New Jersey · population 4,644
Lead pipes in Mountain Lakes, NJ
688 lead or galvanized lines to replace
Most of Mountain Lakes (population 4,644) gets its water from Mountain Lakes Water Dep. That system reported 0 lead and 688 galvanized-requiring-replacement service lines out of 1,499, with 93 more of unknown material.
46% of Mountain Lakes Water Dep's service lines are lead or galvanized requiring replacement, higher than the New Jersey average (4.5%) and higher than the national average (3.1%).
- Lead 0%
- Galvanized (replace) 46%
- Unknown 6.2%
- Non-lead 48%
Latest lead test for Mountain Lakes Water Dep (Jan 2023–Dec 2025): 2.5 ppb at the 90th percentile, against a 15 ppb federal action level. Full test history.
Compliance record: EPA lists 1 Lead and Copper Rule violation since 2015 for Mountain Lakes Water Dep.
Water systems serving Mountain Lakes
| Water system | Lead | Galv. | Unknown | % lead |
|---|---|---|---|---|
| Mountain Lakes Water DepMain system | 0 | 688 | 93 | 46% |
| Denville TWP Water DeptServes nearby areas | 0 | 195 | 4,871 | 3.3% |
Matched from EPA water system service area boundaries and the cities each system reports serving. Edges of the city may be served by a neighboring system; your water bill names your utility.
Check your address in Mountain Lakes
The counts above cover the whole water system. To see whether your line is lead, look up your address on Mountain Lakes Water Dep's official inventory. Utilities had to make these public by October 16, 2024.
No map yet? Do the 2-minute scratch and magnet test.
Protect your drinking water
If your line is lead, galvanized or unknown, use a filter certified to NSF/ANSI 53 for lead for drinking, cooking and baby formula, and use only cold water.
Choosing a lead-certified filter · Testing your water · Replacement cost
Nearby cities
- Boonton118 lead + galv. lines
- Rockaway6 lead + galv. lines
- Morris Plains769 lead + galv. lines
- Victory Gardens314 lead + galv. lines
- Dover314 lead + galv. lines
- Morristown769 lead + galv. lines
- Wharton150 lead + galv. lines
- Kinnelon3 lead + galv. lines
Check another water system
Questions
Does Mountain Lakes, NJ have lead pipes?
Yes. Mountain Lakes Water Dep, which serves Mountain Lakes, reported 0 lead and 688 galvanized-requiring-replacement service lines, plus 93 of unknown material.
Who supplies water to Mountain Lakes?
EPA's service area maps place most of Mountain Lakes in Mountain Lakes Water Dep's service area (PWSID NJ1425001). Denville TWP Water Dept also serves parts of the city or nearby areas.
How do I check whether my Mountain Lakes home has a lead service line?
Search your address on Mountain Lakes Water Dep's service line inventory map. You can also scratch the pipe where water enters your home: lead is soft, dull gray, scratches to shiny silver and doesn't attract a magnet.
When will lead pipes in Mountain Lakes be replaced?
EPA's Lead and Copper Rule Improvements require most systems to replace lead and galvanized-requiring-replacement lines by December 31, 2037. Ask Mountain Lakes Water Dep whether your street is scheduled and whether it covers the private side.