Make Waves in 2026: Ace the Small Water System Operator Certification Exam!

Nitrate in water mostly comes from nitrogen compounds entering water supplies through human and agricultural activity, and from the natural breakdown of organic material in soils. The most common sources are fertilizers used in farming (synthetic or manure-based), waste from septic systems and sewage, and the decomposition of organic matter in soil and waste piles. These inputs leach or run off into groundwater and surface water and are converted to nitrate by soil microbes. Chlorine is a disinfectant and does not create nitrate, and heavy metals are a different class of contaminants related to industrial processes or corrosion. Natural rock minerals may contain trace nitrates, but they typically contribute far less to nitrate levels than the listed sources.