Short answer: In the records we hold for Ottawa, no listed result is above a legal limit, but a health-based violation is on record (EPA SDWIS). Also worth knowing: lithium sits above a screening level. 1 substance was detected and 30 were tested and not detected. The water is from Ottawa, serving 18,097 residents.
No measured result is above a legal limit; lithium sits above a screening level, and a past health-based violation (Combined radium-226/228) is on record.
What we found
2 detected results, by distance from their limit
Each bar runs to the named reference; the tick marks it. Open a row for five layers: measured, compared, meaning, where it matters, what to do.
OTTAWA (EPA PWSID IL0990800) delivers groundwater to 18,097 residents. This report reflects 29 individual PFAS result(s) from the source UCMR5 observations and the latest Lead & Copper Rule 90th-percentile result. Water hardness and disinfectant type are pending the utility's own annual report.
Track record
1health-based violation in the last 10 years
From EPA SDWIS. Counted once per contaminant per year, as in the Track record score.
Not in this recordDisinfection by-products weren't monitored in this dataset
No result is not a pass. Your utility's annual water quality report may list them, and a certified lab test covers your own tap.
Health-based violations, last 10 years
Every filing is listed; the Track record score counts at most one per contaminant per year.
The record describes water leaving treatment and samples across the system. Pipes, solder and fixtures inside a building can add lead the record can’t see, especially in older buildings with lead service lines.
Each card names which Ottawa findings its current certification covers, and which it doesn't.
As an Amazon Associate, PurityMap earns from qualifying purchases. A product appears here only when a current certification record covers at least one identified concern; every concern stays listed. The retail offer is looked up afterwards and never changes which products appear or their order. Affiliate disclosure.
Water Pitcher
Brita Elite Water Filter Pitcher
✓Lead: eligible, evidence match
–Not established: Lithium
Not suitable for (3)
Treating every tap in the home
A whole-home hard-water or scale problem
All PFAS: its evidence covers only the compounds it names
Ottawa reported 59 lead service lines to replace in EPA’s inventory (2026Q2). Many utilities replace these lines for free or share the cost. Ask Ottawa whether your home’s line is on its list before you pay anyone.
Your path: I live in an older buildingLead from plumbing is the main question
Older buildings may have lead service lines, solder or fixtures. Ottawa’s utility reported 59 lead service lines in EPA’s inventory. Test first-draw water, then filter if needed.
Your path: My water tastes of chlorineThe disinfectant is not in this record
Most utilities keep chlorine or chloramine in the pipes. A carbon filter certified for taste and odor reduces either; your utility can tell you which it uses.
PurityMap does not give a safe/unsafe verdict; it shows what the public records measured. For Ottawa, no regulated PFAS were detected in EPA's 2024 testing; one health-based violation is on record (Combined radium-226/228). OTTAWA (PWSID IL0990800) has a Purity Score of 99/100 (confidence: moderate), assessed at the water-system level and computed only from contaminants that were measured. Water can change in your own pipes, so a certified test is the only way to know what comes out of your tap. What we found →
Who provides tap water in Ottawa?+
OTTAWA (PWS ID IL0990800) is the public water system on record for Ottawa, Illinois, serving about 18,097 people. Confirm the utility on your water bill before acting on a specific finding. Water utility →
Where does Ottawa get its drinking water?+
Groundwater (primary source of record in EPA SDWIS). Water utility →
Are PFAS "forever chemicals" in Ottawa's water?+
None of the 29 PFAS in EPA's UCMR 5 testing (2025-03-11 to 2025-10-16) was detected. "Not detected" means below the lab's reporting limit, not proven zero. What we found →
Is there lead in Ottawa's tap water?+
Lead is not in Ottawa's current published record. Lead usually enters from a building's own pipes and fixtures, so a certified home test is the way to know yours. Your household →
Has Ottawa's water system had violations?+
The federal SDWIS record lists a health-based violation for OTTAWA within about the last ten years: Combined radium-226/228 (2023). The findings above show each one's status. At a glance →
What does the latest Ottawa water report show?+
PurityMap's current record for Ottawa holds 32 findings: 2 above a reference and 30 not detected. Each finding links to its dated public record; a parameter that was never monitored is shown as pending, not as a pass. Records →
EPA SDWIS, EPA UCMR 5 and utility reports, each dated and linked.
02Normalize
Units converted to one basis; a non-detect kept distinct from zero.
03Classify
Each result tagged by reference type: MCL, action level, screening level or aesthetic.
04Compare to the named reference
Every value sits against its own reference, never a blended one.
05Score
Measured subjects summarised at the water-system level; an open health-based violation caps the score.
06Match treatment
Treatment is matched to what was found; a product is called certified only when its current certification names it.
What the Purity Score means: a summary of this water system’s published record, capped while a health-based violation is open. It is not a test of any tap. OTTAWA · PWSID IL0990800 · Purity Score 99/100 (Excellent) · Confidence: moderate · Assessed at the water-system level
Lead at Ottawa: not detected (90th percentile, 2026–2028 monitoring period (still open)). Lead has no taste, so a taste neither shows nor rules it out.
ZIP codes in Ottawa
A ZIP code is a postal area, not a water service area. Your water bill names your supplier.
