Wellesley Water Division

Published drinking-water records and contacts for Wellesley Water Division. System MA3317000. Review sources and dates; not a real-time water assessment.

System ID: MA3317000
State or territory: MA
Published population served: 29550
System type (source code): CWS

Published records and dates

PFAS / lithium (EPA UCMR 5): 300 — 2025-01-21 – 2025-10-01
Lead and copper monitoring summaries: 25 — 1992-07-01 – 2025-12-31
Massachusetts EEA PFAS monitoring results: 6303 — 2021-04-21 – 2026-09-09

Missing records here do not mean the provider did not test. Published records are not a real-time assessment of your tap water.

Read the provider’s annual water quality report

Report link listed: 2026-10-09. This is not the report’s sampling date.

Published testing results

Selected recent records are shown below. Different sampling locations and dates are not interchangeable. These excerpts are not a complete testing history.

“<” means below the stated reporting limit, not zero. A reported measurement alone is not a safety verdict. Read an example

EPA UCMR 5 — most recent imported sample per substance
Substance	Published result	Reporting limit	Sample date	Sampling location
11Cl-PF3OUdS	< 0.005 µg/L	0.005 µg/L	2025-10-01	MWRA Connection / EP002
4:2 FTS	< 0.003 µg/L	0.003 µg/L	2025-10-01	MWRA Connection / EP002
6:2 FTS	< 0.005 µg/L	0.005 µg/L	2025-10-01	MWRA Connection / EP002
8:2 FTS	< 0.005 µg/L	0.005 µg/L	2025-10-01	MWRA Connection / EP002
9Cl-PF3ONS	< 0.002 µg/L	0.002 µg/L	2025-10-01	MWRA Connection / EP002
ADONA	< 0.003 µg/L	0.003 µg/L	2025-10-01	MWRA Connection / EP002
HFPO-DA	< 0.005 µg/L	0.005 µg/L	2025-10-01	MWRA Connection / EP002
NEtFOSAA	< 0.005 µg/L	0.005 µg/L	2025-10-01	MWRA Connection / EP002
NFDHA	< 0.02 µg/L	0.02 µg/L	2025-10-01	MWRA Connection / EP002
NMeFOSAA	< 0.006 µg/L	0.006 µg/L	2025-10-01	MWRA Connection / EP002
PFBA	< 0.005 µg/L	0.005 µg/L	2025-10-01	MWRA Connection / EP002
PFBS	< 0.003 µg/L	0.003 µg/L	2025-10-01	MWRA Connection / EP002
PFDA	< 0.003 µg/L	0.003 µg/L	2025-10-01	MWRA Connection / EP002
PFDoA	< 0.003 µg/L	0.003 µg/L	2025-10-01	MWRA Connection / EP002
PFEESA	< 0.003 µg/L	0.003 µg/L	2025-10-01	MWRA Connection / EP002
PFHpA	< 0.003 µg/L	0.003 µg/L	2025-10-01	MWRA Connection / EP002
PFHpS	< 0.003 µg/L	0.003 µg/L	2025-10-01	MWRA Connection / EP002
PFHxA	< 0.003 µg/L	0.003 µg/L	2025-10-01	MWRA Connection / EP002
PFHxS	< 0.003 µg/L	0.003 µg/L	2025-10-01	MWRA Connection / EP002
PFMBA	< 0.003 µg/L	0.003 µg/L	2025-10-01	MWRA Connection / EP002
PFMPA	< 0.004 µg/L	0.004 µg/L	2025-10-01	MWRA Connection / EP002
PFNA	< 0.004 µg/L	0.004 µg/L	2025-10-01	MWRA Connection / EP002
PFOA	< 0.004 µg/L	0.004 µg/L	2025-10-01	MWRA Connection / EP002
PFOS	< 0.004 µg/L	0.004 µg/L	2025-10-01	MWRA Connection / EP002
PFPeA	< 0.003 µg/L	0.003 µg/L	2025-10-01	MWRA Connection / EP002
PFPeS	< 0.004 µg/L	0.004 µg/L	2025-10-01	MWRA Connection / EP002
PFTA	< 0.008 µg/L	0.008 µg/L	2025-10-01	MWRA Connection / EP002
PFTrDA	< 0.007 µg/L	0.007 µg/L	2025-10-01	MWRA Connection / EP002
PFUnA	< 0.002 µg/L	0.002 µg/L	2025-10-01	MWRA Connection / EP002
lithium	< 9 µg/L	9 µg/L	2025-10-01	MWRA Connection / EP002

Download all EPA UCMR 5 records (CSV)

Lead and copper: 90th-percentile summaries

These describe a monitoring period across sampled locations, not the result at your home. How to read the 90th percentile

Eight most recent imported monitoring summaries
Substance	Published 90th percentile	Monitoring period	Source quarter
Lead (PB90)	0.0035 mg/L	2025-07-01 – 2025-12-31	2026Q3
Lead (PB90)	0.0044 mg/L	2025-01-01 – 2025-06-30	2026Q3
Lead (PB90)	0.004 mg/L	2024-07-01 – 2024-12-31	2026Q3
Lead (PB90)	0.0046 mg/L	2023-07-01 – 2023-12-31	2026Q3
Lead (PB90)	0.0046 mg/L	2023-01-01 – 2023-06-30	2026Q3
Lead (PB90)	0.005 mg/L	2022-07-01 – 2022-12-31	2026Q3
Lead (PB90)	0.0054 mg/L	2019-01-01 – 2021-12-31	2026Q3
Lead (PB90)	0.004 mg/L	2016-01-01 – 2018-12-31	2026Q3

