What was found in Old Lyme's water
The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate | 1930 µg/L 19% of the EPA limit 10000 µg/L Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 6957.5 µg/L — LYME REGIS, INC. · 32 people · 2019 | 10/10 | SYR4 |
| Nitrate-Nitrite | 1586 µg/L 16% of the EPA limit 10000 µg/L Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 6297.5 µg/L — LYME REGIS, INC. · 32 people · 2019 | 10/10 | SYR4 |
| Copper | 67.8 µg/L 5.2% of the EPA limit 1300 µg/L Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 1633 µg/L — BOXWOOD CONDOMINIUM ASSOCIATION · 28 people · 2019 | 10/10 | SYR4 |
| Fluoride | 157.5 µg/L 3.9% of the EPA limit 4000 µg/L Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2018
Highest in the city: 214 µg/L — LYME ACADEMY APARTMENTS,LLC · 48 people · 2019 | 5/10 | SYR4 |
| Gross Beta Particle Activity | 177 pCi/L No EPA limit set Highest in the city: RYE FIELD MANOR ELDERLY HOUSING · 78 people · 2019 | 2/10 | SYR4 |
| Barium | 22 µg/L 1.1% of the EPA limit 2000 µg/L Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2017
Highest in the city: 93.95 µg/L — CTWC - SHORELINE REGION-POINT O WOODS · 1,068 people · 2018 | 8/10 | SYR4 |
| TTHM | 17.715 µg/L 22% of the EPA limit 80 µg/L Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 44.21 µg/L — CTWC - SHORELINE REGION-POINT O WOODS · 1,068 people · 2019 | 4/10 | SYR4 |
| Nitrite | 40 µg/L 4% of the EPA limit 1000 µg/L Highest in the city: LYME REGIS, INC. · 32 people · 2019 | 6/10 | SYR4 |
| Bromoform | 1.6 µg/L No EPA limit set Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 29.92 µg/L — CTWC - SHORELINE REGION-POINT O WOODS · 1,068 people · 2019 | 5/10 | SYR4 |
| Total Haloacetic Acids (HAA5) | 3.91 µg/L 6.5% of the EPA limit 60 µg/L Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 29.4 µg/L — LYME REGIS, INC. · 32 people · 2019 | 4/10 | SYR4 |
| Dichloroacetic Acid | 2 µg/L No EPA limit set Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 23.53 µg/L — LYME REGIS, INC. · 32 people · 2016 | 3/10 | SYR4 |
| Lead | 2.9 µg/L 19% of the EPA limit 15 µg/L Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 20.575 µg/L — LAUREL HEIGHTS ASSOCIATION, INC. · 45 people · 2019 | 10/10 | SYR4 |
| Dibromoacetic Acid | 1.77 µg/L No EPA limit set Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 11.36 µg/L — LYME REGIS, INC. · 32 people · 2016 | 4/10 | SYR4 |
| Combined Uranium | 7.495 µg/L 25% of the EPA limit 30 µg/L Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 9.1628 µg/L — CTWC - SHORELINE REGION-POINT O WOODS · 1,068 people · 2019 | 5/10 | SYR4 |
| Dibromochloromethane | 4.275 µg/L No EPA limit set Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 8.69 µg/L — CTWC - SHORELINE REGION-POINT O WOODS · 1,068 people · 2019 | 5/10 | SYR4 |
| Bromodichloromethane | 5.45 µg/L No EPA limit set Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 7.3 µg/L — LYME ACADEMY APARTMENTS,LLC · 48 people · 2019 | 5/10 | SYR4 |
| Styrene | 5.775 µg/L 5.8% of the EPA limit 100 µg/L Highest in the city: LYME ACADEMY APARTMENTS,LLC · 48 people · 2019 | 1/10 | SYR4 |
| Chloroform | 5.25 µg/L No EPA limit set Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019 | 6/10 | SYR4 |
