Ctwc - Northern Reg-Western System, CT
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (monitoring period 2026-2026). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. The latest 90th-percentile result was reported as 0 (not detected at the lab's limit). That says the sampled homes were low, not that your home has no lead service line. Check your utility's service line inventory for your address.
About Ctwc - Northern Reg-Western System
Ctwc - Northern Reg-Western System serves about 101,313 people through 37,354 service connections, which makes it a very large system under EPA's size classes. It is privately owned and draws surface water, in Hartford County, Connecticut. EPA system ID: CT0473011; phone on file: 860-944-9655. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Lead results over time
That is down 1.9 ppb from 1.9 ppb in the period ending 2026. The highest 90th-percentile result EPA holds for Ctwc - Northern Reg-Western System is 14 ppb across 30 monitoring periods, none of them over 15 ppb (3 over 10 ppb).
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 0 (not detected) |
| 2026 | 1.9 ppb |
| 2025 | 1.6 ppb |
| 2025 | 0 (not detected) |
| 2025 | 0 (not detected) |
| 2024 | 1.7 ppb |
| 2024 | 0 (not detected) |
| 2024 | 2 ppb |
| 2023 | 1.4 ppb |
| 2023 | 0 (not detected) |
| 2023 | 10.3 ppb over 10 |
| 2022 | 3.3 ppb |
| 2022 | 0 (not detected) |
| 2022 | 4.5 ppb |
| 2021 | 2 ppb |
| 2021 | 0 (not detected) |
| 2021 | 4 ppb |
| 2020 | 3 ppb |
| 2020 | 0 (not detected) |
| 2020 | 7 ppb |
| 2019 | 2 ppb |
| 2019 | 0 (not detected) |
| 2019 | 14 ppb over 10 |
| 2018 | 2 ppb |
| 2018 | 0 (not detected) |
| 2018 | 10.2 ppb over 10 |
| 2017 | 2.5 ppb |
| 2017 | 0 (not detected) |
| 2016 | 2 ppb |
| 2016 | 0 (not detected) |
Where this result ranks
Of the 493 Connecticut systems with a lead result, the median latest reading is 0.8 ppb; 2 are over 15 ppb right now and 49 have gone over at some point. Ctwc - Northern Reg-Western System's reported as 0 (not detected) sits at the 40th percentile in Connecticut and the 40th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Nearby utilities
46 other systems share Hartford County; 23 of them have a higher latest lead result than Ctwc - Northern Reg-Western System. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Metropolitan District Commission | 390,887 | 0 (not detected) |
| New Britain Water Department | 73,534 | 0 (not detected) |
| Bristol Water Department | 52,079 | 0 (not detected) |
| Manchester Water Department | 51,198 | 0 (not detected) |
| Southington Water Department | 43,069 | 0 (not detected) |
| Hazardville Water Company | 18,544 | 0.7 ppb |
| Aquarion-Plainville Regional | 18,231 | 0 (not detected) |
| Ctwc - Unionville System | 14,693 | 2.4 ppb |
| Aquarion-Simsbury Regional | 14,691 | 0.3 ppb |
| Avon Water Co | 11,590 | 0 (not detected) |
What to do in your house
Look up your address in Ctwc - Northern Reg-Western System's service line inventory. If it says lead, galvanized or unknown, test your tap. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Ctwc - Northern Reg-Western System whether it covers that cost before hiring anyone - many utilities now do.
These figures describe homes the utility sampled, not your tap. Only your service line record or a test of your own water answers the question for your house. The lead result guide covers how utilities pick the homes they sample. Small systems behave differently: why small systems go over more often.