Nantucket, MA · PWSID MA4197001
Siasconset Water Department lead service lines
796 lines still unidentified
Siasconset Water Department reported no confirmed lead service lines, but 796 of 1,098 lines (72%) are still listed as "lead status unknown." Until a line is identified, treat it as possibly lead.
0% of Siasconset 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%
- Unknown 72%
- Non-lead 28%
Total service lines reported: 1,098. Reported all required service line types. Population served: 3,000; 863 connections.
Lead test results
Siasconset Water Department's most recent 90th-percentile lead result (2025) 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 0 in 2025 Q1 to 0 in 2026 Q3: no change. Lines of unknown material went from 796 to 796, 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 no Lead and Copper Rule violations for Siasconset Water Department since 2015. That covers testing, reporting, corrosion control and public notice requirements; it isn't a guarantee about any individual home.
Source: EPA SDWIS violation records for the Lead and Copper Rule.
Where the water comes from
Siasconset 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 Siasconset 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 Nantucket County
Other water systems nearby
| System | Lead + galv. | Unknown |
|---|---|---|
| Wannacomet Water Company | 168 | 6,019 |
Check another water system
Questions
Does Siasconset Water Department have lead pipes?
It hasn't confirmed any, but 796 of its 1,098 service lines are still of unknown material, so lead has not been ruled out.
How do I check if my home's service line is lead?
Look up your address on Siasconset 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 Siasconset 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 Siasconset Water Department had lead violations?
EPA's data shows no Lead and Copper Rule violations since 2015 for Siasconset 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, "Siasconset Water Department lead service lines," https://leadpipemap.com/ma/siasconset-water-department/. Source: EPA SDWIS service line inventory, 2026 Q3. Download the full dataset on the data page.