Is Olla, LA 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 ↓
58.1/100
waterverge.com Olla, LA — Water Quality Report
Olla's drinking water received a grade of C- (58.1 out of 100), indicating poor water quality. The city's 2 water systems serve approximately 3,105 residents using groundwater.
Lead levels were measured at 0.0 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 31 health-based violations. 12 remain unresolved.
What to know about Olla's water
Olla ranks #182 out of 309 cities in Louisiana for water quality, placing it below average in the state.
Olla relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.
As a small community water system, Olla may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Olla, LA water safe to drink?
Olla's drinking water has significant quality concerns based on EPA testing data. With a grade of C- (58.1/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 3,105 residents using groundwater (wells).
Recent water quality updates for Olla
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Olla's water quality assessment. Grade: C- (58.1/100).
1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS.
Contaminants: Lead and Copper Rule.
1 health-based. Contaminants: TTHM.
Key contaminant findings
Based on the most recent EPA sampling data for Olla's water supply.
Well within EPA limits.
Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.
Violation history
Olla's water system has 48 total violations on record, including 31 health-based violations. 12 remain unresolved. 4 violations were issued in the last 5 years.
Where does Olla's water come from?
Olla's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 3,105 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Castor Creek At Tullos, La. (river), Little River At Rochelle, La. (river), Little River Near Rochelle (river).
What Olla residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Olla'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.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Olla
Industrial polluters nearby
Reported releases to surface water by facilities near Olla, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
LASALLE BIOENERGY LLC URANIA, LA71480 | — | — | 2.4 mi |
LASALLE LUMBER CO LLC - URANIA SAWMILL URANIA, LA71480 | — | — | 4.0 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Recommended water filters
Based on contaminants detected in Olla'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. | 0.0 | 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. | 2.00 | 1.3 | mg/L | Inorganic | Over Limit |
Lead level trend (90th percentile)
Copper level (90th percentile)
Latest reading: 2.000 mg/L (1994)
EPA action level: 1.3 mg/L
See how Olla compares by contaminant
Explore where Olla ranks among all Louisiana cities for specific contaminants.
Water source & infrastructure
Where Olla's water comes from
Olla's drinking water is drawn from underground aquifers through wells.
Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.
Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.
The system is operated by local government ownership and serves approximately 3,105 people through 2 water systems.
Water bodies near Olla
Olla is located near 3 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Olla
| System Name | PWSID | Population | Source |
|---|---|---|---|
| TOWN OF OLLA WATER SYSTEM | LA1059004 | 2,565 | GW |
| PLEASANT RIDGE WATER SYSTEM | LA1059006 | 540 | GWP |
How Olla compares
Full Louisiana rankings →Olla's score of 58.1/100 is above the average of 53/100 among major Louisiana cities. It outscores 7 of 10 nearby cities.
Nearby cities
View Louisiana rankings →About Olla, LA
Wikipedia →Olla is an incorporated town in northwest La Salle Parish, Louisiana, United States, located in the heart of the Louisiana Central Hill Country.
Learn more about your water
Guides and resources related to Olla's water quality findings.
Explore water quality across La Salle Parish
Frequently asked questions
Is Olla, LA tap water safe to drink?
Olla's water quality earned a grade of C- (58.1/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #182 out of 309 cities tested in Louisiana.
What contaminants are in Olla's water?
Lead was measured at 0.0 ppb (90th percentile). 48 violations are on record.
How is Olla'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 Olla?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Olla's water come from?
Olla's water is sourced from Groundwater. The city has 2 water systems serving approximately 3,105 residents.
What health violations has Olla's water system had?
Olla has 31 health-based violations on record. The most recent violation was recorded in October 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 12 violations remain unresolved.
Is Olla's groundwater at risk of contamination?
Olla 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 48 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 Olla's water compare to other cities?
Olla ranks #182 out of 309 cities in Louisiana (better than 41% of state cities) and #12310 out of 15744 cities nationally (22th percentile). The grade of C- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.