Twelve most recent imported state laboratory records
Substance	Published result	Sample date	Location / source
HEXAFLUOROPROPYLENE OXIDE DIMER ACID - HFPO-DA	Below a limit; numeric threshold unavailable ng/L	2026-09-09	ION EXCHANGE VESSEL 1 EFFLUENT / Massachusetts EEA PFAS monitoring results
PERFLUOROTETRADECANOIC ACID - PFTA	Below a limit; numeric threshold unavailable ng/L	2026-09-09	ION EXCHANGE VESSEL 2 EFFLUENT / Massachusetts EEA PFAS monitoring results
N-METHYL PERFLUOROOCTANESULFONAMIDOACETIC ACID - NMEFOSAA	Below a limit; numeric threshold unavailable ng/L	2026-09-09	ION EXCHANGE VESSEL 2 EFFLUENT / Massachusetts EEA PFAS monitoring results
N-ETHYL PERFLUOROOCTANESULFONAMIDOACETIC ACID - NETFOSAA	Below a limit; numeric threshold unavailable ng/L	2026-09-09	ION EXCHANGE VESSEL 2 EFFLUENT / Massachusetts EEA PFAS monitoring results
PERFLUOROHEXANESULFONIC ACID-PFHXS	Below a limit; numeric threshold unavailable ng/L	2026-09-09	ION EXCHANGE VESSEL 1 EFFLUENT / Massachusetts EEA PFAS monitoring results
PERFLUORODODECANOIC ACID - PFDOA	Below a limit; numeric threshold unavailable ng/L	2026-09-09	ION EXCHANGE VESSEL 1 EFFLUENT / Massachusetts EEA PFAS monitoring results
PERFLUOROTRIDECANOIC ACID - PFTRDA	Below a limit; numeric threshold unavailable ng/L	2026-09-09	WELLESLEY AVE. WTP / Massachusetts EEA PFAS monitoring results
PERFLUORODODECANOIC ACID - PFDOA	Below a limit; numeric threshold unavailable ng/L	2026-09-09	WELLESLEY AVE. WTP / Massachusetts EEA PFAS monitoring results
PERFLUOROTETRADECANOIC ACID - PFTA	Below a limit; numeric threshold unavailable ng/L	2026-09-09	WELLESLEY AVE. WTP / Massachusetts EEA PFAS monitoring results
11-CHLOROEICOSAFLUORO-3-OXAUNDECANE-1-SULFONIC ACID-11CL-PF3OUDS	Below a limit; numeric threshold unavailable ng/L	2026-09-09	WELLESLEY AVE. WTP / Massachusetts EEA PFAS monitoring results
9-CHLOROHEXADECAFLUORO-3-OXANONE-1-SULFONIC ACID-9CL-PF3ONS	Below a limit; numeric threshold unavailable ng/L	2026-09-09	WELLESLEY AVE. WTP / Massachusetts EEA PFAS monitoring results
PERFLUOROUNDECANOIC ACID - PFUNA	Below a limit; numeric threshold unavailable ng/L	2026-09-09	MORSES POND GAC EFFLUENT / Massachusetts EEA PFAS monitoring results

State sampling points can include untreated water. Publisher qualifiers and units are retained; consult the full source notes before interpreting a record.

Download state records with source notes (CSV)

Published compliance history

5 imported records. Status is as recorded in the source; historical records are not current advisories. Missing records do not establish that no violations occurred.

Twenty most recent imported compliance records
Rule / record	Period	Recorded status	Health-based (EPA classification)	Source quarter
Lead and Copper Rule / Lead Consumer Notice	2022-07-01 – —	Addressed	No	2026Q3
Total Coliform Rule / Monitoring, Routine Major (TCR)	2008-05-01 – 2008-05-31	Archived	No	2026Q3
Total Coliform Rule / Maximum Contaminant Level Violation, Monthly (TCR)	2002-08-01 – 2002-08-31	Archived	Yes	2026Q3
Total Coliform Rule / Maximum Contaminant Level Violation, Monthly (TCR)	1997-06-01 – 1997-06-30	Archived	Yes	2026Q3
Total Coliform Rule / Maximum Contaminant Level Violation, Monthly (TCR)	1991-07-01 – 1991-07-31	Archived	Yes	2026Q3

Source dates and refresh checks

A refresh check is not a sample date. Publication periods, sample dates and checks are shown separately.

EPA SDWIS lead/copper summaries and service areas — source period: — – —; last checked: 2026-10-17
EPA SDWIS contacts and compliance records — source period: — – —; last checked: 2026-10-17
EPA UCMR 5 sample results — source period: 2023-01-03 – 2026-06-17; last checked: 2026-10-17
Massachusetts EEA PFAS monitoring results — last successful check: 2026-10-12

Administrative contact (EPA filing)

Wellesley Water Division: 7812357600

An administrative filing contact may not be a customer-service line. Confirm current contact details with the provider.

Official state resources · How to read these records