Operator terms · Water
What is a maximum contaminant level goal (MCLG)?
A maximum contaminant level goal, or MCLG, is the level of a contaminant in drinking water below which there is no known health risk, set as a health goal with a safety margin. It is a non-enforceable target. The enforceable limit is the MCL, set as close to the MCLG as is feasible.
Last reviewed 2026-08-03
Goal versus limit
The MCLG is a pure health target with a safety margin and is not enforced. The MCL is the enforceable legal limit, set as close to the goal as treatment can practically reach.
Why both exist
The goal says what would be ideal for health; the limit says what a system must actually meet. Together they show the gap between ideal and achievable.
Common questions
- Is an MCLG enforceable?
- No. It is a health goal. The enforceable limit is the MCL.
- How do MCLG and MCL relate?
- The MCL is set as close to the MCLG as is feasible.
- What does MCLG stand for?
- Maximum contaminant level goal.