Holliston, MA · PWSID MA2136000
Holliston Water Department lead service lines
1 lead or galvanized lines to replace
Holliston Water Department reported 0 lead and 1 galvanized-requiring-replacement service lines out of 5,203 in its inventory. That's about 1 in 5,203 lines. Another 3,821 (73%) are still listed as unknown material.
Ranks #163 of 175 Massachusetts systems with confirmed lead lines, and #6,746 nationally.
<0.1% of Holliston Water Department's service lines are lead or galvanized requiring replacement. That's lower than the Massachusetts average (2.2%) and lower than the national average (3.1%).
- Lead 0%
- Galvanized (replace) <0.1%
- Unknown 73%
- Non-lead 27%
Total service lines reported: 5,203. Reported all required service line types. Population served: 15,139; 5,018 connections.
Lead test results
Holliston Water Department's most recent 90th-percentile lead result (2025) was 2.9 ppb, 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 1 in 2025 Q1 to 1 in 2026 Q3: no change. Lines of unknown material went from 3,821 to 3,821, no change.
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 4 Lead and Copper Rule violations since 2015, 2 still open for Holliston Water Department. Health-based violations are treatment failures, such as corrosion control or public education; the rest are missed monitoring or reporting.
| Began | Violation | Status |
|---|---|---|
| Oct 2024 | Missed follow-up or routine lead and copper tap sampling | Open |
| Apr 2023 | Lead consumer notice not delivered or reported | Open |
| Dec 2016 | Lead consumer notice not delivered or reported | Returned to compliance |
| Oct 2015 | Missed follow-up or routine lead and copper tap sampling | Returned to compliance |
Source: EPA SDWIS violation records for the Lead and Copper Rule.
Where the water comes from
Holliston Water Department's main water source is groundwater (wells).
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 Holliston Water Department 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 Middlesex County
ZIP codes served
ZIP codes whose center falls inside Holliston Water Department's mapped service area (EPA service area boundaries). Neighboring utilities may serve parts of the same ZIP.
01746
Other water systems nearby
| System | Lead + galv. | Unknown |
|---|---|---|
| Lowell Regional Water Utility | 287 | 1,558 |
| Cambridge Water Department | 2,195 | 104 |
| Malden Water Division (Mwra) | 2,470 | 689 |
| Medford Water Dept. (Mwra) | 5,130 | 4,657 |
| Everett Water Dept. (Mwra) | 1,073 | 1,428 |
| Marlborough DPW Water Div. (Mwra) | 313 | 1,503 |
| Lexington Water Dept. (Mwra) | 333 | 78 |
| Melrose Water Division (Mwra) | 423 | 263 |
Check another water system
Questions
Does Holliston Water Department have lead pipes?
Yes. Holliston Water Department reported 0 lead service lines and 1 galvanized lines that must be replaced, out of 5,203 total. 3,821 more are of unknown material.
How do I check if my home's service line is lead?
Look up your address on Holliston Water Department'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 Holliston Water Department 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 Holliston Water Department had lead violations?
EPA's data shows 4 Lead and Copper Rule violations since 2015, 2 still open for Holliston Water Department.
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, "Holliston Water Department lead service lines," https://leadpipemap.com/ma/holliston-water-department/. Source: EPA SDWIS service line inventory, 2026 Q3. Download the full dataset on the data page.