Is Flandreau, SD 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 ↓
63.9/100
waterverge.com Flandreau, SD — Water Quality Report
Flandreau's drinking water received a grade of C (63.9 out of 100), indicating fair water quality. The city's 3 water systems serve approximately 2,854 residents using purchased ground water.
Lead levels were measured at 7.7 ppb (90th percentile), which is within EPA limits but above recommended levels. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 147 violations on record, including 19 health-based violations. 12 remain unresolved.
What to know about Flandreau's water
Flandreau ranks #124 out of 141 cities in South Dakota for water quality, placing it among the lowest-rated in the state.
Flandreau purchases its water from a regional wholesaler, meaning quality depends on both the supplier's treatment and the local distribution system's condition.
While lead levels are within EPA limits, they are above the recommended 5 ppb threshold that health organizations consider ideal. A point-of-use filter adds an extra layer of protection.
As a small community water system, Flandreau may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 11 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Flandreau, SD water safe to drink?
Flandreau's drinking water has significant quality concerns based on EPA testing data. With a grade of C (63.9/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 2,854 residents using groundwater (wells).
Recent water quality updates for Flandreau
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Flandreau's water quality assessment. Grade: C (63.9/100).
Contaminants: Lead and Copper Rule.
Contaminants: Total Haloacetic Acids (HAA5), TTHM.
Contaminants: Lead and Copper Rule.
Federal disaster declaration (FEMA DR-4807). Flood event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-4440). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Flandreau's water supply.
Within EPA limits but above the American Academy of Pediatrics recommended level of 1 ppb. An NSF 53-certified filter provides additional protection.
Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.
Violation history
Flandreau's water system has 147 total violations on record, including 19 health-based violations. 12 remain unresolved. 11 violations were issued in the last 5 years.
Flood & environmental risk
Moody County has experienced 10 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. Local water sources include Spring Creek, Flandreau Creek Above Flandreau.
Where does Flandreau's water come from?
Flandreau's drinking water comes from groundwater (wells), supplied by 3 water systems serving approximately 2,854 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Spring Creek (river), Flandreau Creek Above Flandreau (river).
What Flandreau residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Flandreau'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.
Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.
Flandreau'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
Drought conditions
D2 — severe droughtMoody County is currently in D2 (severe 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.
Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.
Flood & disaster history
Moody County has experienced 10 federally declared disasters since 1969. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Flandreau's water supply, we recommend the following filter types.
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. | 7.7 | 15 | ppb | Inorganic | Safe |
| Copper (90th percentile) CopperInorganic A metal that enters drinking water mainly through corrosion of copper plumbing. Small amounts are essential for health, but excess levels are harmful. Health EffectsGastrointestinal distress (nausea, vomiting, diarrhea) at short-term high levels; liver and kidney damage from long-term exposure. EPA Limit1.3 mg/L action level Common SourcesCorrosion of copper household plumbing, erosion of natural deposits. | 3.00 | 1.3 | mg/L | Inorganic | Over Limit |
Lead level trend (90th percentile)
Copper level trend (90th percentile)
See how Flandreau compares by contaminant
Explore where Flandreau ranks among all South Dakota cities for specific contaminants.
Water source & infrastructure
Where Flandreau's water comes from
Flandreau purchases its water supply from a regional wholesale provider rather than treating raw water directly.
Water quality depends on both the wholesaler's treatment standards and the condition of Flandreau's local distribution pipes and storage facilities.
Purchased water systems are common in suburban areas and smaller communities that lack the infrastructure for independent treatment.
The system is operated by local government ownership and serves approximately 2,854 people through 3 water systems.
Water bodies near Flandreau
Flandreau is located near 2 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Flandreau
| System Name | PWSID | Population | Source |
|---|---|---|---|
| FLANDREAU | SD4600127 | 2,372 | GWP |
| FLANDREAU SCHOOL | 084690465 | 375 | GWP |
| PLEASANT VALLEY COLONY | SD4602086 | 107 | GW |
How Flandreau compares
Full South Dakota rankings →Flandreau's score of 63.9/100 is on par with the average of 66/100 among major South Dakota cities. It outscores 5 of 10 nearby cities.
Nearby cities
View South Dakota rankings →ZIP codes served by Flandreau
The water systems serving Flandreau cover 1 ZIP code. Select any ZIP to see which water systems serve that area.
About Flandreau, SD
Wikipedia →Flandreau FLAN-droo is a city in and county seat of Moody County, South Dakota, United States. The population was 2,372 at the 2020 census. It was named in honor of Charles Eugene Flandrau, a judge in the territory and state of Minnesota. He is credited with saving the community of New Ulm, Minnesota, from destruction during conflict with the Sioux tribe in 1862.
Learn more about your water
Guides and resources related to Flandreau's water quality findings.
Explore water quality across Moody
Frequently asked questions
Is Flandreau, SD tap water safe to drink?
Flandreau's water quality earned a grade of C (63.9/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #124 out of 141 cities tested in South Dakota.
What contaminants are in Flandreau's water?
Lead was measured at 7.7 ppb (90th percentile). 147 violations are on record.
How is Flandreau'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 Flandreau?
While lead levels are within EPA limits, a filter adds extra protection. Based on current data, basic filtration should suffice for additional peace of mind.
Where does Flandreau's water come from?
Flandreau's water is sourced from Purchased ground water. The city has 3 water systems serving approximately 2,854 residents.
What health violations has Flandreau's water system had?
Flandreau has 19 health-based violations on record. The most recent violation was recorded in October 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 12 violations remain unresolved.
Is Flandreau's groundwater at risk of contamination?
Flandreau 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 147 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 Flandreau's water compare to other cities?
Flandreau ranks #124 out of 141 cities in South Dakota (better than 12% of state cities) and #11709 out of 15744 cities nationally (26th percentile). The grade of C reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.