| Combined Radium (-226 And -228) | 1.6 pCi/L 32% of the EPA limit 5 pCi/L Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 3.73 pCi/L — CTWC - SHORELINE REGION-POINT O WOODS · 1,068 people · 2019 | 7/10 | SYR4 |
| Gross Alpha, Excl. Radon And U | 1.8 pCi/L 12% of the EPA limit 15 pCi/L Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2019
Highest in the city: 3.64 pCi/L — LAUREL HEIGHTS ASSOCIATION, INC. · 45 people · 2019 | 5/10 | SYR4 |
| Trichloroacetic Acid | 3.11 µg/L No EPA limit set Highest in the city: LYME REGIS, INC. · 32 people · 2016 | 2/10 | SYR4 |
| Monobromoacetic Acid | 1.93 µg/L No EPA limit set Highest in the city: CTWC - SHORELINE REGION-POINT O WOODS · 1,068 people · 2019 | 1/10 | SYR4 |
| 1,1-Dichloroethylene | 0.6000 µg/L 8.6% of the EPA limit 7 µg/L Highest in the city: LYME REGIS, INC. · 32 people · 2019 | 1/10 | SYR4 |
| Toluene | 0.5100 µg/L 0.1% of the EPA limit 1000 µg/L Highest in the city: LYME ACADEMY APARTMENTS,LLC · 48 people · 2019 | 1/10 | SYR4 |
| Arsenic | 0.5000 µg/L 5% of the EPA limit 10 µg/L Highest in the city: LYME ACADEMY APARTMENTS,LLC · 48 people · 2019 | 1/10 | SYR4 |
| Asbestos | 0.1600 MFL 2.3% of the EPA limit 7 MFL Highest in the city: MILE CREEK APARTMENTS · 60 people · 2012 | 2/10 | SYR4 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: CTWC - SHORELINE REGION-SOUND VIEW · 3,397 people · 2025
Highest in the city: 0.0050 mg/L — LYME REGIS, INC. · 32 people · 2025 | 10/10 | LCR |
Each bar shows the measured level as a share of the EPA limit: green is
well under, amber is close to it, red is over. For lead and copper the
limit applies to exactly the 90th-percentile figure shown, so red there
means a real exceedance. For everything else the limit applies to a
running annual average while the figure is the 95th percentile of the
system's samples — over 100% is worth reading, but is not by itself a
violation.
Formal violations are listed separately.
These are the utilities' own EPA-reported results, not a city-wide
average. A detection means the lab measured the
substance — it isn't the same as exceeding a legal limit. Hover a source
tag to see the EPA program and years behind each figure.
Water suppliers serving Old Lyme
| Supplier | Population served |
|---|---|
| CTWC - SHORELINE REGION-SOUND VIEW | 3,397 |
| CTWC - SHORELINE REGION-POINT O WOODS | 1,068 |
| CHADWICK HOMEOWNERS ASSN., INC. | 292 |
| RYE FIELD MANOR ELDERLY HOUSING | 78 |
| MILE CREEK APARTMENTS | 60 |
| LYMEWOOD ELDERLY HOUSING | 50 |
| LYME ACADEMY APARTMENTS,LLC | 48 |
| LAUREL HEIGHTS ASSOCIATION, INC. | 45 |
| LYME REGIS, INC. | 32 |
| BOXWOOD CONDOMINIUM ASSOCIATION | 28 |
Frequently asked questions about Old Lyme tap water
Is Old Lyme tap water safe to drink?
EPA testing detected 27 contaminants in the water serving Old Lyme. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.
How many water suppliers serve Old Lyme?
10 public water suppliers report drinking-water monitoring for Old Lyme, Connecticut to the EPA. Each is listed above with its population served.
What contaminants are in Old Lyme's water?
The contaminants EPA monitoring detected in Old Lyme include Nitrate, Nitrate-Nitrite, Copper, Fluoride, Gross Beta Particle Activity. The full list, with the level at the main supplier and the data source, is in the table above.
Where does this data come from?
Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.