–$1,500
Estimate Your Home Insurance NeedsService recommendations are based on public data for this ZIP code (FEMA, Census ACS, NWS). Actual needs vary by property. By calling, your information will be shared with an independent service provider. ZipCheckup may receive compensation. Cost estimates are approximate and vary by property, condition, and contractor.
Frequently Asked Questions
Is the tap water in 74631 safe to drink?
EPA SDWIS records 23 violations since 2021 across the water systems mapped to ZIP 74631 (primary system: Blackwell Municipal Authority), including 14 health-based. The violation table above shows which system each record belongs to. ZipCheckup last updated this page in July 2026. The federal source release date is unavailable, so that month is not presented as source currency.
Where does 74631's water come from?
The recorded water source for Blackwell Municipal Authority, a system mapped to ZIP code 74631, is Surface water. This system serves approximately 7,668 people.
How does Blackwell water compare to the national average?
Blackwell's Home Safety Score ranks better than 80% of U.S. ZIP codes, and lower than 53% of ZIP codes within Oklahoma.
How can I get my water tested in Blackwell?
If Blackwell Municipal Authority supplies your home, contact it for its Consumer Confidence Report; otherwise contact the water utility that serves your address, or hire a certified lab for independent home water testing. The EPA recommends annual testing if you use a private well.
What is the radon risk for 74631?
74631 is mapped to a county in EPA Radon Zone 3 (low county-level radon potential; EPA recommends testing every home), located in Kay County. EPA radon zones range from Zone 1 (highest county-level potential) to Zone 3 (lowest). Testing your home is recommended regardless of zone.
What does the NFIP claim history show for ZIP 74631?
FEMA records contain 159 flood insurance claims filed in ZIP code 74631; the recorded rated-zone value (the most frequent one if there are several claims) is A10, which is claims evidence and may differ from the current FEMA map zone for a property. This is a substantial claim history, but claim count is not a count of distinct events or properties. Review FEMA's map for the specific property.
How to cite this page
ZipCheckup. (2026). Blackwell, OK (74631): 14 Health-Based Violations Recorded for Mapped Water Systems - 87/100. https://zipcheckup.com/report/74631/
@misc{zipcheckup-report-74631,
author = {{ZipCheckup}},
title = {{Blackwell, OK (74631): 14 Health-Based Violations Recorded for Mapped Water Systems - 87/100}},
year = {2026},
url = {https://zipcheckup.com/report/74631/}
}
Page version: October 2026.
Nearby ZIP Code Reports
Water quality comparison for ZIP codes near 74631
| ZIP Code | City, State | Distance | Grade | Violations |
|---|---|---|---|---|
| 74646 | Nardin, OK | 8.1 mi | N/A | 23 |
| 74653 | Tonkawa, OK | 8.4 mi | N/A | 10 |
| 74632 | Braman, OK | 9.2 mi | N/A | 3 |
| 74602 | Ponca City, OK | 11.0 mi | N/A | 0 |
| 74636 | Deer Creek, OK | 12.6 mi | N/A | 0 |
| 74647 | Newkirk, OK | 13.0 mi | N/A | 146 |
| 74601 | Ponca City, OK | 13.4 mi | C | 30 |
| 74604 | Ponca City, OK | 14.2 mi | C | 210 |
| 74643 | Lamont, OK | 16.8 mi | N/A | 7 |
| 74644 | Marland, OK | 18.2 mi | N/A | 14 |
Nearby ZIP Code Reports
2026 Rankings for Your Area
Overall safety breakdown
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ZIP 74631 scores in the top tier nationally.