Middlesex Water Company, NJ
Lead detected, under the action levels
Latest 90th-percentile lead: 0.85 ppb (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. 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.
Who runs the water here
Middlesex Water Company serves about 233,376 people through 58,344 service connections, which makes it a very large system under EPA's size classes. It is privately owned and draws surface water, in Middlesex County, New Jersey. EPA system ID: NJ1225001; phone on file: 732-638-7537. They can tell you what your service line is made of and whether they pay to replace it.
Every lead result on file
Against the period ending 2025 (0.98 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Middlesex Water Company is 6.71 ppb across 18 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 0.85 ppb |
| 2025 | 0.98 ppb |
| 2025 | 1.08 ppb |
| 2024 | 0.62 ppb |
| 2024 | 0.85 ppb |
| 2023 | 1.22 ppb |
| 2023 | 1.22 ppb |
| 2022 | 1.99 ppb |
| 2022 | 6.71 ppb |
| 2021 | 0.86 ppb |
| 2021 | 1.02 ppb |
| 2020 | 0.97 ppb |
| 2020 | 1.65 ppb |
| 2019 | 0.92 ppb |
| 2018 | 1.4 ppb |
| 2017 | 0.73 ppb |
| 2017 | 1.33 ppb |
| 2016 | 2 ppb |
Where this result ranks
Of the 605 New Jersey systems with a lead result, the median latest reading is 1 ppb; 5 are over 15 ppb right now and 52 have gone over at some point. Middlesex Water Company's 0.85 ppb sits at the 47th percentile in New Jersey and the 48th nationally (higher means more lead).
Nearby utilities
13 other systems share Middlesex County; 7 of them have a higher latest lead result than Middlesex Water Company. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Old Bridge Mua | 68,000 | 1.75 ppb |
| New Brunswick W Dept | 55,000 | 1.78 ppb |
| Perth Amboy Water Department | 52,328 | 0 (not detected) |
| East Brunswick Water Utility | 49,715 | 0.4 ppb |
| Sayreville W Dept | 45,345 | 0.54 ppb |
| North Brunswick W Dept | 43,905 | 2.4 ppb |
| Monroe Twp Utility Department | 36,000 | 1.34 ppb |
| Edison Water Co | 35,000 | 1.18 ppb |
| South River W Dept | 16,000 | 0 (not detected) |
| Highland Park W Dept | 14,000 | 0.63 ppb |
Your move
Test your own tap with a certified lab first-draw sample; Iselin, NJ 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 Middlesex Water Company 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. Why sampled homes are the worst-case ones is in the guide to reading the number. Systems that went over once often dip back under; here is what that means.