Resources for Households

When to Test Your Water

The Maine CDC recommends that residents with private wells test their water:

  • Every year for coliform bacteria, E. coli, nitrates, and nitrites.
  • Every 3-5 years for arsenic, chloride, copper, fluoride, hardness, iron, lead, magnesium, manganese, pH, radon, sodium, and uranium.

How to Test Your Well Water

More Information about Metals, Testing, and Financial Support:

Worth Watching:

EPA Standards for Drinking Water Contaminants

ContaminantSymbolEPA Maximum Contaminant Level*Standard TypeCommon Sources of Contaminant in Drinking Water
AntimonySb6 ppbPrimaryDischarge from various industries
ArsenicAs10 ppbPrimaryErosion of natural deposits and runoff from orchards
BariumBa2000 ppbPrimaryErosion of natural deposits and industrial discharge
BerylliumBe4 ppbPrimaryDischarge from various industries
CadmiumCd5 ppbPrimaryErosion of natural deposits, industrial discharge, and erosion of galvanized pipes
ChromiumCr100 ppbPrimaryErosion of natural deposits and industrial discharge
CopperCu1300 ppbSecondaryErosion of natural deposits and corrosion of household plumbing systems
IronFe300 ppbSecondaryErosion of natural deposits
LeadPb15 ppbPrimaryErosion of natural deposits and corrosion of household plumbing systems
ManganeseMn300 ppb
100 ppb if infant drinks water
(Minnesota recommendation)
Health Advisory LevelErosion of natural deposits and industrial discharge
NickelNi100 ppbaccording to ATSDRErosion of natural deposits and industrial discharge
SeleniumSe50 ppbPrimaryErosion of natural deposits and industrial discharge
ThalliumTl2 ppbPrimaryIndustrial discharge
UraniumU30 ppbPrimaryErosion of natural deposits
*National Primary Drinking Water Regulations (NPDWRs), primary standards, are legally enforceable standards that apply to public water systems. National Secondary Drinking Water Regulations (NSDWRs), secondary standards, are non-enforceable guidelines regulating contaminants that may cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effects (such as taste, odor, color) in drinking water.

PFAS in Drinking Water:

For those with questions about PFAS in drinking water, you may find helpful information at the following links

Recently, a homeowner in our Maine PFAS project received help from the Maine State Housing Authority’s well water abatement program to install a water filtration system!

Maine State Housing Authority Well Water Abatement Program

Are you a New Hampshire resident? New Hampshire supports PFAS testing and well remediation.

NH PFAS Response Program