Hamilton Twp., NJ · PWSID NJ1103001
Aqua NJ - Hamilton Square lead service lines
22 lead or galvanized lines to replace
Aqua NJ - Hamilton Square reported 1 lead and 21 galvanized-requiring-replacement service lines out of 16,220 in its inventory. That's about 1 in 737 lines. Another 518 (3.2%) are still listed as unknown material.
Ranks #146 of 240 New Jersey systems with confirmed lead lines, and #3,562 nationally.
0.1% of Aqua NJ - Hamilton Square's service lines are lead or galvanized requiring replacement. That's lower than the New Jersey average (4.5%) and lower than the national average (3.1%).
- Lead <0.1%
- Galvanized (replace) 0.1%
- Unknown 3.2%
- Non-lead 97%
Total service lines reported: 16,220. Reported all required service line types. Population served: 39,128; 12,738 connections.
Lead test results
Aqua NJ - Hamilton Square's most recent 90th-percentile lead result (Jan 2024–Dec 2026) was not detected, below both the 15 ppb action level and the 10 ppb level that takes effect in 2027. This means 90% of homes sampled were at or below that level; individual homes, especially those with lead lines, can be higher.
Lead and Copper Rule 90th-percentile results reported to EPA, in parts per billion. Dashed lines: 15 ppb action level and the 10 ppb level from November 1, 2027.
Progress since 2025 Q1
Reported lead and galvanized-requiring-replacement lines went from 19 in 2025 Q1 to 22 in 2026 Q3: up 3 (16%). Lines of unknown material went from 627 to 518, down 109 (17%).
Quarterly counts reported to EPA. A drop usually means lines were replaced or confirmed non-lead; a rise usually means more lines were identified. Replacement progress rankings.
Lead rule violations
EPA's data lists 6 Lead and Copper Rule violations since 2015, 1 still open for Aqua NJ - Hamilton Square. Health-based violations are treatment failures, such as corrosion control or public education; the rest are missed monitoring or reporting.
| Began | Violation | Status |
|---|---|---|
| Jul 2024 | Missed water quality parameter monitoring | Closed |
| Dec 2023 | Lead consumer notice not delivered or reported | Open |
| Jul 2023 | Missed water quality parameter monitoring | Closed |
| Jul 2021 | Missed water quality parameter monitoring | Returned to compliance |
| Jul 2019 | Missed water quality parameter monitoring | Returned to compliance |
| Jan 2019 | Missed water quality parameter monitoring | Returned to compliance |
Source: EPA SDWIS violation records for the Lead and Copper Rule.
Where the water comes from
Aqua NJ - Hamilton Square's main water source is purchased surface water. It buys treated water from Trenton Water Works. The seller treats the water, including corrosion control that keeps lead from dissolving out of pipes, while Aqua NJ - Hamilton Square is responsible for its own service line inventory and replacement program. It sells water to 2 other water systems: Trenton Water Works, Robbinsville TWP - Newtown Village.
Source: EPA SDWIS water system and facility records.
Check your own address
These counts cover the whole system. To see whether your line is lead, use the utility's address-level inventory. Utilities had to prepare one by October 16, 2024 and make it publicly accessible; systems serving more than 50,000 people must post it online.
No map yet? Do the 2-minute scratch and magnet test on the pipe where water enters your home.
Protect your drinking water now
If your line is lead, galvanized or unknown, filter water for drinking, cooking and baby formula. Use a filter certified to NSF/ANSI 53 for lead. Run cold water for a few minutes after it sits for hours, and never use hot tap water for cooking.
How to pick a lead-certified filter · How to test your water for lead
Getting the line replaced
EPA's Lead and Copper Rule Improvements require most systems to replace lead and galvanized-requiring-replacement lines by December 31, 2037. Ask Aqua NJ - Hamilton Square whether it replaces the private side for free or with a cost share before you hire anyone. If you want it done sooner, or your utility doesn't cover your side, a licensed plumber can quote it. What replacement costs.
County pages: Lead pipes in Mercer County
ZIP codes served
ZIP codes whose center falls inside Aqua NJ - Hamilton Square's mapped service area (EPA service area boundaries). Neighboring utilities may serve parts of the same ZIP.
0862008690
Other water systems nearby
| System | Lead + galv. | Unknown |
|---|---|---|
| Trenton Water Works | 16,180 | 23,000 |
| East Windsor Mua | 0 | 0 |
| Aqua NJ - Lawrence | 38 | 16 |
| Hightstown Water Department | 0 | 697 |
| Pennington W Dept | 154 | 0 |
| Hopewell Boro W Dept | 46 | 3 |
| Lawrenceville School | 0 | 0 |
Check another water system
Questions
Does Aqua NJ - Hamilton Square have lead pipes?
Yes. Aqua NJ - Hamilton Square reported 1 lead service lines and 21 galvanized lines that must be replaced, out of 16,220 total. 518 more are of unknown material.
How do I check if my home's service line is lead?
Look up your address on Aqua NJ - Hamilton Square's official service line inventory, which utilities must make publicly available. You can also scratch the pipe where it enters your home: lead is soft, dull gray, scratches to shiny silver and does not attract a magnet.
When will Aqua NJ - Hamilton Square replace lead service lines?
Under EPA's Lead and Copper Rule Improvements, most systems must replace lead and galvanized-requiring-replacement lines by December 31, 2037, starting from November 1, 2027. The rule is being challenged in court, so dates could change. Many utilities run free or cost-share programs now.
Has Aqua NJ - Hamilton Square had lead violations?
EPA's data shows 6 Lead and Copper Rule violations since 2015, 1 still open for Aqua NJ - Hamilton Square.
Which water filters remove lead?
Use a filter certified to NSF/ANSI Standard 53 for lead reduction, or NSF/ANSI 58 for reverse osmosis. Check the certification on NSF's listings, not just the box.
Embed or cite this data
Local news sites, blogs and community groups can embed this card. It updates when EPA releases new data.
Citation: Lead Pipe Map, "Aqua NJ - Hamilton Square lead service lines," https://leadpipemap.com/nj/aqua-nj-hamilton-square/. Source: EPA SDWIS service line inventory, 2026 Q3. Download the full dataset on the data page.