Is Bison, SD Tap Water Safe to Drink?
Graded A-, with 5 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
85.7/100
waterverge.com Bison, SD — Water Quality Report
Bison's drinking water received a grade of A- (85.7 out of 100), indicating good water quality. The city's 2 water systems serve approximately 780 residents using purchased surface water.
Lead levels were measured at 1.0 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 48 violations on record, including 6 health-based violations. 5 remain unresolved.
What to know about Bison's water
Bison ranks #74 out of 141 cities in South Dakota for water quality, placing it below average in the state.
The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection.
As a small community water system, Bison may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Bison, SD water safe to drink?
Bison's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (85.7/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 780 residents using surface water (rivers, lakes, or reservoirs).
Recent water quality updates for Bison
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Bison's water quality assessment. Grade: A- (85.7/100).
Contaminants: Total Haloacetic Acids (HAA5), TTHM.
Contaminants: Revised Total Coliform Rule.
Federal disaster declaration (FEMA DR-4440). Flood event — may have impacted local water infrastructure.
Contaminants: Revised Total Coliform Rule.
Federal disaster declaration (FEMA DR-4186). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Bison's water supply.
Well within EPA limits.
Violation history
Bison's water system has 48 total violations on record, including 6 health-based violations. 5 remain unresolved. 3 violations were issued in the last 5 years.
Flood & environmental risk
Perkins County has experienced 5 federally declared disasters since 1997. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies.
Where does Bison's water come from?
Bison's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 2 water systems serving approximately 780 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment.
What Bison residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Bison's water.
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.
Bison'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.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Flood & disaster history
Perkins County has experienced 5 federally declared disasters since 1997. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 1.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Bison compares by contaminant
Explore where Bison ranks among all South Dakota cities for specific contaminants.
Water source & infrastructure
Where Bison's water comes from
Bison's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards.
These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge.
The system is operated by private ownership and serves approximately 780 people through 2 water systems.
Water systems serving Bison
| System Name | PWSID | Population | Source |
|---|---|---|---|
| PERKINS COUNTY RURAL WATER | SD4602228 | 470 | SWP |
| BISON | SD4600039 | 310 | SWP |
How Bison compares
Full South Dakota rankings →Bison's score of 85.7/100 is above the average of 66/100 among major South Dakota cities. It outscores 6 of 10 nearby cities.
Nearby cities
View South Dakota rankings →About Bison, SD
Wikipedia →Bison is a town in and the county seat of Perkins County, South Dakota, United States. The population was 302 at the 2020 census.
Learn more about your water
Guides and resources related to Bison's water quality findings.
Explore water quality across Perkins
Frequently asked questions
Is Bison, SD tap water safe to drink?
Bison's water quality earned a grade of A- (85.7/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #74 out of 141 cities tested in South Dakota.
What contaminants are in Bison's water?
Lead was measured at 1.0 ppb (90th percentile). 48 violations are on record.
How is Bison'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 Bison?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Bison's water come from?
Bison's water is sourced from Purchased surface water. The city has 2 water systems serving approximately 780 residents.
What health violations has Bison's water system had?
Bison has 6 health-based violations on record. The most recent violation was recorded in August 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 5 violations remain unresolved.
How does Bison's water compare to other cities?
Bison ranks #74 out of 141 cities in South Dakota (better than 48% of state cities) and #5192 out of 15744 cities nationally (67th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.