Aquarion-Interlaken, CT
Lead detected, under the action levels
Latest 90th-percentile lead: 3 ppb (monitoring period 2021-2023). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. Lead was measured in sampled homes but the 90th percentile is under both action levels. EPA's health goal for lead is zero, so test your own tap if your home was built before 1986 or anyone in it is pregnant or a young child.
About Aquarion-Interlaken
Aquarion-Interlaken serves about 64 people through 16 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Fairfield County, Connecticut. EPA system ID: CT0911061; phone on file: 203-926-4320. They can tell you what your service line is made of and whether they pay to replace it.
Lead results over time
That is up 2 ppb from 1 ppb in the period ending 2020. The highest 90th-percentile result EPA holds for Aquarion-Interlaken is 3 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2023 | 3 ppb |
| 2020 | 1 ppb |
| 2019 | 1 ppb |
Against other Connecticut systems
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. Aquarion-Interlaken's 3 ppb sits at the 84th percentile in Connecticut and the 81st nationally (higher means more lead).
Other water systems in Fairfield County
58 other systems share Fairfield County; 11 of them have a higher latest lead result than Aquarion-Interlaken. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Aquarion-Eastern Fairfield County | 351,756 | 0 (not detected) |
| Aquarion-Stamford | 119,214 | 0 (not detected) |
| Danbury Water Department | 62,055 | 0 (not detected) |
| Aquarion-Greenwich | 53,297 | 0 (not detected) |
| South Norwalk Electric & Water | 42,000 | 0 (not detected) |
| Norwalk First Taxing District | 40,256 | 0 (not detected) |
| Aquarion-Darien | 18,737 | 2 ppb |
| Aquarion-New Canaan | 10,097 | 0 (not detected) |
| Bethel Water Dept | 9,507 | 0 (not detected) |
| Aquarion-Ridgefield | 7,476 | 3.1 ppb |
Next steps for Shelton, CT
Test your own tap with a certified lab first-draw sample; Shelton, CT may offer free or low-cost kits through the utility. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Aquarion-Interlaken 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. Size matters more than most people expect: small vs large water systems.