WaterQualityWatch -- Continuous Real-Time Water Quality of Surface Water in the United States

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Real-Time Nitrate, in mg/L as N

Map of , showing which states provide real-time computed water-quality data
03338780 03339000 05536356 03353200 03275500 03374100 05515500 03378500 03346500 03353415 03353420 05524500 05517500 05518000 Explanation

* Site operated on a seasonal basis or currently is not operating.
No values are available for the last 6 hours.

The nitrate measurement is actually nitrate plus nitrite. Nitrite absorbs strongly at wavelengths similar to nitrate, and is not explicitly accounted for in the nitrate calculations by the sensors. For practical purposes, the concentration of nitrite is usually negligible in surface waters and has little effect on reported nitrate concentrations.

The "Real-time" map tracks short-term changes (over several hours) of water quality. Although the general appearance of the map changes very little from one hour to the next, individual sites may change rapidly in response to major rain events or to reservoir releases. The data used to produce this map are provisional.