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WaterQualityWatch -- Continuous Real-Time Water Quality of Surface Water in the United States
Real-Time Nitrate, in mg/L as N
* 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.