Emerald Lake

PWSID: NH1141020

1 active health-based violation
This system currently has unresolved violations for: 0700. These violations mean contaminant levels exceeded EPA limits or required treatment was not performed.

This system has more violations on record than 92% of water systems in New Hampshire.

Violation trend: 0.8 per year over the last 5 years, down from 1.6 per year in the previous 5.

System Details

Population Served1,300
Service Connections528
Water SourceGroundwater
System TypeCommunity Water System
OwnerLocal Government
StatusActive
CityHillsboro
EPA ZIP on File03244

Areas Served

  • Hillsborough, Hillsborough

2 Active Violations

ContaminantViolationDateHealth-BasedStatus
0700TT2020-10-02YesOpen
7500Other
Measured: 0 mg/L
2002-01-27Open

Violation History (22 total)

ContaminantViolationDateHealth-BasedStatus
2950MR2024-07-01Returned to Compliance
2456MR2024-07-01Returned to Compliance
8000RPT2021-11-10Returned to Compliance
8000MON2021-10-01 MajorReturned to Compliance
7500Other2020-01-23Returned to Compliance
1005MCL
Measured: 0.0130 MG/L (EPA limit: 0.010 mg/L)
2020-01-01YesReturned to Compliance
1005MCL
Measured: 0.0230 MG/L (EPA limit: 0.010 mg/L)
2019-10-01YesReturned to Compliance
1005MCL
Measured: 0.0230 MG/L (EPA limit: 0.010 mg/L)
2019-07-01YesReturned to Compliance
1005MCL
Measured: 0.0150 MG/L (EPA limit: 0.010 mg/L)
2019-04-01YesReturned to Compliance
3014MR2016-09-15 MajorReturned to Compliance
7000Other2016-07-01Returned to Compliance
7500Other2013-06-12Returned to Compliance
0700TT2013-04-24YesReturned to Compliance
7500Other2011-12-25Returned to Compliance
7500Other2011-09-26Returned to Compliance
7500Other2011-09-18Returned to Compliance
7000Other2007-10-01Returned to Compliance
7000Other2006-07-01Returned to Compliance
7500Other2006-06-15Returned to Compliance
7500Other2005-09-22Returned to Compliance

Understanding This Water System's Record

Emerald Lake is a community water system water system that draws from groundwater sources and serves a population of 1,300 in Hillsboro, New Hampshire. This page shows its complete compliance history as reported to the EPA's Safe Drinking Water Information System (SDWIS), the federal database that tracks every public water system in the United States.

What Do These Violations Mean?

Health-based violations mean the system exceeded an EPA maximum contaminant level (MCL) or failed to provide required treatment. These indicate potential health risks from contaminants like lead, arsenic, bacteria, nitrates, or disinfection byproducts. Non-health-based violations involve monitoring, reporting, or procedural requirements — the system missed a testing deadline or failed to notify customers, but contaminant levels were not necessarily unsafe.

What Should You Do?

Your water utility is required to publish an annual Consumer Confidence Report (CCR) that details test results and any violations. If your system has active health-based violations, consider a certified water filter rated for the specific contaminants involved. The contaminant guides on this site explain health risks and filter options for common pollutants. For the most current results, contact your water utility directly — EPA data can lag weeks or months behind real-time testing.